Communication system and method for addressing multiple capacity wireless trunk

The present invention relates to a method and a system for providing a communication service.

Local telephone exchange systems, such as private branch exchanges (PBXs) and key type systems, have been in place for years as an alternative to public telephone services or as connected to public telephone services. Has been used in and other facilities. In a PBX or simple exchange system, users could make calls within their own system without accessing public telephone services. If there is a lot of telephone traffic in your own system, you can get great economic benefits by using such a system.

On the other hand, when a person using a PBX or a simple exchange system needs to call a person who is not connected to the above system, such an external call is generally a PBX or a simple exchange system controller. Must be routed from to to the public telephone company via the terrestrial line. To enable these two functions (ie, support for calls within your own system and support for external calls), you can manually route telephone calls when connecting to a PBX or simple exchange system. A dedicated telephone that can be used has been developed. For example, it is possible to provide a desktop telephone provided with buttons corresponding to different telephone lines. By pressing the appropriate button, the user selects between a private call call or another designated line for a call over a payphone network.

Some other PBXs and simple exchange systems automate the routing of calls over selected lines. For example, the user can choose whether the call is in their own system or over a payphone network by the first digit dialed, and the PBX or simple exchange system has that first digit. And route the call to the correct destination using the appropriate transmission means.

<p><patcit num="1"><text>U.S. Pat. No. 5,629,956.</text></patcit><patcit num="2"><text>U.S. Pat. No. 5,610,940.</text></patcit><patcit num="3"><text>U.S. Pat. No. 5,548,253.</text></patcit><patcit num="4"><text>U.S. Pat. No. 5,396,515.</text></patcit><patcit num="5"><text>U.S. Pat. No. 5,499,265.</text></patcit><patcit num="6"><text>U.S. Pat. No. 5,455,822.</text></patcit></p>

<p><nplcit num="1"><text>"Mobile Switching Center (MSC) to Base Station Subsystem (BSS) Interface; Layer 3 Specification", GSM Recommendation 08.08.</text></nplcit></p>

<p> PBXs and simple exchange systems are highly useful in that they economically cover private branch telephone systems, while long-distance users who use PBXs and simple exchange systems are connected to the PBX. It is necessary to rely on a local exchange carrier (LEC) that has a terrestrial communication line. LEC connects the call to a long-haul carrier. Long-distance calling services are very costly, especially when long-distance calls are heavily used, because users have to pay long-distance calling charges to both regional exchange carriers and long-distance carriers. It can be a thing.</p><p> In addition to the high cost of using long-distance services, another potential drawback of existing PBXs and simple exchange systems is that they are difficult or expensive to deploy in remote areas. .. For example, if long-distance services or other public network services are required, the deployment of PBXs and simple exchange systems is generally limited to areas where ground communication lines are installed. By doing so, it becomes possible to connect to a regional exchange carrier for connecting to a remote service provider in a PBX or a simple exchange system. If there is no terrestrial communication line at the desired deployment location, connecting to the terrestrial communication line for long-distance access using a PBX or a simple exchange system would be costly. Also, traditional PBXs and simple exchange systems can generally be less mobile when they require terrestrial lines and interfaces for long-distance access and other types of public network services. Can not.</p><p> There is a need for a communication system that has the functions of a PBX or a simple exchange telephone system that manages calls in the local area, and that can access long-distance services or other network services at low cost and with high reliability. A versatile mechanism is also needed to enable PBXs and simple exchange systems to achieve access to network resources and long-distance service areas at a relatively low cost. There is also a need for communication systems that use robust and flexible communication protocols to provide long-distance service areas and other network services to local users of PBXs, simple exchange systems or other types of local area networks.</p>

<p> The present invention provides, in one embodiment, a communication system having a wireless trunk that connects a plurality of telephone lines to a cellular (mobile phone) network via a wireless communication link. In one embodiment of the invention, a central telephone exchange or customer premises equipment (CPE), such as a private branch exchange or simple exchange system, is a wireless access communication device via one or more trunks. Connected to. The wireless access communication device provides the CPE with one or more wireless communication channels to the cellular network. Calls are selectively connected by the CPE and sent to the network over the terrestrial line or to a wireless access communication device that bypasses the terrestrial line. Within a base station capacity and traffic volume tolerance, multiple wireless access communication devices within a geographic area can communicate with a single base station in a cellular network.</p><p> Another aspect of the invention provides a wireless access communication device having a plurality of trunk interfaces connected to a CPE and a wireless transceiver that establishes one or more wireless communication links to a cellular network. Each trunk interface is connected to a line card with a vocoder and subscriber interface. The controller interfaces the line card with the wireless transceiver and assists in data conversion from a format suitable for wireless transmission to a format suitable for CPE trunk transmission, or vice versa. Data communicated between the wireless access communication device and the network is encrypted by the wireless access communication device and is separately transcoded by the mobile exchange center or between the mobile exchange center and the base station subsystem. Decrypted by the device.</p><p> In another aspect of the invention, the wireless access communication device registers each of the CPE trunks to which it connects when each CPE trunk is connected as if it were a subscriber to the network. Therefore, each CPE trunk may be addressed by a unique subscriber identification code. The wireless access communication device preferably utilizes various modes of GSM signaling to send information to the network, and the wireless access communication device can transparently communicate with the network based on GSM.</p><p> In yet another aspect of the invention, the wireless access communication device periodically re-registers each of its CPE trunks. The base station receives and monitors the re-registration signal from the wireless access communication device, and outputs an alarm message to the network if there is no re-registration signal within a predetermined time. The wireless access communication device is given a unique device identification code, which allows the base station to correlate different wireless communication links to a single wireless access communication device.</p><p> In yet another aspect of the invention, each trunk interface of the wireless access communication device is individually authenticated to derive a unique encryption key required for data encryption and decryption. The user key is stored in each trunk interface and in the central register of the network. In the authentication procedure, authentication parameters (eg, random numbers) are transferred to the trunk interface, which generates a signed response and an encryption key based on the stored user key. The network will generate a matching signed response and encryption key at one end. The wireless access communication device returns a signed response to the network, which is verified before further communication is allowed.</p><p> In yet another aspect of the invention, dialed digits (such as DTMF tones) are transmitted over a communication path that includes at least one radio communication link. In the call setup, the dialed digit is transmitted from the wireless access communication device to the base station as a signaling message. While the call is active, dialed digits are transmitted from the wireless access communication device to the network using GSM DTAP messages indicating the start and stop of each digit. DTAP messages are transparently relayed to the base station subsystem.</p><p> In a preferred embodiment of the invention, the wireless access communication device is a communication protocol utilizing various aspects of frequency division multiple access (FDMA), time division multiple access (TDMA), and / or code division multiple access (CDMA). By operating according to, a plurality of communication channels are assigned to the wireless access communication device on demand. In a preferred embodiment, communication between the wireless access communication device and the base station of the cellular network is carried out by a plurality of wireless full-duplex communication channels, one channel is assigned to each CPE trunk, and the base station transmits. Is performed in a time slot of a certain frequency band, and user station transmission (including those from a wireless access communication device) is performed in a time slot of a different frequency band. In such an embodiment, the user station time slot may be time offset from the base station time slot, and the radio transmission may be performed utilizing spectral diffusion techniques.</p>

<figref num="1">The figure which shows the architecture of the whole system in the preferable embodiment of this invention.</figref><figref num="2">The block diagram which shows the basic architecture of the wireless access communication apparatus in a preferable embodiment of this invention.</figref><figref num="3">The figure which shows the software architecture of the wireless access communication apparatus shown in FIG.</figref><figref num="4">A block diagram showing the basic architecture of a base station.</figref><figref num="5">The figure which shows the software structure of the base station shown in FIG.</figref><figref num="6">FIG. 3 is a block diagram showing address designation of a plurality of trunks connected to a wireless access communication device according to a preferred embodiment of the present invention.</figref><figref num="7">The figure which shows the structure of the interface signal system between a base station and a base station controller.</figref><figref num="8">Schematic showing the architecture of the system protocol.</figref><figref num="9">The figure which shows the division of the bearer path function between the components of a radio access communication apparatus (CPRU), a base station and a base station controller in the communication system of a preferable embodiment.</figref><figref num="10">The figure which shows the interface between different components in the system of a preferable embodiment.</figref><figref num="11">Explanatory drawing which shows a plurality of wireless access communication devices provided in different location areas and connected to a single base station controller.</figref><figref num="12">A call flow diagram showing the network level registration procedure.</figref><figref num="13">A call flow diagram showing the network level deregistration (DE-registration) procedure.</figref><figref num="14">A call flow diagram showing dial tone, digit transmission and digit analysis in a communication system with a PBX.</figref><figref num="15">A call flow diagram showing dial tone, digit transmission and digit analysis in a communication system including a simple exchange system (KTS).</figref><figref num="16">A call flow diagram showing dial tone, digit transmission, and digit analysis in a communication system with another type of PBX.</figref><figref num="17">Call flow diagram showing dial tone, digit transmission and digit analysis in a communication system including another type of KTS</figref><figref num="18">A call flow diagram showing a successful outgoing call setup when the PSTN does not interconnect.</figref><figref num="19">A call flow diagram showing the successful setup of outgoing calls when the PSTN interconnects.</figref><figref num="20">A call flow diagram showing a scenario that includes an incoming call during a call.</figref><figref num="21">A call flow diagram showing a scenario involving a three-way call.</figref><figref num="22">Call flow diagram showing DTMF tone transmission.</figref><figref num="23">A frequency distribution diagram showing frequency spectrum allocation according to an exemplary embodiment of the present invention.</figref><figref num="24">A frequency distribution diagram showing frequency spectrum allocation according to an exemplary embodiment of the present invention.</figref><figref num="25">The figure which shows the timing chart of the wireless communication protocol used in the communication system shown in FIG.</figref><figref num="26">The figure which shows the timing chart of another wireless communication protocol used in the communication system shown in FIG.</figref><figref num="27">The figure which shows the authentication process.</figref><figref num="28">A call flow diagram showing network-level registration.</figref><figref num="29">A call flow diagram showing alarm reporting processing.</figref>

Further embodiments, improvements, modifications and functional enhancements of the present invention are also described below.

FIG. 1 shows the overall system architecture of the communication system 101 according to a preferred embodiment of the present invention. In the system architecture shown in FIG. 1, a plurality of telephone station devices 102 are connected to the central telephone exchange 105. It is understood that the telephone station device 102 herein may be a telephone or any other device capable of communicating via a modem, fax, or completed call connection. It is a place to go. In the present specification, the central telephone exchange 105 is referred to as a customer premises device or CPE, but the CPE 105 may be, for example, a private branch exchange (PBX) or a simple exchange system (key system). Various configurations of these PBXs and simple exchange systems are well known in the art.

In the preferred embodiment shown in FIG. 1, the CPE 105 is referred to as a public switched telephone network (PSTN) 125 and a wireless access communication device 106 (referred to herein and in the drawings as a "customer premises radio device" or "CPRU". May be connected to both. As will be described in detail later, in a preferred embodiment, the call is selectively connected to either the PSTN 125 or the wireless access communication device 106 depending on the type of the call. The wireless access communication device 106 communicates with the base station 109 via a wireless trunk 108 (consisting of a plurality of wireless communication links). The base station 109 is connected to the base station controller 112 together with other geographically adjacent or adjacent base stations 109. The base station controller 112 is connected to a transcoding device 115, which is a mobile switching center. center: MSC) Connected to 116. If desired, the base station controller 112 may be directly connected to the mobile exchange center 116 without interposing the transcoding device 115. The mobile exchange center 116 is connected to the PSTN125.

In addition to being connected to the transcoding device 115 (and optionally to the MSC116), the base station controller 112 is also connected to the operations and maintenance center (OMC) 120, which is the operations and maintenance center. 120 is connected to operations support system (OSS) 122. As shown in FIG. 1, the mobile exchange center 116 is connected to the home location register and authentication center (HLR / AuC) 123 and the operation support system 122. The base station 109 may also be connected to the regional management terminal 121.

As will be described later, the present invention in one aspect provides signal transmission techniques and protocols for facilitating communication in systems with wireless trunks. Signaling information is transferred via one or more of the various interfaces of communication system 101 so that communication between CPE 105 and PSTN 125 can be performed utilizing the functionality of wireless access communication device 106. In a preferred embodiment, the communication system utilizes a "hybrid" protocol incorporating various aspects of the IS-661 communication protocol (or a modified version of the IS-661 protocol) and the GSM communication protocol. A detailed description of preferred signal transmission techniques and protocols will be given after some of the basic components of a preferred system have been described along with their operation.

As described below, the invention in one aspect transfers dialed digits (eg, such as DTMF tones) over a communication path that includes at least one radio link. During call setup, the dialed digit is sent from the wireless access communication device 106 to base station 109 as a signaling message. While the call is active, dialed digits are sent from the wireless access communicator 106 to the network using GSM DTAP messages indicating the beginning and end of each digit. The DTAP message is transparently relayed to the mobile exchange center 116 via the base station 106 and the base station controller 112. A detailed description of this digit transmission will be given after some of the configuration and operation of the basic components of a preferred system have been described.

Further, as will be described later, the present invention in one aspect provides an authentication and security technique in a wireless communication system such as the communication system shown in FIG. Preferably, the wireless access communication device 106 can support a plurality of trunk or user interface connections connected to the CPE 105, in which case authentication is performed individually for each trunk or user interface connection. In some embodiments, the wireless access communication device 106 is treated by the network as a collection of individual subscribers. Each trunk or user interface connection supported by the wireless access communication device 106 derives its own encryption key based on the authentication parameters received from the network. Therefore, the wireless access communication device 106 is a plurality of encrypted bearers routed over a network, which are bearer routes each having a unique unique encryption pattern. paths) is provided. A detailed description of preferred authentication and security techniques will be given after some of the basic components of a preferred system have been described along with their operation.

In the preferred communication system 101 shown in FIG. 1, the call may be connected directly from the telephone station device 102 via the PSTN 125 (ie, via a land communication line connection) or the wireless access communication device 106. It may be connected to the PSTN 125 via a wireless trunk 108 in use. When making a call from one of the telephone station devices 102, the call may be routed directly to the PSTN 125 or to the wireless access communication device 106. The routing of such calls may be based on manual selection or automatically based on dialed numbers, the details of which will be described later. In a preferred embodiment, short-range phone calls are routed directly to the PSTN 125, while long-range phone calls are routed through the wireless access communication device 106.

The operation of the system shown in Figure 1 depends in part on the characteristics of the CPE. As mentioned above, the CPE105 is, for example, a PBX or a simple exchange system (key-type). system) may be included. In an embodiment where the CPE 105 is equipped with a PBX, the PBX preferably makes an outgoing call from the telephone station device 102, depending on either the telephone number dialed by the user or the access digit, wireless access communication. Route to either device 106 or PSTN125. For example, the user first dials a given digit (eg, "8") to access the wireless access communication device 106, and another digit (eg, "e.g.") to make direct LEC access to the PSTN125. Dial "9") first. In this way, for example, the user can access the wireless access communication device 106 to make a long-distance outgoing telephone call, or access the PSTN125 to make another type of outgoing call. Become. Alternatively, some PBXs may be configured to analyze dialed numbers to route long-range and short-range calls. By using this function, the PBX can be configured to route long-distance calls via the wireless access communication device 106, but short-range and emergency calls via PSTN125.

In the embodiment in which the CPE 105 is equipped with a simple exchange system, the user may manually select a line (a line to the wireless access communication device 106 or a line to the PSTN 125) by pressing a button on the telephone body. .. For example, the user would select wireless access communication device 106 as the call processor for long-distance outgoing calls and PSTN125 for other outgoing calls. Some simple exchange systems, like some PBXs, analyze the dialed number and make the call according to the first digit of the call and / or the number of digits dialed. It may be configured to route to any of the PSTN125. In this way, a simple exchange system can be configured so that, for example, long-distance calls can be routed via the wireless access communication device 106, and short-range or emergency calls can be routed through the PSTN125.

In another embodiment, the system may be configured to potentially simplify the architecture, albeit with less flexibility. For example, ensure that all incoming calls are routed directly from PSTN125 to CPE105, while all short-range outgoing calls (whether voice or data), all long-range data outgoing calls, and disability. The system may be configured so that all TTY calls for a person are routed directly through the PSTN125. In such an embodiment, the wireless access communication device 106 will generally have a long-distance voice communication transmission function.

The CPE 105 is connected to the wireless access communication device 106 via the CPE trunk interface 104. The CPE trunk interface 104 comprises a plurality of CPE trunks, each of which may include, for example, a loop start trunk or a ground start trunk known to those of skill in the art. As is well known to those skilled in the art, both loop start trunks and ground start trunks can be supported by the same regional exchange facility (ie, the same PBX or KTS).

In an embodiment in which the CPE 105 is equipped with a PBX, the PBX preferably has predetermined operating characteristics. That is, the PBX supports loop-start trunks and / or ground-start trunks on the CPE trunk interface 104 between the PBX and the wireless access communication device 106, as well as loop-start trunks or ground-starts. It is also desirable to support the DTMF address signaling scheme on the trunk. This PBX can be configured to route calls through either the PSTN125 or the wireless access communication device 106 as described above, so which trunks connect to the PSTN125 and which trunks are wireless. It is desirable to have a function to identify whether it is connected to the access communication device 106. The PBX specifies the order of the trunks to try when an outgoing call is made, and instead of the wireless access communication device 106 when there is a problem accessing the wireless system from the wireless access communication device 106. It is desirable to have the ability to reroute long-range outgoing calls via PSTN125.

On the other hand, in an embodiment in which the CPE 105 is equipped with a key telephone system (KTS), the KTS preferably has predetermined operating characteristics. That is, in addition to being configured to support loop-start trunks and / or ground-start trunks on the CPE trunk interface 104 between the KTS and the wireless access communication device 106, the KTS is loop-start. Alternatively, it also supports the DTMF address signaling scheme on the ground-start trunk and preferably has the ability to route calls via either the PSTN125 or the wireless access communication device 106 as described above. Also, although this is not always required, supplementary call support The KTS may have a route selection function (that is, a function of identifying the trunk groups connected to the wireless access communication device 106 and the PSTN125 and specifying the order of the trunk groups to be tried on the KTS). If the KTS is equipped with a route selection function in this way, a long-distance outgoing call will be made via PSTN125 instead of the wireless access communication device 106 in the event of a problem in accessing the wireless system from the wireless access communication device 106. Must have the ability to reroute.

The wireless access communication device 106 acts as a gateway for a wireless trunk that accesses the CPE 105 via a wireless system, and connects individual CPE trunks with a wireless communication link so that calls from the CPE 105 can be completed over the wireless network. Correlate. FIG. 6 shows an embodiment of a wireless access communication device 605 connected to the CPE 105 (see FIG. 1) via a plurality of (four in the illustrated example) CPE trunks 602. The wireless access communication device 605 is connected to a wireless network, in particular to a base station (not shown in FIG. 6), via a plurality of wireless communication links (or "pipes") 609. The wireless access communication device 605 establishes a wireless communication link 609 and correlates it with the CPE trunk 602, whereby communication relating to the specific CPE trunk 602 is performed via the assigned wireless communication link 609. become. A user connected to the CPE 105 can gain access to the wireless access communication device 605 (and thus to the wireless network) by connecting to any CPE trunk 602 via the CPE 105. In this way, a potentially large number of users connected to the CPE 105 have the ability to complete calls to the wireless network, and the number of users who can make simultaneous calls is the available CPE Trunk 602 ( As a result, it is equal to the number of wireless communication links 609).

As described above, the wireless access communication device 106 operates as a gateway of the CPE 105 that accesses the wireless network, and preferably performs various functions. In a preferred embodiment, the wireless access communication device 106 performs off-hook detection for outgoing calls and supports the delivery of dial tones to the CPE 105 (and thus to the calling telephone station device 102). The wireless access communication device 106 also initiates acquisition of radio communication channels (eg, radio time slots if the radio network is a TDMA and / or TDD system) and initiates a call control procedure. While the call is established, the wireless access communication device 106 detects the dialed address digit (ie, DTMF tone) and transfers the detected digit to the network using the call control signaling scheme. The wireless access communication device 106 receives from the base station 109 and makes a normal call or makes an emergency call according to the dial end sign indicating the type of call (based on the digit analysis performed at the base station 109). Determine if to make a call. The wireless access device 106 also detects an off-hook transition from the CPE 105, and in response to this off-hook transition, starts a call release procedure for the network. When the call is completed, the radio communication device 106 provides transparent control for the land communication line related to the disconnection procedure for the end-of-call process initiated by the CPE 105. As part of this functionality, the wireless access device 106 implements release guard times supported by conventional wireless systems.

In addition to the functions described above, the wireless access communication device 106 also supports DTMF digit signaling while the call is active. As part of this function, the wireless access communication device 106 detects the DTMF tone from the CPE 105 while the call is active and relays the digit to the network using the DTAP signaling scheme. Also, during the call, the wireless access communication device 106 may appear to transparently transfer the call progress sound received from the network to the CPE 105 via the bearer path. Whenever a call progress DTAP signal scheme is received from the network, the wireless access communication device 106 converts the call progress DTAP signal into a call progress sound to the CPE 105. The wireless access communication device 106 generates a reorder sound to the CPE 105 when necessary to notify the CPE 106 about the congestion of the wireless network or the permanent signal timer expiry conditions. May be good.

Further, it is desirable that the wireless access communication device 106 can perform a large number of functions related to bearer processing. For example, as a preferred embodiment, the wireless access communication device 106 performs vocoder processing (electrical voice analysis synthesis: vocoding) of voice communication. To elaborate on this, vocoder processing is the coding and / or compression of speech for in the network and the decoding and / or decompression of speech in the opposite direction (ie, for sending to CPE106). And include. Further, as the wireless access communication device 106, forward error correction (FEC) and encryption and decryption of bearer voice (the wireless access communication device 106 and the transcoding device 115 are peer-to-encryption encryption). It is desirable to also perform the echo cancel function (which is a peer endpoint). For encryption and decryption, the wireless access communication device 106 encrypts the bearer data prior to wireless transmission (ie, transmission via the wireless trunk 108) and decrypts the bearer data received from the network. The echo cancel function is a wireless access communication device to suppress the echo that may be potentially generated toward the wireless network, for example, when there is a 2-wire and 4-wire hybrid structure at the interface with the CPE105. Supported by 106.

In a preferred embodiment, the wireless access communication device 106 related to the wireless system provides management and security functions such as a call registration function, a deregistration function, a user authentication function, a bearer information encryption function, and a network management function. Supports. In addition to providing a means for voice outgoing calls, the wireless access communication device 106 provides emergency outgoing calls (ie, "911") and end-to-end DTMF signals while the call is active. It is desirable to support the method.

The detailed configuration of the preferred wireless access communication device 201 is shown in FIG. 2, and the details of the preferred software configuration of the wireless access communication device 201 are shown in FIG. As shown in FIG. 2, the wireless access communication device 201 connects a plurality of CPE 105s (see FIG. 1) to the wireless access communication device 201 via a trunk interface (for example, the trunk interface 104 shown in FIG. 1). It has a subscriber port 203. Each subscriber port 203 supports one call connection via the wireless access communication device 201, and may be configured by, for example, an RJ-11 type interface. Although FIG. 2 shows that there are a total of four subscriber ports 203, the number of these subscriber ports 203 varies depending on the specific use of the wireless access communication device 201 or its environment. For example, the wireless access communication device 201 may include only one subscriber port 203, or may include the number of wireless communication channels that the wireless communication device 201 is generally accessible and available. It may have any number of subscriber ports 203 limited only by practical considerations. Further, the subscriber port 203 may be any interface, but the above-mentioned RJ-11 type interface is only an example of such an interface.

Each subscriber port 203 is connected to an individual line interface device or line card unit 205. Therefore, the wireless access communication device 201 includes four line card units 205, one for each subscriber port 203. The line card unit 205 provides a physical subscriber line interface from the CPE 105 to the wireless access communication device 201, and also provides digitization and data compression functions.

Although FIG. 2 shows the details of one of the plurality of line card units 205, the remaining line card units 205 are similarly configured. The line card unit 205 includes a subscriber interface 207 connected to any one of the subscriber ports 203. This subscriber interface 207 is a subscriber line interface. Equipped with circuit: SLIC) 217, it provides conventionally known loop interface features including battery power supply, overload protection, monitoring, 2-wire and 4-wire hybrids, and more. It is desirable that the line card unit 205 supports both loop start and ground start signal systems. For example, a manual toggle switch or DIP switch (not shown) provided in the wireless access communication device 201 may be used to select between the loop start signal method and the ground start signal method, and each line card may be used. Part 205 may be individually configured to interface with a loop start or ground start trunk. The subscriber interface 207 is also a standard CODEC, or as an alternative, a subscriber line audio processing. It is equipped with circuit: SLAC) 215, which enables analog-to-digital conversion and digital conversion between the line card unit 205 and the user station connected to the subscriber port 203 (for example, the telephone station device 102 shown in FIG. 1). Perform analog conversion. The CODEC to SLAC215 have a standard μ-method pulse code modulation (PCM) interface. Subscriber interface 207 also includes a ring generator 216 that produces a ring tone.

A digitized data stream is output from the CODEC or SLAC 215 and is supplied to the vocoder 206 via one or more signal lines 214, which compresses the digital data stream into a compressed data signal. The vocoder 206, like the relatively fast digital signal processor 211 (eg, operating at 20 million instructions per second or any other suitable speed), and the fast static random access memory (SRAM) 212 and EPROM 213. It consists of a support module of. The vocoder 206 preferably addresses a situation in which, for example, the wireless access communication device 201 detects a data frame containing an error or a data frame containing an error that cannot be corrected by forward error correction (FEC). An interpolation function for deriving a pattern is provided as part of its own decoding function. It is also desirable that the vocoder 206's decryption feature include a mute feature that silences the output to the CPE 105 if beneficial, which is beneficial, for example, when exchanging control traffic. is there. The vocoder 206 outputs a compressed data signal at a rate of, for example, 8 Kbp, and this signal is supplied to a control line card assembly (LCA) 226 provided in the control unit 220. As a result, the control unit 220 receives four compressed data signals, one for each line card unit 205.

Each line card section 205 has a subscriber interface module. module: SIM) 208 is also provided. The general function of SIM208 is to provide system security and to store subscriber-specific information, including information such as subscriber authentication information and subscriber-specific data. In a preferred embodiment, the SIM function is replicated for each CPE trunk supported by wireless access communication device 201 so that each CPE trunk may be considered as a different subscriber by the network. .. This duplication will be described with reference to FIG. FIG. 6 shows that multiple CPE trunks 602 are connected to the wireless access communication device 605 (each CPE trunk 602 is connected to the subscriber port 203 shown in the detailed diagram of FIG. 2). .. A separate SIM 606 is associated with each CPE trunk 602. Therefore, if there are four CPE trunks 602, the wireless access communication device 605 has four SIM 606s. This wireless access communication device 605 is a plurality of wireless interface devices 607, one for each CPE trunk 602, for transferring data and other information to a wireless transceiver (not shown) that handles the physical wireless communication link 609. Is further equipped.

In general, each subscriber in a communication system requires unique identification parameters and possibly different system parameters. As long as multiple CPE trunks (corresponding to multiple subscriber ports 203 shown in Figure 2) are considered by the system as individual and unique subscribers, each CPE trunk will have a unique identifier and preferably unique authentication parameters and others. Associated with the system parameters of, these are implemented at least partially utilizing the separate SIM 208 used in each line card 205.

The functionality of SIM208 may be implemented as one or more non-removable SIM chips within the hardware architecture of the wireless access communication device. The SIM 208 stores subscriber information such as a subscriber identifier in a non-volatile memory (for example, ROM or non-volatile RAM). In a preferred embodiment, an international mobile subscriber identifier (IMSI) number is used as the subscriber identifier. In addition to storing the subscriber identifier as described above, the SIM208 performs authentication procedures such as the "A3" and / or "A8" authentication procedures conventionally used in certain GSM applications. It is designed to do. This certification will be described in detail later.

The present invention in certain embodiments relates to the security features of a preferred communication system 101, including a wireless access communication device 106. Such security features include, for example, authentication and encryption.

Since the wireless access communication device 106 uses the wireless resources of the short-range mobile cellular system, the identity information of the wireless access communication device 106 is illegal in the same way as another person attempts to illegally use a mobile phone (handset). It is conceivable that you will try to use it for. For example, mobile phones may be cloned in many analog mobile phone networks, resulting in a large loss of profit due to such unauthorized use of the phone.

For this reason, in the preferred communication system 101, an authentication procedure is used both to prevent unauthorized use of network resources and to protect the wireless access communication device 106 (and other wireless entities) from spoofing. Is used. Authentication is performed for each user registration, and it is desirable to use the 1-in-N method as part of the normal call setup, that is, to authenticate once for every N calls. However, N is set appropriately according to the system.

Also, in a preferred embodiment, authentication requests and responses are to be forwarded between the MSC116 and the wireless access communication device 106 as part of the GSM mobility management (MM) protocol. It is also based on the GSM A3 / A8 certification mechanism. On the user side, the wireless access communication device 106 includes a standard GSM SIM function for each CPE trunk. In the wireless access communication device 106, the subscriber's identity information (that is, IMSI) and the subscriber key value (K) are stored in the GSM SIM function associated with the CPE trunk for each CPE trunk. .. On the network side, the MSC116 requires a set of credentials for the home location register (HLR) component of the HLR / AuC123. In a preferred embodiment, this set of authentication information comprises three authentication parameters referred to herein as triad authentication information. Of the HLR / AuC components of the HLR / AuC123, the HLR component transfers a set of credentials to the MSC116.

The triplet authentication information spans the generated random number (RAND), the signed response (SRES) used to authenticate the subscriber's SIM card, and the wireless link between the wireless access communication device 106 and the network. An encryption key (K) used to encrypt and decrypt information_c) And three. Subscriber key value K stored in both the AuC component of the HLR / AuC123 and the wireless access communication device 106_iIs used in either of two separate algorithms (commonly known in the art as A3 and A8), or in a combined A3 / A8 algorithm, thereby the encryption key K for the authentication procedure._cAnd the signed response SRES are generated. The AuC component of the HLR / AuC123 uses a random number generator to generate a random number RAND, and the generated random number RAND is supplied to the wireless access communication device 106 by the MSC116. The wireless access communication device 106 uses this random number RAND as the subscriber key value K._iGenerates a signed response SRES by inputting to the A3 algorithm together with the encryption key K by inputting to the A8 algorithm._cTo generate.

This signed response SRES is returned to the MSC116 and subsequently compared by the visitor location register (VLR) with the signed response value in the VLR. If the returned signed response SRES matches the signed response value in the VLR, the subscriber is authorized to register, make a call, and interact with other networks. On the other hand, if the returned signed response SRES does not match the signed response value in the VLR, the subscriber is prohibited from registering, calling and interacting with other networks. In such a case, base station 109 is notified by MSC116 that the authentication attempt has failed, and base station 109 terminates the call connection to the wireless access communication device 106 with a message of authentication failure. ..

Preferably, the AuC component of the HLR / AuC123 and the SIM component are the subscriber key value K._iIs the only part we know about the existence of and the A3 / A8 algorithm. The AuC component of HLR / AuC123 generates a new random number RAND for each authentication request, signed response SRES and encryption key K._cAnd, if necessary, transfer them to the AuC components of the HLR / AuC123 and the MSC116. MSC116 has a signed response SRES or encryption key K_cDoes not have to be involved in the actual derivation of.

FIG. 27 is a diagram illustrating an authentication procedure, which includes division of functions in a preferred embodiment of communication system 101. Random number RAND, signed response SRES and encryption key K, as shown in Figure 27._cThe triad credentials, including, are stored in the VLR of the MSC116 after being transferred at the request of the HLR / AuC123. The random number RAND is sent to the wireless access communication device 106, where the signed response SRES and the encryption key K_cSubscriber key value K to generate locally_iUsed with. The signed response SRES is returned to the MSC116 by the wireless access communication device 106 for comparison with the SRES stored in the VLR of the MSC116. Then the encryption key K_cIs used to encrypt transmissions over wireless communication channels.

Bearer encryption on the user side is performed by the wireless access communication device 106. Encryption of bearer information on the network side is preferably performed by transcoding device 115. Optionally, encryption of signaling messages (eg, control traffic) may be performed. A variety of suitable algorithms can be selected for bearer encryption. For example, the GSM A5 / 1 algorithm can be used for such purposes.

Encryption key K during the authentication process as part of call establishment_cThe encryption process may be set up using the cipher mode setting procedure in connection with the establishment of. Encryption key K_cMay be relayed from the MSC 116 to the base station controller 112, which in turn sends the encryption key K to the base station 109 using a signaling message through the N-interface 562._cTo relay. The base station 109 then uses an inband signaling scheme to provide the encryption key K._cIs relayed to the transcoding device 115 and replied.

Explaining again with reference to FIG. 2, the control unit 220 of the wireless access communication device 201 performs timing and control in substantially all aspects of the wireless access communication device 201. Control 220 includes, for example, a processor 225 consisting of a 16-bit RISC processor (such as a Siemens C165 or C163 processor) and associated support modules (ie, SRAM, flash memory, etc.). Access to the SIM 208 is initiated by the host processor 225 and controlled by the control line card assembly (LCA) in the control unit 220 to perform formatting. Processor 225 also coordinates the activities of many systems to move data between various modules.

The processor 225 is connected to the control LCA226, and the control LCA226 is connected to the vocoder from each of the line card units 205 as described above. The control LCA226 is also connected to a radio interface control line card assembly (RIFLCA). The control LCA226 provides an interface between the radio unit and the line card unit of the wireless access communication device 201. Control The LCA226 packages and formats the data and coordinates and controls the over-the-air (OTA) protocol. This maintains cooperation between up to four serial data streams (one from each line card section 205) and their respective wireless communication channels.

The wireless interface LCA227 is connected to the baseband processor 228. The baseband processor 228 may include a digital radio ASIC (DRA) 229. The baseband processor 228 is connected to the radio unit 240. The radio unit 240 preferably comprises a plurality of antennas 243 that can be selected by a selector 242 connected to the control LCA226. This provides signals from one or more antennas 243 to the radio transceiver 241 (or one radio transceiver for each antenna 243). In one embodiment, antenna diversity technology is used to select the best antenna (and / or wireless receiver) for each time frame in which the wireless access communication device 201 communicates.

The wireless access communication device 201 may be powered by either an external DC power source 250 or an onboard battery 251. The battery 251 can be used as a spare power source and is automatically used when the external power source 250 is disconnected or unavailable. The power unit 221 of the wireless access communication device 201 may include a local voltage regulator that supplies the required power to the logic unit and the radio unit, and a switching regulator that supplies any required loop battery voltage.

The wireless access communication device 201 may include an LED 231 or other visual display mechanism to indicate the status of the device to the observer. The types of status status displayed are, for example, whether the device is powered on, whether the device is functioning (ie, passed all self-tests), or whether the device is in service. (Ie, is it currently registered with the base station).

During operation, the compressed serial data is transferred between the plurality of line cards 205 under the control of the control LCA226. The control LCA226 formats the compressed serial data into a format suitable for the wireless interface LCA227. In addition, the control LCA226 performs arbitrary desired encryption and adds forward error correction information. The control LCA226 sends data to the wireless interface LCA227, and the wireless interface LCA227 sends the data to the baseband processor 228. The wireless interface LCA227 tracks channel and timing information and instructs baseband processor 228 to process the data according to channel and timing parameters. In a preferred embodiment, the baseband processor 228 formulates a continuous phase modulated spectral diffused signal, or other type of quadrature phase signal or related signal, as described, for example, with respect to the transmitters shown in Patent Documents 1-3. Includes transmitter to. At appropriate time intervals, the baseband processor 228 sends data to the wireless section 240, which converts the signal to the appropriate transmission frequency and transmits it wirelessly, as determined by the wireless interface LCA227. Perform any necessary filtering on the. The frequency band used by the wireless access communication device 106 is generally dominated by the overall communication system in which the system is deployed. For example, the frequency band may be within the PCS frequency band of 1930-1990 MHz, or any other suitable frequency band of one or more.

The incoming message signal is received by one or more antennas and sent to the radio transceiver 241 for down-conversion and / or filtering as needed. The down-converted and / or filtered data is then sent to baseband processor 228, which demodulates the received signal. In a preferred embodiment, the wireless access communication device 201 transmits and receives data using a spread spectrum format. In such an embodiment, the baseband processor 228 preferably comprises a spectral diffusion correlator. A variety of spectral diffusion correlators are known in the art, examples of which are embodiments described or described in Patent Documents 1, 2, 4 and 5.

The baseband processor 228 outputs a received signal strength indicator signal (RSSI), among other things, when the control LCA226 selects the best antenna 243 (and / or wireless receiver) to receive the incoming signal. used. After spectral diffusion correlation processing, the baseband processor 228 outputs a stream of data bits to the wireless interface LCA227, which wireless interface LCA227 is based on the wireless communication channel on which the data was received to the appropriate line card 205. Transfer data. The data is then processed by the line card 205 and sent to the CPE 105 via a particular subscriber port 203 connected to the line card 205.

FIG. 3 is a diagram of a preferred software structure for the wireless access communication device 201. As shown in FIG. 3, the software of the wireless access communication device 201 is functionally divided into two main components based on the physical interface supported by the wireless access communication device 201. These two main components are referred to as line management unit 350 and radio management unit 351.

The line management unit 350 generally handles CPE trunk management and communication between the wireless access communication device 201 and the CPE 105. In addition to this CPE trunk management and communication interface function, the line management unit 350 is in charge of the call signal system, DTMF recognition, and transfer of the collected DTMF digits to the radio management unit 351. The line management unit 350 includes a plurality of line drivers 303 and a plurality of SIM drivers 304, and one line driver 303 and one SIM driver 304 are provided for each CPE trunk supported by the wireless access communication device 201. Be done. One line driver 303 and one SIM driver 304 are combined to form one CPE line software component 302.

The radio management unit 351 handles the communication interface and link management to the base station 109 (see Fig. 1). In addition, the radio management unit 351 receives the DTMF digit from the CPE 105 (via the line management unit 350) and relays the DTMF digit to the base station 109 (eventually, as explained in detail above). (Sent to PSTN125). The radio management unit 351 also implements a radio communication protocol, including end-to-end communication with various network entities such as base station controller 112 and mobile exchange center 116 (see FIG. 1). An example of a radio communication protocol implemented by radio management unit 351 is, for example, the GSM direct application transfer part (DTAP) protocol, or the IS-661 radio described herein (O. -Notes ") Protocol. At the physical radio level, the radio management unit 351 of the radio access communication device 201 preferably implements the IS-661 protocol.

As further shown in FIG. 3, the radio management unit 351 includes a plurality of CPE line link objects 310, one for each CPE trunk (ie, subscriber port 203) supported by the radio access communication device 201. Each CPE line link object 310 provides signaling resources for a single CPE circuit or trunk and comprises several components that together form a signaling protocol stack. These components of the signaling protocol stack work together as an interface to the CPE line to use the radio resource capabilities and network resources needed to complete call management, mobility management, and voice calls. Provides the registration function required for.

Each CPE line link object 310 comprises a CPE line management unit 311 whose purpose is to interface with the CPE line software component 302 for a suitable CPE line or trunk. In a preferred embodiment, the CPE line management unit interfaces with the GSM call management unit 312 and the GSM call registration management unit 313, both of which interface with the GSM mobility management component 314. GSM mobility management component 314 interfaces with protocol adaptation (PAL) component 315, and protocol adaptation (PAL) component 315 interfaces with wireless (OTA) state machine 316. The OTA state machine 316 is generally responsible for managing the physical radio interface and communicates with the radio transmit / receive interface and slot management (RTRX) component 321.

During operation, the CPE line management unit 311 signals the GSM mobility management component 314 to initiate the connection establishment procedure, as described in detail later with reference to the call flow diagrams of FIGS. 13-22. To do. In addition, the CPE line management unit 311 sends a DTMF digit to the network, enables the voice path, generates a ring tone, generates a busy tone (when the PSTN does not interconnect), and sends it to the CPE 105. Controls the transmission of on-hook display signals. In addition, the CPE line management unit 311 manages the procedures for normal and emergency calls, as well as the end-of-call processing initiated by the CPE.

The GSM call management component 312, the GSM registration component 313, and the GSM move management component 314 provide some (stage) GSM functionality related to call management, registration, and move management, respectively. Protocol adaptive component 315 adapts the GSM signaling protocol to a radio protocol (eg, such as the IS-661 radio protocol), if necessary. The OTA state machine 316 implements the radio protocol and manages the physical radio interface as described above.

In addition to the plurality of CPE line link objects 310, the OTA management unit 351 further provides a programming interface to the hardware of the wireless access communication device 201 (including the hardware controlled by the line driver 303 and the SIM driver 304). , With hardware service component 320. OTA management unit 351 may include a power-on / reset initialization (POST) component 323 and debug port management unit 322, as well as a real-time operating system (RTOS) 330, which is a multitasking operating system. May be good. When the debug port management unit 322 is provided, the internal state of the software can be accessed from the outside and the software download is permitted.

In addition to the components described above, the OTA Management Unit 351 also includes an operations, administration and management (OAM) component 324. The OAM component operates at the application level and performs functions such as fault recognition, alarm generation and transmission, and fault detection and communication with line management 350 for call processing data required for alarms. .. The types of failures or failures monitored are, for example, hardware failures (such as power failure, wireless device failure, line card failure, etc.), software failure, communication failure, and service quality failure (eg, per time cycle). Unsuccessful call attempts, time slot exchange requests per time cycle, unsuccessful time slot exchanges per time cycle, number of lost calls per time cycle, channel quality displayed by bit error rate Etc.), and others may be included. Failure reporting may be coordinated so that a single failure that causes multiple failures due to dependencies between software, hardware, and telecommunications features is reported as a single failure.

In one embodiment, the function of the radio management unit 351 used to support the wireless access communication device 201 can be regarded as a subset or variant of the function used to support the mobile user application. For example, the mobility management interface used to support mobile users in traditional GSM systems. The interface: MMI) software component is replaced by the CPE line management unit 311 in the software architecture illustrated in Figure 3. Another difference regarding mobile user applications is that the logical instances of the signaling protocol stack (as opposed to having the signaling protocol stack as a single logical instance in the case of mobile user applications) have wireless access communication. Provided for each CPE line connected to device 201 and the SIM driver moved to accommodate multiple SIMs (or their logical equivalents), for example by providing multiple independent SIM drivers 304. It is to be transformed for the body user application. In addition, the ability to associate the hardware voice path from CPE105 with the base station communication link will be added. The signaling protocol is also modified to support digit analysis by base station 109 (see Figure 1), as detailed herein. The DSAT and DTA adapter software components traditionally used in certain mobile user applications are not required by the wireless access communication device 201 and are therefore not implemented.

Referring again to FIG. 1, the wireless access communication device 106 interfaces with the base station 109 of the wireless system, as described above, thereby allowing final access to the PSTN 125. A block diagram of the preferred base station 401 is illustrated in FIG. Base station 401 comprises a number of separate components connected to each other by a common global bus backplane. These components include a digital line card 404, a wireless (OTA) processor card 405, a power supply module 407, and a plurality of wireless cards 406, all of which reside on the electronic circuit module 420. The electronic circuit module 420 is connected to an I / O module 421 provided with a protection circuit 403 to prevent damage due to a short circuit or the like. Each wireless card 406 is connected to one of a plurality of antennas 403 via a protection circuit 403. The digital line card 404 is connected to the PSTN125 (via the base station controller 112 and MSC116) on the backhaul line 430 via protection circuit 403, or also other physical. It is connected to another base station 109 on a digital connection. If possible, base station 401 may be connected to local AC power line 425.

During operation, the wireless access communication device (indicated by reference number 412 in FIG. 4) sends and receives wireless messages to and from base station 401. In base station 401, a plurality of antennas 411 and wireless card 406 are used to achieve antenna diversity. Typically, one antenna 411 is selected to transmit or receive a radio signal at a given time. When using spread spectrum communication, the OTA processor card 405 is a spectrum spread correlator and other baseband processing circuit for correlating the spread spectrum signal received from the wireless access communication device 412 and converting it into data bits. Can be provided. OTA processor card 405 transfers data to digital line card 404, digital line card 404 formats the data and directs it to PSTN125, such as other intervening system components (such as base station controller 112 and MSC116). Send on the backhaul via digital). Similarly, the digital line card 404 receives data from the PSTN125 and transfers the data to the OTA processor card 405, which formats the data for the wireless protocol and selects the wireless card 406 and antenna. Formatted data is transmitted using 411.

The main functions of the wireless card 406 are to send and receive RF data packs, to perform packet data integrity services (eg cyclic redundancy check), and to support antenna diversity algorithms. The main function of the OTS processor card 405 is to move bearer data between the wireless card 406 and the digital line card 404. The OTA processor card 405 also executes operations, administration, management and provisioning (OAM &amp; P) requests from the digital line card 404 and provides signaling information (internal) to and from the digital line card 404. Communicates (using a base station message or "I-note") and communicates signal system information (using a radio signal system message or "O-note") with the wireless access communication device 412.

The main function of the digital line card 404 is to handle the transmission of ling access procedures for the "D-channel" (LAPD) on the backhaul line 430, the OTA processor. The exchange of bearer data between card 405 and network-side backhaul components (such as base station controller 112), and multiplexing and demultiplexing of bearer data on backhaul line 430. Other key features of the digital line card 404 are to synchronize the wireless bearer frame timing with the timing on the backhaul line 430 (like the T1 line), to convert OAM &amp; P procedures supported by the network and wireless interfaces. To provide, map an internal base station message (eg I-Note) to and from LAPD transmission over backhaul line 430, and communicate with the OTA processor card 405 for signaling information (eg signaling). Sending and receiving (using I-notes).

The preferred high-level software architecture for base station 401 is illustrated in Figure 5. According to the software architecture illustrated in FIG. 5, the software of base station 401 is divided into two functional groups, one functional group is related to the radio function and the other functional group is the line card function. Involved. These two main functional groups are illustrated in FIG. 5 as OTA management unit 502 and line card management unit 503, each of which preferably operates on its own processor board. Communication between the OTA management unit 502 and the line card management unit 503 can be performed using dual-port RAM (not shown) physically present on the digital line card 404.

The software for OTA management unit 502 and line card management unit 503 can be executed using different processors. For example, in a preferred embodiment, the software for OTA management unit 502 is executed using the MC68430 microprocessor, while the software for line card management unit 503 is executed using the MC68MH360 microprocessor, both of which are Motorola. Manufactured by Corporation. The microprocessor for OTA management 502 is preferably the bus master and has access to dual-port RAM via the global bus (ie backplane). IS-661 signaling messages in I-note format and bearer data are transferred via a dual-port RAM interface, which enables signaling communication between OTA management 502 and line card management 503. ..

The main high-level functions of the OTA management unit 502 are the movement of bearer data between the dual port RAM and the wireless card 406, and the processing of the call control signal system between the line card management unit 503 and the wireless access communication device 412. Is to do. Other functions of OTA Management Unit 502 include wireless resource management, terrestrial resource management, and OAM &amp; P support.

The main high-level function of the line card management unit 503 is the multiplexing and demultiplexing of bearer data between the dual port RAM and the backhaul line 430 (for example, when using the T1 backhaul line, a protocol such as CCITT I.460). (According to), performing LAPD transmission on backhaul line 430 (eg using the Q.921 interface protocol), routing and translating signaling messages between OTA management 502 and backhaul LAPD, and OAM &amp; P support. And include.

The various interfaces associated with base station 401 are graphically illustrated as dotted lines in FIG. 5, and these interfaces are the wireless interface between the wireless access communication device 412 and base station 401 or the "O-interface" 560. An internal interface or "I-interface" between OTA management unit 502 and line card management unit 503, and base station 401 and network-side backhaul components (base station controllers 112, MSC116, and PSTN125 illustrated in FIG. 1). Includes network interfaces or "N-interfaces" between). Yet additional information about these interfaces is described herein and is illustrated at an abstract level in FIG. 10 below.

During operation, base station 401 manages radio resources for the radio access communication device 412, thereby providing network-side support for radio trunk 108 (see Figure 1). A wide variety of different communication methods and radio resource protocols may be used. For example, when base station 401 implements the IS-661 protocol for wireless communication, the base station 401 is the radio between the wireless access communication device 412 and the base station 401, including a time slot and a spread spectrum code. Manage the resources needed to support communication channels. Base station 401 also provides multiplexing capabilities for data transfer to and from backhaul lines that provide connectivity to PSTN125. Base station 401, for example, data on a T1 (or fractional T1) backhaul line 430 to base station controller 112 that pipelines data to and from PSTN125 via MSC116 as described above. Can be multiplexed.

The protocol signaling scheme at the N-interface that connects base station 401 (or 109 in Figure 1) to base station controller 112 (see Figure 1) may be transmission using the LAPD protocol in Q.921. .. Protocol signal transmission over the O-interface, which connects base station 401 to the wireless access communication device 412, can be accomplished using radio signal system messages (O-notes) that follow the IS-661 protocol. The O-note may be transmitted with the bearer data in the IS-661RF packet.

Also, specific software functional components for each of the OTA management unit 502 and the line card management unit 503 are shown in FIG. The OTA management unit 502 includes a signal processing component 513 and an OTA data link component 514 that handle the transfer of bearer data for the OTA management unit 502. Signal processing component 513 and OTA data link component 514 include a protocol state machine for implementing the IS-661 (or other suitable) radio protocol and executing the protocol on base station 401, IS-661. Interacts with protocol component 512. As a result, the signal processing component 513 and the OTA data link component 514 transfer the bearer data and the signal system information in the IS-661 packet 541. The IS-661 protocol component 512 interfaces with the OAM &amp; P component 510 and the I-interface router component 511 to provide any necessary conversion of the signaling scheme to the IS-661 protocol.

The line card management unit 503 includes a signal processing component 523 and a bearer data link component 524 that process the transfer of bearer data for the line card management unit 503. The signal processing component 523 and the bearer data link component 524 have a bearer (eg, in the format of I.460) on the T1 backhaul link 553 with one or more T1 hour slots available on the backhaul line 430. Transfer and receive data 552. Further, the line card management unit 503 includes a LAPD component 522 that transfers and receives a signal system message (for example, N-note) on the LAPD signal system link 551. Therefore, two separate pieces of information "pipes" are provided via the N-interface 562, one for signaling and one for bearer traffic, while the O-interface. Through the 560, the OTA management unit 502 multiplexes the signal transmission and bearer data on the radio channel. LAPD component 522 interfaces with OAM &amp; P component 520 and I-interface router component 521. The I-interface router component 521 of the line card management unit 503 communicates with the I-interface router component 511 of the OTA management unit 502, thereby transmitting an I-note between the line card management unit 503 and the OTA management unit 502. It will be possible to transfer.

Base station 401 connects and manages wireless and terrestrial bearer channels for call-related functions and supports system management via OAM &amp; P controlled by system operators through Operations Management Center 120 (Figure 1). .. As part of its radio resource management function, base station 401 supports (normal and emergency) outgoing voice calls from the radio access communication device 412. Optionally, incoming pages to the wireless access communication device 412 may be supported by base station 401. Since the wireless access communication device 412 may be embodied as a stationary device, the handoff function that would have been needed if it supported a mobile user application supports the wireless access communication device. Therefore, it does not need to be utilized by the base station 401. However, if base station 401 uses a protocol that utilizes TDMA, base station 401 may exchange time slots. It may be configured to support interchange: TSI), which allows traffic in a time slot with unacceptable levels of interference to be relocated to a "quiet" time slot. In the analog system, when FDMA or CDMA technology is used for radio protocols, base station 401 can utilize frequency exchange or code exchange, respectively.

Among other radio resource management functions, base station 401 manages the mapping from radio channels (including the radio communication channels of the radio trunk 108) to terrestrial (ie, backhaul) channels. In addition, the base station 401 supports administrative state change, configuration, and provision of radio resources through the OAM &amp; P function. Base station 401 also provides fault management and alarm management for radio resources and also sends fault or alarm signals to base station controller 112. In addition, the base station 401 controls the signal system flow through the radio interface, manages the power control for each radio channel, recovers the radio link when the radio link is interrupted, and logs debug information to the base station controller 112. provide. As part of power control management for various radio channels, base station 401 may send performance metrics related to radio resources to base station controller 112 for analysis.

When multiple wireless access communication devices 412 are deployed within the service area of base station 401, the base station 401 is generally called from one or more wireless access communication devices 412 due to capacity and traffic constraints. Can be handled. The number of wireless access communication devices 412 depends on the number of wireless channels available in the base station 401 and the amount of traffic when a call request is made to the base station 401. As detailed herein, base station 401 logically assigns a plurality of assigned radio channels to a particular radio access communication device 412 to facilitate processing such as deregistration, if desired. It may be configured to associate with.

For ground resource management, base station 401 manages and allocates backhaul channels (like T1 hour slots) across backhaul line 430. Base station 401 indicates backhaul channel allocation to base station controller 112 through signaling messages. In embodiments where the wireless access communication device 106 is not mobile, base station 401 does not need to support handoff and therefore does not need to support backhaul channel rerouting to perform handoff. OAM &amp; P component 520 of base station 401 provides support for administrative state changes, configuration, and supply of ground resources. It also provides support for performance metrics for ground resources and sends the metrics to base station controller 112. In addition, OAM &amp; P component 520 provides fault management and alarm management for ground resources, which are also sent to base station controller 112. Base station 401 also provides slip management and recovery for T1 backhaul connectivity, bearer rate matching between radio and backhaul channels, and in-bearer data frames to control transcoder device 115. A band signal system is provided.

With respect to call control support, base station 401 is involved in establishing, maintaining, and terminating outgoing voice calls received from wireless access communication device 412. Preferred call flows suitable for those functions are shown in FIGS. 14-19 and are detailed below. If necessary, the base station 401 also relays the DTMF signal system from the end user to the PSTN125 while the telephone call is active. The relay of this signal system is transparently performed through the base station 401, and the signal system is supported by the transfer procedure of the I-interface and the N-interface. Base station 401 also provides digit analysis for outgoing phone calls.

Also, base station 401 preferably provides support for various method security. Base station 401 provides support for bearer encryption performed by, for example, the transcoding device 115 and the wireless access communication device 106. Base station 401 may also support GSM temporary mobile subscriber identity (TMSI) to protect user identity.

With reference to FIG. 1 again, aspects of the base station controller 112 are described here. As described in FIG. 1, the base station 109 is connected to the base station controller 112 beyond an interface such as an N-interface (such as the N-interface described above with reference to FIG. 5). ing. Data (including signaling messages and bearer traffic) is sent across the N-interface between base station 109 and base station controller 112.

The preferred base station controller 112 may, in some embodiments, be considered as a base station subsystem controller used to manage one or more base stations 109. The main task that the base station controller 112 should do is to provide an interface between the MSC116 and the radio access subsystem (ie, the system component responsible for establishing and maintaining physical radio channels). is there. In a preferred embodiment, the base station controller 112 incorporates an IS-661 communication protocol and a GSM communication protocol of a predetermined embodiment, thereby utilizing what may be referred to as a "hybrid" protocol. In another embodiment, the base station controller 112 may be implemented using the IS-661 protocol as a whole or using the GSM protocol as a whole.

According to the IS-661 protocol, radio resource management is performed by base station 109, but does not give the base station controller 112 a significant role. On the other hand, in a GSM system, the base station controller 112 plays a major role in radio resource management and may be seen as essentially equipped with a small switch responsible for radio interface management. In GSM systems, the base station controller 112 allows the base station 109 and the mobile station (as well as the wireless access communication device 106) to be instructed when to assign, hand off, and release radio channels. It is configured with various functions. The interface between base station 109 and base station controller 112 in a GSM system is A._bisCalled an interface.

In communication systems that utilize "hybrid" protocols that have both IS-661 and GSM protocol aspects, the base station controller 112 preferably performs a variety of resource management functions. As part of those functions, base station controller 112 switches bearer circuits and provides bearer connectivity from base station 109 to MSC116 for outgoing voice calls from wireless access communication device 106. Form a path. In addition to switching the bearer circuit, the base station controller 112 provides a signaling path from the wireless access communication device 106 to the MSC116 and other network components. If necessary, the base station controller 112 performs an interconnect between the BSSMAP radio resource management procedure on GSM A-interface 571 and the "N-Note" radio resource management procedure on N-interface 562.

Base station controller 112 is involved in the allocation and release of radio channels. When the IS-661 protocol is used, base station 109 is the entity that actually allocates and releases radio resources. However, as part of the call setup, the base station controller 112 is the entity that coordinates this process. The base station controller 112 also controls the allocation and release of backhaul channels. When the IS-661 protocol is used, base station 109 is the entity that actually allocates bearer resources across the backhaul channel. However, as part of the call setup, the base station controller 112 coordinates this process as well.

The base station controller 112 is also involved in encrypting the transmitted data. Preferably, the transcoding device 115 (FIG. 1) is the network-side endpoint for bearer encryption, while the base station controller 112 sets up and coordinates bearer message encryption.

Predetermined movement management procedures such as authentication and identification are performed end-to-end between the wireless access communication device 106 and the MSC116, and are relayed and transferred via the base station controller 112 essentially without the need for interconnection. .. For other mobility management functions, the base station controller 112 performs the interconnection between the N-interface procedure and the A-interface procedure. For example, the base station controller 112 may relocate or register at the network level (both regular and periodic as detailed herein), deregister and IMSI detach, reallocate time slots, and move. An interconnection may be performed between the N-interface procedure and the A-interface procedure to establish a management connection.

Call control messages and procedures are executed end-to-end between the wireless access communication device 106 and the MSC116 and are transparently relayed via the base station controller 112. In one embodiment, the base station controller 112 provides a signaling path between the wireless access communication device 106 and the MSC 116 to perform call control signaling.

The base station controller 112 may support a variety of interfaces. Preferably, the base station controller 112 supports a T-interface to the transcoding device 115, or is an integrated base station controller if the transcoding device functionality is integrated with the base station controller 112. / Supports GSM A-interface 571 between transcoding equipment and MSC116. In another direction, and preferably, the base station controller 112 supports N-interfaces connected to various base stations 109.

In a preferred embodiment, as shown in FIG. 1, the base station controller 112 transmits and receives information to and from the transcoding device 115. In some embodiments, the transcoding apparatus 115 includes an entity of a base station subsystem (BSS) provided between the base station controller 112 and the MSC 116 in one embodiment. Preferably, the transcoding device 115 is under the control of the base station controller 112, but is physically located inside the MSC116, whereby the base station controller 112 is located remotely from the location of the MSC116. Can be done. The transcoding device 115 includes a plurality of transcoding devices in a shelf shape, which are under the control of the base station controller 112 but operate independently of each other. In a preferred embodiment, each shelf-shaped transcoding device supports up to 92 bearer channels.

The transcoding device 115 generally performs network-side processing of the key function on the bearer path. This process may include, for example, voice transcoding, network side forward error correction (FEC), and network side encryption and decryption of bearer voice.

With respect to voice transcoding capabilities, the transcoding device 115 preferably has coded voice data received from the user side and "μ-method" coded pulse code modulation (PCM) data received from the network side at 64 kilobits / second. Provides bidirectional conversion between and. The vocoder 206 (see FIG. 2) on the wireless access communication device 106 compresses the voice received from the CPE 105 for wireless transmission to the network. In the opposite direction, the vocoder 206 on the wireless access communication device 106 decompresses the radio voice before transmission to the CPE 105.

Preferably, the transcoding device 115 includes, among other things, a voice encoder and a voice decoder. The voice encoder in the transcoding device 115 receives the PCM voice data sent from the network at 64 kilobits / second and sends this data to the wireless access communication device 106 in a low-rate radio channel. Compress to. Forward error correction (FEC) information is added separately by the transcoding device 115 by the FEC function. The voice decoder at the transcoding device 115 processes the compressed voice data from the wireless access communication device 106, transcodes this data, and transmits it to the MSC116 at 64 kilobits / second of PCM voice. Generate data. The audio decoder in the transcoding apparatus 115 further provides an interpolation function, which allows the expected audio pattern when the base station 109 detects a frame containing an error that cannot be corrected by the forward error correction function. Output. The audio decoder in the transcoding device 115 also provides a mute function for muting the output to the A-interface when needed, such as during transmission of control traffic.

With respect to forward error correction (FEC), in the user-to-network direction, FEC information is added on the message by the wireless access communication device 106. The channel decoding function in the base station controller 112 and / or the transcoding device 115 uses FEC information to detect the presence of an error and estimate the most likely transmitted bit based on the received bit. I do. In the network-to-user direction, the base station controller 112 and / or the transcoding device 115 applies forward error correction to the frames received from the vocoder processing function before the frames are sent over the N-interface. FEC decoding in the direction from the network to the user is performed by the wireless access communication device 106.

For encryption and decryption capabilities, the bearer encryption (encryption or ciphering) mechanism used in this system is preferably based on the GSM A5 / 1 algorithm. The GSM A5 / 1 algorithm is a well-known algorithm in the art. For bearer voice, the two endpoints in the system for encryption and decryption are the wireless access communication device 106 and the transcoding device 115. Here, communication is divided into multiple time frames and multiple time slots (as seen in some types of time division multiple access or TDMA systems), and encryption and decryption is done frame by frame.

In the wireless access communication device 106 and the transcoding device 115, preferably, the number of frames used by the wireless access communication device 106 for encryption of one frame is the same as the number of frames used by the transcoding device 115 for decryption, and vice versa. Is also in a state of "encryption synchronization" in the same sense. GSM The A5 / 1 algorithm involves generating a frame-by-frame encryption / decryption mask based on the number of frames. Typically, the establishment and re-establishment of cryptographic synchronization is a loss of cryptographic synchronization during call setup and due to error conditions (whether occurring on a wireless link or a backhaul link). It is done when you recover from. Once cryptographic synchronization is established (or optionally reestablished), the wireless access communication device 106 and the transcoding device 115 increase the number of frames for each frame cycle of the wireless interface and the backhaul interface. .. Preferably, the same frame length (eg, 20 ms) is used for both radio time frames and backhaul time frames, where each frame cycle is typically encrypted / when increasing the number of frames. Keeps the number of frames synchronized between the two endpoints of the decryption function.

The transcoding device 115 may support various interfaces. The transcoding device 115 may support an A-interface that links the transcoding device 115 in the MSC116 and a T-interface that links the transcoding device 115 to the base station controller 112. The T-interface transmits bearer voice data. The bearer audio data is processed by the bearer function of the transcoding device and relayed to the MSC116 on the A-interface together with the A-interface signal system via the SS7 link. Preferably, the transcoding apparatus 115 provides signal-based transparent passthrough between the base station controller 112 and the MSC116 via the SS7 link and optionally via an X.25 or similar type of link. The T-interface is also with the transcoding device 115 for signal transmission for OAM &amp; P control of the transcoding device 115 and for dynamic per-call control of the transcoding device function. In-band signal transmission with the base station controller 112 is performed. The signal scheme exchanged between the transcoding device 115 and the base station controller 112 is centralized in a specific time slot (eg, the first time slot of the time frame) and is a link access procedure (LAPD) for the D channel. Controlled using level 2 of the protocol.

FIG. 9 is a high-level diagram showing the preferred division of bearer path function performed by the wireless access communication device 106, base station 109, base station controller 112 and / or transcoding device 115. As shown in FIG. 9, the bearer path function 901 of the wireless access communication device provides voice coding and decoding 911, forward error correction (FEC) 912, encryption and decryption 913, and tone generation 914. Including. Base station bearer path function 902 includes backhaul framing 921 and channel multiplexing and multiplexing 922. The bearer path function 903 of the base station controller and transcoding device provides voice coding and decoding 931, forward error correction (FEC) 932, encryption and decryption 933, backhaul framing 934, and channel multiplexing. Includes Cryptography and Multiplexing 935. These features have been previously described in relation to the various components of the system and are described in various detail elsewhere in this specification or in the material incorporated herein for reference. , Further explained.

As shown in FIG. 9, the voice coding / decryption, encryption / decryption and FEC functions performed in the wireless access communication device 106 are similarly provided in the base station controller 112 and / or the transcoding device 115. Be done. The channel multiplexing / multiplexing and backhaul framing functions performed at base station 109 are similarly provided by base station controller 112 and / or transcoding device 115.

Referring again to FIG. 1, the transcoding device 115 is connected to the Mobile Exchange Center (MSC) 116 and the MSC 116 is connected to the PSTN 125. The MSC116 is a cellular switch that acts as an interface between a base station subsystem (BSS) and PSTN125 and acts as a gateway to long-range networks. The MSC116 has telephone exchange capabilities, including call setup, routing selection, exchange between incoming and outgoing channels, communication control and release of connections. In addition, the MSC116 performs the above functions in consideration of subscriber mobility management, including authentication, encryption, radio resource management and location registration update procedures. The MSC116 also allows the wireless access communication device 106 to interconnect with the PSTN125. The MSC116 is a digital multiplex system capable of providing exchange capabilities in cellular networks. It may be part of an exchange system based on the "supernode" of system: DMS). Also, preferably, the visitor location register (VLR) is co-located and integrated with the MSC116.

The MSC116 may support a variety of interfaces. The MSC116 may support A-interfaces and PSTN interfaces. The A-interface provides a linkage between MSC116 and a base station subsystem (BSS), in particular a linkage between base station controller 112 and transcoding device 115. The PSTN interface is used to connect the MSC116 to the PSTN125. Voice and circuit traffic is transmitted across the MSC116 and PSTN125. MSC116 is also a mobile application part: MAP) interface may be supported. The Mobile Communications Application (MAP) interface is a CCS7 application that allows mobile information to be transferred between network-level components. In addition, the MSC116 may support a billing center interface, an operations management center (OMC) interface, and a service center interface. The billing center interface is used to connect the MSC116 to a downstream processor for downloading billing events. The Operations Management Center (OMC) interface is used to manage the MSC116 and the Visitor Location Register (VLR). The service center interface is used to connect the functions of the service center responsible for relaying short messages to mobile stations and storing and forwarding them.

Preferably, the MSC116 performs a variety of functions. For example, preferably the MSC116 authenticates the subscriber and, if the system is accessible, the mobile station. The MSC116 can interface with the PSTN125, for example, the public land mobile network (PLMN) or the PCS-1900 network. The MSC116 also provides terrestrial channel allocation and call control and signaling support. In addition, the MSC116 can perform echo cancellation processing to the PSTN125, handle and manage database information, billing records, handle subscriber registration and location management, and measure operation.

The MSC116 is connected to the Home Location Register (HLR) and Authentication Center (AuC), which are collectively shown in Figure 1 as the integrated device HLR / AuC123. The HLR / AuC123 can be built on a digital (eg DMS) supernode platform and is interconnected with various functional entities. Functional entities include visitor location registers, MSCs and mobile communications applications (MAP). The HLR component of the HLR / AuC123 supports information about subscribers, information about services assigned to subscribers, information about the status of such services, and the behavior of services when they are started. Contains more information required for. HLR provides or updates subscriber data in response to requests from MSC116 and / or VLR. The HLR communicates with the VLR to download subscriber data and obtain call routing information for mobile stations in the area covered by the VLR.

The AuC component of the HLR / AuC123 contains a subscriber key used when attempting to authenticate to access the network. The AuC component uses the subscriber key to generate an authentication vector. The authentication vector is provided to the VLR via the HLR component. Further details regarding authentication have already been described and will be understood from the above description.

In mobile systems such as the PCS1900 mobile system, the information held by the HLR component of the HLR / AuC123 allows mobile stations to be addressed using unique numbers, regardless of their geographical location. Becomes possible. Therefore, mobile stations can roam freely within and between networks. In systems that provide fixed access radio services that utilize the wireless access communication device 106 and related components, the HLR components are similar to those held for mobile stations in a system that is entirely mobile-based. Contains information. The HLR component of the HLR / AuC123 contains information about the subscriber interfaced with the wireless access communication device 106. As previously described, the individual CPE trunks connected to the wireless access communication device 106 (eg, the CPE trunk 602 shown in FIG. 6) are individual subscribers (ie, "mobile stations") for the HLR and HVR. ). Therefore, each CPE trunk connected to the wireless access communication device 106 has its own (preferably unique) subscriber identification number. The subscriber identification number may include the International Mobile Subscriber Identifier (IMSI) as previously described. The International Mobile Subscriber Identifier (IMSI) is a unique and permanent identifier for the CPE trunk assigned at the time of manufacture of the CPE105. Alternatively, the subscriber identification number may include a mobile subscriber ISDN (MSISDN) number. The mobile subscriber ISDN (MSISDN) number is one of the public PSTN numbers assigned to CPE105.

The wireless access communication device 106 is such that the wireless access communication device 106 is non-mobile, because the wireless network is probably configured to serve individual mobile subscribers in addition to being able to serve the wireless access communication device 106. Aspects can include the ability to remain transparent from the wireless network. For example, mobile subscribers may often signal the wireless network and refresh the VLR on a regular basis. In order to maintain the fixed radio aspect of the system to be transparent from the wireless network, the wireless access communication device 106 periodically performs network level registration, for example using a GSM periodic registration mechanism, and "subscribes". The VLR entry for "person" may be kept in a valid state. The wireless access communication device 106 also performs network-level registration each time registration is made via base station 109 in a location area different from the previously connected location area of base station 109. Details regarding initial registration and regular registration are described above.

Certain features related to the establishment and maintenance of voice calls will be described in more detail below. Here, the interaction between various components of the communication system in which the wireless access communication device 106 is deployed is referred to.

With respect to the establishment of the "outgoing" voice call made by the CPE 105, the wireless access communication device 106 handles the acquisition of wireless communication channels, mobility management connectivity, and call setup, plus various errors or exceptions, preferably. Has the ability to handle situations. When the wireless access communication device 106 detects trunk capture by the CPE 105, the wireless access communication device 106 marks the CPE trunk as "busy" and outputs a dial tone (assuming that it can communicate with the base station 109). .. At the same time, the wireless access communication device 106 starts the wireless communication channel acquisition procedure. If the wireless access communication device 106 detects the first digit dialed from the CPE 105, or detects an on-hook from the CPE 105 before receiving any digit from the CPE 105, the dial tone is removed.

To facilitate the initial acquisition of wireless communication channels, the wireless access communication device 106, when first activated, preferably performs a detailed search for nearby base stations 109 to find a suitable base station 109. The wireless access communication device 106 establishes communication with the base station 109 and receives a map of surrounding base stations from the current base station 109. The peripheral base station map provides the wireless access communication device 106 with a list of nearby base stations 109. The list of nearby base stations 109 is a candidate for wireless communication. Using the surrounding base station map, the wireless access communication device 106 creates a base station selection table. The base station selection table includes signal quality information and the like regarding neighboring base stations 109. The base station selection table is stored in the non-volatile memory of the wireless access communication device 106. When the power is subsequently turned on, the wireless access communication device 106 utilizes the existing base station selection table in order to quickly acquire the base station.

When a trigger for setting up or registering an outgoing call is received from the CPE 105, the wireless access communication device 106 attempts to acquire a wireless communication channel. In a given wireless system, the acquisition of wireless communication channels is achieved by interacting with the control channels of the wireless system. In some types of TDMA systems, the channel acquisition process involves the acquisition of time slots within the time frame established by base station 109. The acquisition of time slots may be performed according to, for example, the handshake protocol described in detail in Patent Document 6.

If the wireless access communication device 106 cannot find an available wireless communication channel to communicate with the base station 109, then the next action of the wireless access communication device 106 is whether there are other active calls. , Or the presence or absence of other calls set up by the wireless access communication device 106. If there are no other active calls and no other calls set up by the wireless access communication device 106, the wireless access communication device 106 can find a base station 109 with which the wireless access communication device 106 can communicate. , Explore the surrounding area. If a suitable base station 109 is found (eg, based on received signal quality or traffic availability), the radio access communication device 106 attempts to acquire a radio communication channel at the new base station 109. (For example, in certain embodiments, the wireless access communication device 106 is a general polling message transmitted within a time slot. You may look for message). Here, the general-purpose polling message indicates the availability of a radio time slot for communication, as described in Patent Document 6 of the above reference. If the wireless access communication device 106 fails to acquire the wireless communication channel, it may try to acquire it again, or it may search for a different base station 109. The wireless access communication device 106 continues this process until it finds that the wireless access communication device 106 has acquired the wireless communication channel or that the link establishment timeout period has expired, that is, the acquisition of the wireless communication channel has failed.

There are other calls that are active or set up by the wireless access communication device 106 when an attempt to acquire another radio communication channel with the current base station 109 is unsuccessful. If so, the wireless access communication device 106 indicates that the attempt to acquire the channel is unsuccessful. Alternatively, the wireless access communication device 106 may attempt to set up a call for different base stations 109, thereby maintaining communication with two different base stations 109 at the same time (one, but Handles the currently active call, and the other handles the latest call).

If the attempt to acquire the radio communication channel is unsuccessful, the radio access communication device 106 outputs a "reorder" sound in the CPE trunk and marks the radio communication state as "congestion". If the wireless access communication device 106 has a ground start trunk interface to the CPE 105, the wireless access communication device 106 captures the empty CPE trunks (ie, grounds the tip at each CPE trunk 602) to those CPEs. Make the trunk busy. As long as the congestion state is continuing, CPE 105 may then route the call would have been directed to the wireless access communication unit 106 to PSTN125 (assumed to CPE 105 may routability call) to so. If in a "congested" state, the radio access communication device 106 continues to track the radio channels available at the current base station 109. If the congestion condition is cleared (for example, the wireless access communication device 106 can check the general-purpose polling message from the base station 109, or provide information indicating that the communication channel is available from the base station 109. The wireless access communication device 106 marks the wireless communication state as "non-congested" (if it can be received). If the wireless access communication device 106 has a ground start trunk interface to the CPE 105, the wireless access communication device 106 removes all CPE trunks from the busy state by releasing the CPE trunks (that is, removing the tip from the ground). To release.

If the acquisition of the wireless channel is successful, the wireless access communication device proceeds to the transmission and analysis of the digit. Upon detecting the first dialed digit, the wireless access communication device 106 removes the dial tone and initiates the digit analysis procedure. In a preferred embodiment, the digit is relayed and received from the wireless access communication device 106 after the wireless communication channel is established, and the digit analysis is performed at the base station 109. Base station 109 stores the digits, analyzes the digits, and determines the type of call and the end of the dial sequence.

In an exemplary embodiment, base station 109 analyzes digits as follows: When "X" is "4" or "9" and the base station 109 detects the digit pattern "X11", it is determined that the dialing is completed. If the digit sequence is "911", base station 109 marks the call type as an emergency call. All other types of calls are marked as regular calls. If the first three digits are not "411" or "911", base station 109 continues to receive the digits and uses the dial completion timeout period (eg 4 seconds) to detect the end of the dial. To use the dial completion timeout period, the dial timer is activated when the first digit is received by base station 109, and the dial timer is reset each time a new digit is received. When the dial timer counts up to the dial completion timeout period, the base station 109 determines that the dial has been completed.

When it is determined that the dial sequence is completed, the base station 109 issues a trigger to the wireless access communication device 106 to continue establishing the call. Establishing this call involves establishing a mobile management connection and setting up the call. This trigger also indicates the type of call (that is, normal or urgent).

Some types of exceptions or errors can occur when trying to establish a communication path from the user (ie, telephone station device 102) to base station 109. For example, if the wireless access communication device 106 is unable to communicate with the base station 109, the wireless access communication device 106 does not generate a dial tone. Instead, the wireless access communication device 106 outputs a reorder sound to the user via the CPE 105. If, after the trunk capture is recognized by the wireless access communication device 106, no digit is received by the wireless access communication device 106 for a predetermined timeout period, the trunk is subjected to handset off signal processing as described below. Do (that is, treat the trunk as if it were in an extended off-hook state). If the dialing from the user is incomplete, or if the dialed number is invalid, the MSC116 will do the right thing. In such a situation, the base station 109 generally detects the end of the dial and triggers the setup of the call by the wireless access communication device 106. An incomplete or invalid digit sequence is written by base station 109 to the DTAP setup message and sent to the MSC116. When an exception situation is detected in the digit analysis performed on the MSC116, the MSC116 returns a DTAP Release Complete message to the wireless access communication device 106. This DTAP release complete message indicates that the dialed number is invalid.

If the wireless access communication device 106 loses communication with the base station 109 currently in use, or the quality of one or more wireless communication links is the minimum acceptable minimum (eg, high bit error rate, etc.) Below (based on signal weakness), the wireless access communication device 106 initiates a base station acquisition procedure for determining a base station 109 capable of communicating with sufficient quality. For a ground-start trunk interface between wireless access communication device 106 and CPE 105, wireless access communication device 106 attaches those CPE trunks by capturing the CPE trunks, that is, by grounding the tip at each CPE trunk 602. Make it busy. When the reacquisition of the base station is complete (either by reestablishing communication with the current base station 109 or by discovering a sufficiently strong RF link with a different base station), the wireless access communication device 106 Releases the busy CPE trunk from the busy state when communication with base station 109 is lost or interrupted.

In another aspect of the invention, even though multiple CPE trunks are physically connected to the wireless access communication device 106, the CPE trunks supported by the wireless access communication device 106 each correspond to a logical subscriber to the network. To do. So, for example, if four CPE trunks 602 are connected to wireless access communication device 106, four unique subscriber identifiers will be assigned. By using a different logical subscriber identifier for each CPE trunk 602, the wireless access communication device 106 can handle multiple calls over one or more wireless links to base station 109. In certain embodiments, each CPE trunk 602 is identified using its own International Mobile Subscriber Identifier (IMSI) number and Mobile Station ISDN (MSISDN) to specify the address. When the wireless access communication device 106 initiates a "mobility management" procedure and a call control procedure on behalf of one of the connected CPE trunks, the wireless access communication device 106 uses the IMSI assigned to that CPE trunk. To do.

On the network side of the system (base station 109, base station controller 112, MSC116, etc.), each logical subscriber associated with the wireless access communication device 106 is a separate mobile that can also wirelessly communicate with the base station 109. Recognized as separate users as if they were subscribers. Base station 109 usually does not need to know different groups of IMSIs that belong to one entity (ie, wireless access communication device 106). The IMSI is preferably held on one or more factory-programmed subscriber interface module (SIM) 606 chips. Each SIM606 chip belongs to a particular CPE trunk once placed on the wireless access communication device 106. As described elsewhere herein, the IMSI is used for registration, authentication, and network access.

Each IMSI stored in the wireless access communication device 106 preferably corresponds to the MSISDN stored in the HLR component of the HLR / AuC123. The MSISDN number may be the equivalent of the NANP number converted to the MSISDN number, i.e. a number having the format 1 + NPA + NXX + XXXX. The MSISDN number is used for making calls and generating billing information (billing). The MSISDN number may be one of the public PSTN numbers assigned to CPE105. Therefore, MSISDN numbers may be assigned from PSTN125 to CPE125.

The wireless access communication device 106 may be assigned an identification serial number in the form of an International Mobile Equipment Identity (IMEI) number. The IMEI number may be assigned at the factory, preferably each wireless access communication device 106 is associated with a unique IMEI number. If the Equipment Identity Register (EIR) element is used in the network, the Equipment Identity Register element contains the IMEI number of each wireless access communication device 106 in the system. The alarm generated by the wireless access communication device 106 may use the IMEI number for identification purposes.

As previously described herein, the present invention provides, in one embodiment, a technique of signal schemes and protocols for facilitating communication in systems with wireless trunks. Signaling information is transmitted using one or more different interfaces of communication system 101 so that communication between CPE105 and PSTN125 can take advantage of the capabilities of wireless access communication device 106. To. In a preferred embodiment, communication system 801 utilizes a "hybrid" protocol by incorporating aspects of the IS-661 communication protocol (or a modified version thereof) and aspects of the GSM communication protocol.

Various aspects of IS-661 are summarized as follows. According to the IS-661 protocol, wireless communication between base station 109 and mobile stations or other user stations is performed by using frequency division multiplexing (FDD). At this time, the base station 109 transmits a signal through the frequency band of the base station, and the mobile station or other user station transmits a signal through the frequency band of the mobile station / user station. Multiple transmissions are distinguished according to time slot, where the TDMA time frame in each of the base station frequency band and the mobile / user station frequency band contains 32 time slots, each of which is 625 microseconds. As a result, the duration of the TDMA time frame is 20 milliseconds. (However, in one variant, 16 dual communication time slots are used.) The preferred operating frequency is 1850 to 1990 MHz, and the size of the step size adjusted by the synthesizer is 100 kHz. Communication is performed using spread spectrum communication with an RF channel spacing of 1.6 MHz. Spectral diffusion modulation may be MSK or OQPSK with pulse waveform shaping performed by using a root raised cosine method. Preferably, the chipping rate of spectral diffusion is 1.25 M chips (Mcps) on each of the two channels, i-channel and Q-channel. The system may perform antenna diversity. In addition, the system may perform power control of the mobile station or other user station in predetermined steps (eg, 3 dB).

Different interfaces in a communication system may use different protocols, depending in part on where the interface is in the chain of communication paths. FIG. 10 is a diagram showing an interface between different components in the communication system 801 according to a preferred embodiment of the present invention. Some of these interfaces have been outlined earlier with respect to the preferred base station 109 shown in FIG. The various interfaces shown in FIG. 10 are the wireless interface or "O-interface" 560 between the wireless access communication device 106 and the base station 109 and the inside of the base station 109 (ie, as shown in FIG. 5). In addition, the internal interface or "I-interface" 561 of the line card management unit 503 and OTA management unit 502 of the preferred base station 501 and the network interface or "N" between the base station 109 and the base station controller 112. -Includes "Interface" 562. Base station controller 112 communicates with MSC116 via a standard interface such as GSM A-interface 571.

In a preferred embodiment, a transcoding unit 115 is inserted between the base station controller 112 and the MSC 116 according to the embodiment of the invention shown in FIG. In this embodiment, an additional interface, called a "T-interface", is provided between the base station controller 112 and the transcoding device 115, the transcoding device 115 being like the GSM A-interface 571. Communicates with MSC116 through a standard interface.

Each of the communication interfaces shown in FIG. 10 will first be described in more detail from the "O-interface" 560 between the wireless access communication device 106 and the base station 109. The "O-Interface" 560 is one or more wireless, It has over-the-air) communication channels, each channel preferably (but not required) having a forward communication link and a reverse communication link to support full-duplex communication. doing. One or more radio communication channels of the O-interface 560 include protocols that utilize time division multiple access (TDMA), frequency division multiple access (FDMA) or code division multiple access (CDMA) or various combinations thereof. , May be implemented by any of a variety of different multiple access communication protocols. The O-interface 560 may have a radio broadcast channel from base station 109 used, for example, to carry control traffic and signaling information in some other embodiment. Good. In other embodiments, no dedicated broadcast control channel is used.

In a preferred embodiment, the base station 109 is part of a cellular network that utilizes various aspects of FDMA, TDMA and CDMA for cell isolation. In an exemplary embodiment, multiple user stations are separated and multiple access is achieved by TDMA. Frequency division multiplexing (FDD) Duplexing) is adopted to allow 16 full-duplex user stations to share a common RF radio frequency. In the cellular network, adjacent cells receive one of the nine frequency channels and use seven code reuse patterns, thereby achieving isolation between the cells. Direct spread spectrum spread transmission is used by the base station 109 and the user station in the cell including the wireless access communication device 106. Spectral spread communication reduces interference between cells and interference with other systems operating within the same neighborhood (eg, PCS systems). Multiple cells in an adjacent cluster use a variety of coherence techniques, including orthogonal or substantially orthogonal diffusion codes, line code control, directional antennas and time slot mutual exchange (TSI).

FIG. 25 shows one possible communication protocol that can be used to communicate through the O-interface 560 in one embodiment of the invention. The protocol shown in FIG. 25 uses time division multiple access (TDMA) and spectral diffusion techniques. As shown in FIG. 25, the polling loop 1380 (major frame) has multiple time slots 1381 (minor frame). Each minor frame 1381 has time division duplex communication between a base station 109 (eg, a cellular station) and a user station (eg, a mobile user). That is, within the same minor frame 1381, the base station 109 transmits to the user station, and the user station conversely transmits to the base station 109.

More specifically, as shown in a partial exploded view of the polling loop 1380 in FIG. 25, the minor frame 1381 has a mobile station or user station transmission 1382 before the base station transmission (base transmission) 1383. The minor frame 1381 also has a variable radio delay gap 1384 before the user station transmission 1382, and after the user station transmission 1382, a turn around gap 1388 and a guard time gap (guard). time gap) 1389 follows. The gap 1389 is followed by a base station transmission 1383, which is followed by another turnaround gap 1393. The user station transmission 1382 includes a preamble 1385, a preamble sounding gap 1386, and a user message. It has an interval) 1387. The base station transmission has a preamble 1390, a preamble sounding gap 1391, and a base station message section 1392.

FIG. 26 shows other communication protocols that can be used for communication through the O-interface 560. The protocol shown in FIG. 26 is an embodiment of both FDMA (in the sense that multiple transmissions are distinguished by different frequency allocations) and TDMA (in the sense that multiple transmissions are distinguished by different time allocations). Is used. As shown in FIG. 26, one frequency band 1510 is assigned to base station 109 for transmission from the base station to the user station, and another frequency band for transmission from the user station to the base station. 1511 is assigned to a user station (eg, a mobile phone (handset) or other wireless device). Repeating major time frames (or "polling loops") 1501 are defined for communication in each frequency band 1510, 1511. Within the repeating major time frame 1501, multiple (eg, 16) base station time slots 1502 and user station time slots 1503 are defined, wherein preferably the user station time slot 1503 is in base station time slot 1502. On the other hand, it is delayed by a certain amount of time.

In a preferred embodiment in which 16 base station time slots 1502 and 16 user station time slots 1503 are defined in each major time frame 1501, a first base station time slot 1502 and a first user station time slot 1502 are defined. The time delay 1505 with and from 1503 is a preset amount of time corresponding to a predetermined number of time slots, such as eight time slots, and is therefore referred to as a "slot offset". This time delay, or slot offset 1505, allows the user station time to receive transmission signals over the base station frequency band 1510 in the allocated base station time slot 1502 and to process transmissions from the base station to the user station. It is now possible to switch the transmit / receive frequency and transmit the reverse link in the corresponding user station time slot 1503 without having to wait for the entire time frame duration to transmit the reverse link. Become. The slot offset 1505 may have a time amount other than the eight time slots, or the major time frame 1501 may be defined so that the slot offset 1505 is completely absent.

Alternatively, instead of having a fixed time delay or slot offset 1505, the base station time slot 1502 and the user station time slot 1503 can also be assigned independently of each other, where the base station time slot 1502 The spacing between and the corresponding user station time slot 1503 (ie, the pairs that make up dual communication) is dynamically selected, for example, based on the type of user.

In a preferred embodiment, one or more user station time slots 1503 and one or more base station time slots 1502 assigned to the wireless access communication device 106 transmit / transmit the radio transceiver in the wireless access communication device 106. It is offset by a sufficient amount of time to allow switching of the reception frequency. In one embodiment, the wireless access communication device 106 takes about 625 microseconds to switch between transmit and receive frequencies. This time corresponds to half the duration of the time slot when the time slots 1502 and 1503 are each 1.35 milliseconds in length. Here, preferably, an 8-slot offset is provided between the base station time slot 1502 and the corresponding user station time slot 1503 to form a "virtual" time slot. The 8-slot offset, for a preferred embodiment, for each wireless access communication device 106 in the available wireless slot space, while reducing the potential number of transmission / reception frequency switchings by the wireless access communication device 106. It is believed to be sufficient to accommodate four trunks.

According to one embodiment, the wireless access communication device 106 transmits a slot allocation map to the base station 109 when negotiating slot allocation with the base station 109. The slot allocation map shows which radio slot has already been allocated for the call in the wireless access communication device 106. The base station 109 draws the base station time slot 1502 and the user station time slot 1503 from the pool of available time slots 1502, 1503 by using the information of the slot allocation map. The base station 109 makes this selection, for example, based on the limitation of the transmission / reception switching time of the wireless access communication device 106.

In one aspect of a preferred communication protocol, a single base station time slot 1502 and a single user station time slot 1503 together constitute one dual communication channel. In a preferred embodiment, the protocol time frame 1501 described with respect to FIG. 26 spans a total of 16 possible dual communication channels, with 16 base station time slots 1502 and 16 corresponding user station times. Supports slot 1503. In a preferred embodiment, each base station time slot 1502 and user station time slot 1503 has a duration of 1.35 ms, and each time slot contains 9.6 kilobits of encoded voice or other data. It enables transmission in seconds.

The number of wireless access communication devices 106 that can be supported by a single base station 109 is generally the number of communication channels available at base station 109 and the communication channels required by the wireless access communication device 106 (ie, the CPE trunk). ) Is a function related to the number. For example, if 16 communication channels are available at base station 109, and each radio access communication device 106 has four CPE trunks 602, base station 109 supports four wireless access communication devices 106. Each of them operates at maximum capacity in a given time. However, when the wireless access communication device 106 is expected to operate below the maximum capacity for a predetermined period of time, and based on the blocking requirements and the expected subscriber load, the wireless access communication device 106 shares the base station 109 as a resource. More than four radio access communication devices 106 may be assigned to a single base station 109 for use as. In addition, base station 109 may communicate with one or more wireless access communication devices 106 and at the same time with other wireless users, such as mobile phones or other wireless devices.

The communication channel is preferably assigned to the wireless access communication device 106 on demand, but in some embodiments it may be pre-allocated. The advantage of dynamic allocation of wireless communication channels is that more users can be supported. With respect to the protocol shown in FIG. 26, the radio communication channel is preferably assigned based on the request from the radio access communication device 106 to the base station 109. Radio communication channel allocation is performed similarly for mobile users (if any) who also communicate with base station 109, i.e. according to the cellular communication protocol for networks that include base station 109 in part. To. For example, the wireless communication channel may be assigned with the assistance of a dedicated control channel. In addition, a mechanism for allocating or designating any other radio communication channel may be used as appropriate.

While the O-interface 560 generally includes a direct wireless interface between the wireless access communication device 106 and the base station 109, some other interface, as detailed in FIG. 10, exchanges information with the PSTN125. It is needed when you do. The next interface when proceeding to PSTN125 is the I-interface 561. The I-interface 561 is inside the base station 109 and generally performs the conversion of radio messages into a format particularly suitable for backhaul transmission to the network and vice versa. Further details of the I-interface 561 are described with reference to FIG.

The next interface from the wireless access communication device 106 to the PSTN 125, as shown in FIG. 10, is the N-interface 562, which connects the base station 109 to the base station controller 112. The N-interface 562 has traffic and signaling communication channels, as further described herein. At the physical layer, the N-interface 562 utilizes the fractional T1 service as a transport mechanism. Each fractional T1 link supports transfer rates from 64 kilobits / second to 1.536 megabits / second. Each time slot on the T1 link supports up to four 16-kilobit / s bearer channels.

The traffic channel of N-interface 562 has an unaggregated 16 kilobit / sec channel for transmitting data (eg, voice data) of one radio traffic channel (ie, one radio communication channel). Up to four such traffic channels can be multiplexed into one 64 kbps T1 hour slot. A single signal channel is provided for each base station 109 to transmit signaling and OAM &amp; P information at a rate of 64 kilobits / second. The signal system traffic has control information belonging to the link between the base station 109 and the base station controller 112, similar to the signal system traffic relayed between the wireless access communication device 106 and the MSC 116.

LAPD terminal identifiers (TEIs), local management terminals (if provided) and base stations, are used to manage signal transmission through the N-interface 562 and operational or administrative message transmission. It is used for the transfer of signal system and OAM &amp; P information between the base station controller 112 and the base station 109 together with the control information between the 109 and the base station controller 112. The TEI is preferably assigned to base station common functions (see Figure 7, see below) and transceivers that send and receive messages on the N-interface 562. The base station common function TEI is permanently assigned to the T1 hour slot on the N-interface 562 and is derived from the number of T1 hour slots. The transceiver TEI is semi-permanent and is determined from the configuration parameters. The above base station common functions and different functional entities in the backhaul transceiver are service access point identifiers. Addresses are specified using identifiers: SAPI). In certain embodiments, a single backhaul transceiver is supported by base station 109, thus in such embodiments, only one transceiver TEI is used.

FIG. 7 shows in more detail an interface signaling configuration for the N-interface 562 used in connection with a preferred embodiment of the present invention. As shown in FIG. 7, the base station controller (BSC) 702 is connected to the base station (OBTS) 703 over multiple logical links 711 to 715, all of which are physical. From a clear point of view, it is multiplexed onto a single digital time slot channel (or DS0) and transmitted using pulse code modulation (PCM). The base station 703 shown in FIG. 7 is identified by two transceivers 706,707 (denoted as "TRX1" and "TRX2" respectively), respectively, identified by the terminal endpoint identifiers TEI B and TEI C, and by the terminal endpoint identifier TEI A. It has a base station common function (BCF) 705 to be identified.

Logical links 711 to 715 can be categorized by service access provider identifier (SAPI) type. For example, in the embodiment shown in FIG. 7, the SAPI type "62" indicates ОAM &amp; P signaling and the SAPI type "0" indicates traffic signaling. One ОAM &amp; P SAPI logical link 712 and one traffic signaling logical link 713 are logically associated with one transceiver 706, as described in the interface signaling configuration shown in Figure 7. One ОAM &amp; P SAPI logical link 714 and one traffic signaling logical link 715 are logically associated with the other transceiver 707. The third ОAM &amp; P logical link 711 is logically associated with the base station common function unit 705.

Signaling messages for traffic control are transmitted over two logical links 713 and 715 connected to transceivers 706 and 707, respectively. Signaling messages carried by logical links 713 and 715 for interaction between base station 703 and base station controller 702 relate to features such as backhaul and radio resource management and mobility management. It was done. The signaling messages transmitted by channels 713 and 715 are also related to the end-to-end call control and mobility management signaling between the wireless access communication device 106 and the MSC116, and within the forwarding note. It is encapsulated in. In addition, the observation counter and operation measurement sent by base station 703 to base station controller 702 and encapsulated in transfer notes shall be transmitted over logical links 713 and 715. Can be done.

Messages related to management functions (such as ОAM &amp; P) are transmitted over logical links 711, 712 and 714 to base station common functions 705 and transceivers 706 and 707, respectively. ОAM &amp; P message transmission is performed for the management of base station 703 by the base station controller 703.

In a preferred embodiment, the base station controller 112 transcodes through a T-interface. It is connected to unit) 115, which is shown in Figure 1 but not explicitly in Figure 10. The T-interface links the base station controller 112 to the transcoding device 115 through a T1 connection that carries a variety of different links, including bearer voice channel links and signaling links. The T-interface provides encoded and encrypted voice and in-band signaling information between base station 109 and transcoding device 115 (ie, the endpoint of the encryption / decryption algorithm). Deliver multiple 16 kilobits / sec bearer audio channels containing FEC information. In one embodiment, up to four such bearer audio channels can be multiplexed on one DSО time slot. The bearer voice channel is processed by the transcoding device 115 for transcoding and speed adaptation capabilities, which transcodes 64 kilobits / second pulse code modulation to relay the bearer voice channel data to the MSC116. Formatting into (PCM) audio data.

In addition to bearer data, the T-interface also conveys one or more signaling links. For example, the T-interface uses a standard LAPD data link to convey a signaling link for ОAM &amp; P control of transcoding device 115 by base station controller 112. The T-interface also uses one T1 DSO time slot each to carry the SS7 signaling link between the base station controller 112 and the MSC116. The signal system information of these links is transparently relayed between the base station controller 112 and the MSC 116 via the transcoding device 115. The T-interface may also optionally carry a communication link between base station 109 and operations management center (ОMC) 120.

The transcoding device 115 (if provided) is connected to the MSC116 by a standard interface, such as the GSM A-interface. Instead, the functionality of the transcoding device 115 may be incorporated within the base station controller 112, in which case the base station controller 112 connects to the MSC 116 through a standard interface, such as the GSM A-interface. Will be done. The A-interface is shown in Figure 1 and is also shown in Figure 7 with reference number 571. Details of the GSM A-interface are described, for example, in Non-Patent Document 1. Some modifications are preferably made to the standard GSM A-interface to support the features and functions of one or more preferred embodiments described herein. Such changes include, for example, the use of T1 lines as physical interfaces to carry both traffic and signaling, and the use of μ-code coding in certain geographic areas (eg, North America). Is included.

The bearer link connects between the transcoding device 115 and the MSC116, whereas the signaling link for the A-interface generally extends logically between the base station controller 112 and the MSC116. .. The transcoding device 115 processes the 16 kbps bearer link received through the T-interface to generate a 64 kbps pulse code modulated link towards the MSC116, as specifically mentioned. The A-interface signaling channel is a signaling connection control. part: SCCP) Communicates a logical signal system link. An SCCP link is maintained between base station controller 112 and MSC116 for each active CPE trunk (ie, "logical mobile station") of wireless access communicator 106 communicating with PSTN125. The signal system information transmitted through the A-interface is the SS7 signal system between the base station controller 112 and MSC116 for link management, the A-interface radio resource management signal system, the A-interface mobile management signal system, and the radio. It includes a call control signal system relayed by the base station controller 112 between the access communication device 106 and the MSC 116, and optionally an ОAM &amp; P signal system between the base station controller 112 and the ОMC 120. A-interface signaling traffic passes through transcoding apparatus 115 (if provided), and transcoding apparatus 115 signals the signaling between base station controller 112 and MSC116, as described. Transcode information transparently.

As previously mentioned herein, the preferred communication system 101 according to the present invention utilizes both GSM and non-GSM aspects of the signaling system. In a preferred embodiment, GSM signaling and messaging embodiments are used within communication system 101 such that the interconnection of physical protocols is essentially transparent at the network level. In this embodiment, non-GSM physical. Layer) is adopted, while communication with the MSC116 is packaged using the GSM signaling format, resulting in a non-GSM aspect of the wireless system being transparent to the network. The details of the various interfaces used in the preferred system are described above, while the signaling schemes and protocols performed within the communication system 101 are described in more detail below. The signaling schemes and protocols are described with reference to the particular interfaces shown in FIGS. 1, 7 and 10, although aspects of the signaling schemes and protocols may be similarly adopted with other interface configurations. Good.

FIG. 8 shows a protocol architecture for a particular embodiment of the preferred communication system 101, and further includes a wireless access communication device 106, a base station, via О-interface 560, N-interface 562 and A-interface 571. It shows a favorable connection relationship between 109, base station controller 112 and MSC116. In the protocol architecture shown in Figure 8, "CM" is associated with connection management, "MM" is associated with mobility management, "ОTA" is associated with the over-the-air protocol, and " "LAPD" is associated with the link access protocol for the D channel, "IWF" is associated with the interconnect function, "PhL" is associated with the physical layer, and "BSSMAP" is the base station subsystem. Base station subsystem management application Associated with part), "SCCP" associated with SS7 Signaling Connection Control, "MTP" associated with message forwarding (MTP layers 2 and 3), "ОAM" associated with operations, maintenance and management (operations) , Maintenance and administration), "NTS-MM" is associated with N-Note mobility management, and "NTS-RR" is associated with N-Note radio resource management.

For most physical radio functions, a preferred embodiment of the communication system utilizes the protocol architecture for the IS-661 mobile system. For higher level functionality, the preferred embodiment of the communication system uses the GSM aspect, as described in more detail below.

The call control protocol is the call control entity of the GSM direction transfer application part (DTAP) and is shown as the GSM-CM layer in FIG. This GSM The DTAP call control entity (ie, the GSM-CM layer) is (1) establishing, maintaining and releasing a normal outgoing voice call (ie originating from CPE105) between the wireless access communication device 106 and the MSC116. And (2) establishing, maintaining and releasing an emergency (ie, "911") outgoing voice call between the wireless access communication device 106 and the MSC116, and (3) in the direction of the network while the call is active. It supports various functions including the DTMF tone signal system from CPE105. Since the digit analysis is preferably performed at the base station 109, transparent digit transmission is performed between the wireless access communication device 106 and the base station 109. In addition, the system also preferably provides control transport (CT-TRA) О-transport capability for DTAP protocol messages.

GSM shown as GSM-MM layer in Figure 8 The DTAP mobility management entity is used end-to-end (between wireless access communication device 106 and MSC116) to perform various mobility management procedures, including authentication and subscriber identification. Other mobility management procedures are supported on О-interface 560 and N-interface 562 as protocol parts using О-notes and N-notes, and are shown as ОTA-MM and NTS-MM entities in Figure 8. ing. These other mobility management procedures include location updates or network-level registration (both regular and regular), IMSI detachment or deregistration, and temporary mobile subscriber identity (TMSI) re-registration. Includes allocation and establishment of mobile management connections (for both regular and emergency calls). These mobility management procedures are affected by interconnection within base station 109 and base station controller 112, which translates these procedures into corresponding GSM mobility management procedures via A-interface 571. In addition, base station level registration (both regular and regular) between the wireless access communication device 106 and base station 109 is supported by the О-Note movement management procedure.

The GSM-CM and GSM-MM protocols run end-to-end between the wireless access communication device 106 and base station 109, and protocol messages are sent via base station 109 and base station controller 112. , Relayed to transparent. Protocol messages are transported over О-interface 560 О-Note (CT-TRA) messages, transport over N-interface 562 with the LAPD signaling link between base station 109 and base station controller 112. It may be encapsulated within an N-note message and a BSSMAP message on A-interface 571 with an SCCP signaling link.

The radio movement management procedure interconnects within the base station 109 with the N-note movement management procedure shown as the NTS-MM layer in FIG. The NTS-MM procedure is performed on the LAPD signaling link of N-interface 562 and interconnects within the base station controller 112 with the corresponding DTAP mobile management (GSM-MM) procedure on the A-interface. The GSM-MM protocol is therefore partly executed end-to-end between the wireless access communication device 106 and the MSC116, and partly between the base station controller 112 and the MSC116. To.

The radio resource management function is provided by the ОTA Radio Resource (ОTA-RR) management protocol entity shown in Figure 8. Such radio resource management functions include link acquisition, lost link recovery, bearer message encryption, radio slot negotiation and time slot interaction (for TDMA systems), digit transmission and analysis, and assignment. ) And mode change, link release (whether started by network or wireless access communication device 106), base station support information, and surrounding base station table information. On О-Interface 560, radio resource management is performed by the ОTA-RR entity as part of the О-Note protocol.

The О-Note protocol on О-Interface 560 has a link layer function for managing wireless communication channels (ie, wireless communication links). These link layer management features include ARQ, Cyclic Redundancy Check (CRC), segmentation and desegmentation, power control, and more.

The radio resource function component that requires interaction with base station controller 112 and MSC116 is the radio resource function within the N-Note protocol on the N-interface 562, represented by base station 109 as the NTS-RR entity in Figure 8. To be interconnected with. The base station controller 112 then interconnects the radio resource function with the BS SMAP layer function on the A-interface 571. Radio resource management procedures such as channel allocation and channel release are initiated by the MSC116 via BSSMAP procedures, and the base station controller 112 translates these procedures into NTS-RR protocol procedures on N-interface 562.

Through N-interface 562, NTS-RR protocol procedures for radio resource management include encryption, allocation and mode conversion, and link release. In addition to the radio resource function, the function of the NTS-RR entity includes procedures for managing bearer channel allocation and deallocation on one or more backhaul links on N-interface 562.

On the N-interface 562, the signaling link is based on the LAPD protocol. BSSMAP messages are delivered to the SCCP connection through the A-interface. The SCCP and MTP layers are used to provide a robust signaling link between the base station controller 112 and the MSC116.

Various BSSMAP procedures are performed on the A-interface 571 to support the functionality of the wireless access communication device 106. These BSSMAP procedures include, for example, assign, block, reset, release, cipher mode control and initial messages.

The wireless access communication device 106 may be fixedly deployed if desired, so that the mobile function may not be supported. For example, wireless access communication device 106 supports in-call handovers to different base stations, broadcast channels, asymmetric channels, subrate channels, aggregated channels, multiplex mode traffic, signaling message encryption, or wireless D channels. You don't have to. Also, the wireless access communication device 106 does not need to support incoming call paging, SMS call calling, or call-related supplemental services. By eliminating these functions, it is possible to simplify the implementation of the wireless access communication device 106, and also to simplify the support functions required by the base station subsystem and other network-side components. ..

The establishment of a movement management connection for a normal call is initiated by the movement management entity of the wireless access communication device 106 (ie, the GSM-MM entity shown in FIG. 8). To do this, the roaming management entity sends a connection management (CM) service request message to the MSC116 with a service type field indicating that it is a normal call. The MSC116 responds by sending a CM service acceptance message. Upon receiving the CM service acceptance message from the MSC116, the wireless access communication device 106 is a conventional call, as described in detail below and / or in the relevant application incorporated herein by reference. Continue to set up.

For regular calls, the mobility management connection establishment procedure may include an authentication procedure. Such a procedure may be based on the DTAP mobile management signaling scheme for authentication and may be performed end-to-end between the MSC 116 and the wireless access communication device 106.

For emergency calls (ie, "911"), the mobility management entity of wireless access communication device 106 (ie, the GSM-MM entity shown in FIG. 8) has a CM service type field indicating that it is an emergency call. Start the mobility management connection establishment procedure by sending a CM service request message. In response, the MSC 116 sends a CM service acceptance message to the wireless access communication device 106. Upon receiving the CM service acceptance message from the MSC116, the wireless access communication device 106 continues to set up the emergency call. For urgent calls, the network does not need to call the authentication procedure.

If the service request is rejected by the MSC116, or if the service request timeout expires, the wireless access communication device 106 outputs a reorder sound to the CPE105, even if the call establishment procedure is stopped. Good.

The wireless access communication device 106 preferably utilizes the mobile management connection establishment procedure in establishing the call connection, but the CPE trunk is typically not a mobile component of the system. The communication system 101 adapts the techniques used in the mobile communication system to facilitate the setup and maintenance of the wireless trunk 108 through the wireless access communication device 106, as schematically described herein. Using a mobile communication system of a predetermined aspect in a communication system 101 including a wireless access communication device 106 does not require the configuration of a separate base station subsystem or other dedicated radio paths to the PSTN125. In addition, it has the advantage that the infrastructure of the existing mobile communication system can support the wireless trunk according to the present invention.

After the movement management connection establishment procedure is completed, the wireless access communication device 106 exchanges with the MSC116 regarding the DTAP signal method and sets up the outgoing call. The fundamental difference between the procedure for setting up a regular call and the procedure for setting up an emergency call lies in the way the call is initiated. For a normal call, the wireless access communication device 106 sends a DTAP setup message to base station 109 with an empty called address field. Base station 109 writes a pre-stored digit in the called address field of the setup message as part of the digit analysis procedure, and then relays the setup message to MSC116 via base station controller 112. In the case of an emergency call, the wireless access communication device 106 sends a DTAP emergency setup message to the MSC116. The DTAP emergency setup message is transparently relayed through base station 109 and base station controller 112. MSC116 returns a DTAP Call Proceeding message to indicate acceptance of the call request.

If the wireless access communication device 106 receives a DTAP progress message from the MSC116 indicating a PSTN interconnection, the wireless access communication device 106 will have its voice path (eg, wireless communication channel) between the CPE trunk and the wireless communication link. If is a TDMA time slot, connect the wireless time slot). The wireless access communication device 106 then expects a call progress tone to arrive in-band from the network (ie, PSTN125). As the call progresses, the wireless access communication device 106 converts the call progress signal received from the MSC116 into an appropriate sound or signal on the CPE.

If the wireless access communication device 106 receives the DTAP alert message from the MSC116, the wireless access communication device 106 generates a ring tone for the CPE 105. The sound is removed under predetermined conditions including the following (1) to (5). (1) When a DTAP connection message indicating that the called user has answered is received from MSC116. (2) When the call is terminated from the network side by a DTAP disconnection or release completion message. (3) When the call is released using link level (wireless) release. (4) When the timer expires in the wireless access communication device 106. (5) When the wireless access communication device 106 detects the on-hook display signal from the CPE 105.

If the wireless access communication device 106 receives a DTAP disconnection or release completion message indicating that the called party is busy, the operation by the wireless access communication device 106 depends on the presence or absence of PSTN interworking. .. If the wireless access communication device 106 does not receive the PSTN interconnection instruction, the wireless access communication device 106 outputs a busy tone to the CPE 105 and starts the busy tone timer. If the wireless access communication device 106 detects an on-hook display signal from the CPE 105, or if the busy tone timeout period timed by the busy on timer expires, the busy tone is removed by the wireless access communication device 106. .. On the other hand, when a PSTN interconnection exists and a signal indicating that the called person is busy is received, the busy tone is output in-band on the bearer path by the PSTN125, and wireless access communication is performed. It is relayed to CPE105 via device 106.

If the wireless access communication device 106 receives a DTAP connection message from the network indicating that the connection is completed, the wireless access communication device 106 connects the bearer route when it is not connected and sends a DTAP connection acknowledgment message PSTN125. Reply to.

When an exceptional situation occurs during the call establishment, the wireless access communication device 106 cancels the call establishment procedure. Also, for ground-start CPE trunks, it sends a disconnect indication signal to CPE105.

Preferably, call clearing is also supported, which may be initiated at either CPE105 or MSC116. The CPE 105 starts call termination processing by outputting a disconnection signal to the wireless access communication device 106. If the CPE 105 is the caller for the call, the wireless access communication device 106 will start timing the call end processing guard timeout period (eg 600 ms) and when the above period ends, the CPE trunk. Releases, terminates the call using the DTAP signaling scheme, and releases all over-the-air resources.

By transmitting the call end processing message from the network to the wireless access communication device 106, the call end processing is started on the network side (that is, on the MSC116). The response of the wireless access communication device 106 depends on whether the CPE trunk contains a ground-start trunk or a loop-start trunk. If the CPE trunk is a ground-start trunk, when the wireless access communication device 106 receives the call termination processing message from the PSTN125, the wireless access communication device 106 has a call termination processing guard timeout period (that is, 600 milliseconds). ) Is started, and when the period ends, a disconnection instruction is sent to CPE105, and the handset disconnection signal timer is started. The purpose of the handset disconnection signal timer will be described later. The wireless access communication device 106 waits for the disconnection signal from the CPE 105, and after receiving the disconnection signal, stops the handset disconnect timer and releases the CPE and the rank. At the same time, the call termination process for the network is executed and the process is completed, and the radio resource for the call is released.

On the other hand, if the CPE trunk includes a loop start trunk, the wireless access communication device 106 starts the handset disconnect signal timer when the wireless access communication device 106 receives the call end processing message from the PSTN125. The wireless access communication device 106 waits for the disconnection signal from the CPE 105, and after receiving the disconnection signal, stops the handset disconnect timer and releases the CPE trunk. At the same time, the call termination process for the network is executed and the process is completed, and the radio resource for the call is released.

After the network-initiated call termination process, if the user calling through the CPE 105 remains off-hook, a pick-up signal (extended off-hook) condition occurs on the CPE trunk. The wireless access communication device 106 handles this situation by using the above-mentioned handset disconnection signal timer. If the handset disconnection signal timer expires without receiving the disconnect signal from the CPE 105, the wireless access communication device 106 outputs a reorder sound to the CPE 105. If the wireless access communication device 106 has not yet detected a disconnection from the CPE 105 after a predetermined time (for example, 60 seconds) has elapsed since the reorder sound was output in this state, the wireless access communication device 106 removes the reorder sound. It keeps the trunk busy and suspends receiving disconnects from CPE105.

The call progress sound can be summarized as follows. When an off-hook transition is detected on an empty CPE trunk, a dial tone is output from the wireless access communication device 106 to the CPE 105. A busy tone is output when the wireless access communication device 106 receives a DTAP disconnect or release complete message indicating that the called user is busy (for non-PSTN interconnects only). A ring is output when a DTAP Altering message is received (for non-PSTN interconnects only). A reorder sound is output while the wireless access communication device 106 detects a congestion state of wireless access, or when the handset disconnection signal timer expires as described above.

The wireless access communication device 106 may support the transmission of DTMF tones while the call is active. In the "forward" direction, the wireless access communication device 106 detects the DTMF tones generated by the CPE 105 and converts these sounds into a DTAP signaling scheme to the MSC 1165. The MSC116 regenerates DTMF tones to PSTN125 when it receives a DTAP DTMF signaling message. In the "reverse" direction, DTMF tone signaling while such a call is active is generally not supported by current GSM protocols.

The wireless access communication device 106 preferably supports registration of two main types (network level and base station level). For network-level registration and base station-level registration, the wireless access communication device 106 performs two different registrations herein: "normal" registration and "regular" registration. Thereby, in one embodiment of the present invention, four types of registration are supported.

The two types of network level registration supported by wireless access communication device 106 include normal network level registration and periodic network registration. The registration procedure is typically performed by the wireless access communication device 106 instead of the individual CPE trunks, as each of the CPE trunks connected to the wireless access communication device 106 is referenced by the network as an individual subscriber. To. Each CPE trunk is registered separately according to its unique identifier (eg its IMSI). If registration fails for a particular CPE trunk, the wireless access communication device 106 marks the CPE trunk as a failed registration.

When the wireless access communication device 106 is turned on, or when the wireless access communication device 106 changes the location area, that is, it communicates with the base station 109 belonging to a location area different from the previously registered one. At the start, normal network level registration is done. The registration procedure may include the normal location update procedure on A-interface 571.

FIG. 28 is a call flow diagram showing normal network level registration. As shown in FIG. 28, when the power is turned on, the wireless access communication device 106 establishes a wireless communication channel (eg, a wireless time slot in a TDMA system as described above with respect to FIG. 25). After acquiring the wireless communication channel, the wireless access communication device 106 transmits a service request to the base station 109 indicating that a logical link is required for operation and maintenance data on the wireless access communication device 106. The service request can take the form of a control traffic service request (CT-SRQ) message. Base station 109 replies with a control traffic acknowledgment message. The wireless access communication device 106 then sends one or more control traffic forwarding messages containing information about each subscriber identifier (ie, IMSI) of each CPE trunk and the device identifier (ie, IMEI) of the wireless access communication device 106. Send to base station 109. In response, base station 109 inputs the mapping between the IMEI and each IMSI into its device / subscriber table (also referred to herein as its "IMEI table"). Base station 109 then formats the "alarm" message and sends the alarm to OSS 122 with information that identifies the wireless access communication device 106 (ie its IMEI) and a message that the wireless access communication device 106 has been registered. To do. After transmitting the registration information, the wireless access communication device 106 releases the logical link by transmitting a control traffic release (CT-REL) message to the base station 109, as shown in FIG.

In addition to normal network-level registration, the wireless access communication device 106 can also perform periodic network-level registration. To do this, the wireless access communication device 106 periodically re-registers each IMSI (ie, each CPE trunk) after the initial registration at a cycle selected so that the registration interval is less than a predetermined time. .. For example, the predetermined time may be less than the recording retention time of the visitor location register (VLR) in the MSC116. In addition, the predetermined time should be selected so as to be a sufficient length so as not to overload the wireless network. Periodic network-level registration makes a conversion to and from the periodic location update procedure on A-Interface 571. The cycle is configurable in the GSM network infrastructure.

The wireless access communication device 106 also preferably supports two types of base station level registration, ie, normal base station level registration and periodic base station level registration. For base station level registration, each CPE trunk is registered separately by its unique identifier (ie, IMSI).

Normal base station level registration occurs when the wireless access communication device 106 initiates communication with base station 109, which is different from the previously registered one but belongs to the same location area. Normal base station level registration allows the wireless access communication device 106 to receive a new peripheral base station table without having to change the location area. The base station level registration procedure performs a conversion from the normal location update procedure on the A-interface.

The wireless access communication device 106 also performs periodic base station level registration by periodically registering each IMSI (ie, each CPE trunk) with the base station 109. The re-registration cycle is controlled by base station 109. The cycle can be configured by OAM &amp; P, and the re-registration cycle may be selected to be, for example, 16 seconds.

The periodic base station level registration cycle can be used as a mechanism for monitoring the "health status" of the wireless access communication device 106. In this aspect, the periodic base station level registration can act as the "heartbeat" of the base station 109 to know that the wireless access communication device 109 is currently communicating with it.

Deregistration is performed by the system on behalf of each CPE trunk connected to the wireless access communication device 106 when the wireless access communication device 106 is powered off. When the power is turned off, the wireless access communication device 106 initiates a shutdown procedure that includes unregistering each CPE trunk before actually powering it down.

If a failure is detected in the wireless access communication device 106, an alarm message is sent to inform the operator about the failure. When a failure is detected, the wireless access communication device 106 sends a failure notification (ie, an alarm message) to the base station 109 using a control traffic forwarding (CT-TRA) message. Base station 109 then sends a failure report to base station controller 112, which uses the base station object as a faulty entity.

FIG. 29 is a call flow diagram showing the alarm reporting process. As shown in FIG. 29, first a radio communication channel (eg, a time slot in a TDMA system as described above with respect to FIG. 25) is acquired when such a channel has not yet been established. Next, a service request indicating that a logical link is required for operation and maintenance data relating to the wireless access communication device 106 is transmitted from the wireless access communication device 106 to the base station 109. The service request takes the form of a control traffic service request (CT-SRQ) message. After receiving the control traffic acknowledgment message from the base station 109, the wireless access communication device 106 can freely transmit the alarm information to the base station 109. Alarm information may be transmitted in more than one physical message as needed. After transmitting the alarm information, the wireless access communication device 106 releases the logical link by transmitting a control traffic release (CT-REL) message. Base station 109 then packages the alarm information in the format of a base station alarm message and sends it to the Operations Management Center (OMC) 120 and / or OSS 122.

The format of the alarm message or alarm information sent by the wireless access communication device 106 to base station 109 can include multiple fields, such as an identifier field, a failure type field, a status field, a failure cause field, and a log number. Includes fields. The identifier field contains information that identifies the wireless access communication device 106, such as the International Mobile Equipment Identity (IMEI) number. The failure type field contains information indicating the type of failure that has occurred, such as a communication failure, service quality failure, processing failure, or device failure. The status field indicates whether the wireless access communication device 106 is operating or inactive. The failure cause field indicates the cause of the failure, for example, a wireless device failure, a line card failure, or an unknown failure. The log number is used to track the alarm. The wireless access communication device 106 may keep a log of triggered alarms, each with a corresponding log number. The alarm information recorded as a log may be used for debugging later.

If the failure relates to a resource (ie, hardware or software) of the wireless access communication device 106, the alarm report preferably identifies the failed resource if it is identifiable. A failure table may be maintained in the control unit of the wireless access communication device 106 to enable alarm tracking. When an alarm is reported, an entry is made in the fault table. The fault table helps prevent the same alarm from being reported again. The fault table may be cleared at power on or reset.

The base station 109 relays the alarm generated in the wireless access communication device 106 to the base station controller 112 by using the base station alarm message format. The base station alarm message format can include multiple fields, such as a failure type field, a failure level field, a failure cause field, and an additional information field. The fault type field contains information indicating the type of fault (for example, equipment failure), the fault level field indicates the severity of the fault (such as a warning), and the fault cause field (such as wireless access communication device 106). The additional information field, which indicates the cause of the failure, usually contains detailed information about the failure and, in special cases, includes a copy of the alarm message received from the wireless access communication device 106. ..

According to a preferred embodiment of the invention, as shown in FIG. 1, the wireless access communication device 106 establishes a normal outgoing voice call via a GSM-based segment, which provides connectivity to the long-distance function of the PSTN 125. Provides the ability to maintain and disconnect. The wireless access communication device 106 and other system components support standard signaling functions on the CPE interface, including trunk supervision signaling, address signaling, and delivery of call progress to the CPE 105. Provides wired line transparent operation for CPE105.

As part of the initialization procedure after power-on, preferably periodically thereafter, the wireless access communication device 106 registers with nearby base stations 109 and PSTN125. Here, registration is generally described as a process used when a subscriber (ie, CPE trunk 602) connected to the wireless access communication device 106 presents its own identification information to the network. Since each CPE trunk connected to the wireless access communication device 106 is considered by the network as an individual subscriber, the registration procedure is typically performed on behalf of the individual CPE trunk and also multiple. It may need to be repeated for the CPE trunk.

FIG. 12 is a call flow diagram showing the network level registration procedure. As a first step in the procedure shown in FIG. 12, the wireless access communication device 106 may include a wireless communication channel to a nearby base station 109 (eg, a time slot in a TDMA or TDD system, or a frequency channel in an FDD system, or the like. (Regulated channel) is acquired. Wireless communication channels are acquired by specific protocols used by wireless systems. The wireless access communication device 106 then performs a network level registration procedure according to the particular registration protocol used by the system. The registration procedure can also include, for example, a location update procedure on the A-interface 571. The wireless access communication device 106 uses a cycle controlled by the network infrastructure to perform subsequent network-level registration processing at regular intervals. Further, even when the wireless access communication device 106 starts communication via the base station 109 in a location area different from that of the base station with which the communication was previously performed, the wireless access communication device 106 may perform the network level registration process. Good. After registration, the wireless communication channel is surrendered and the MSC116 initiates the resource release procedure as shown in FIG.

In addition to the network-level registration process, the wireless access communication device 106 can also periodically register the base station 109 at regular intervals using the cycle controlled by the base station 109. For each registration attempt, the wireless access communication device 106 acquires and registers the wireless communication channel and surrenders the wireless communication channel unless the call is in progress. If the call is in progress, the wireless access communication device 106 does not need to acquire a new channel, but if possible under a particular wireless protocol, it may transmit registration information across existing communication channels. Can be done. In addition to regular base station level registration, the wireless access communication device 106 is a base station that is different from the base station that was previously communicating, but initiates communication through a base station within the same location area. Also performs the initial registration of base station 109.

When the wireless access communication device 106 is powered off, the system unregisters it on behalf of each CPE trunk connected to the wireless access communication device 106. FIG. 13 is a call flow diagram showing the network level deregistration procedure. As a first step in the procedure shown in FIG. 13, the radio access communication device 106 acquires a radio communication channel (eg, a TDMA time slot) to a nearby base station 109. Wireless communication channels are acquired by the specific RF protocol utilized by the wireless system. The wireless access communication device 106 then performs network-level deregistration procedures, such as the IMSI detach procedure, according to a particular protocol used by the system. After deregistration, the wireless communication channel is surrendered and the MSC116 initiates the resource release procedure, as shown in FIG.

After the registration process by the wireless access communication device 106, an outgoing call to the PSTN 125 may be made via the CPE105, the wireless access communication device 106, and the base station subsystem. Figures 14-19 show a dial tone, digit transmission, digit analysis and call setup for outgoing calls in various types of CPE embodiments, including PBXs and KTXs with different levels of intelligent routing capabilities. It is a figure. For example, Figure 14 shows a dial tone, digit transmission and digit analysis for a "dumb" PBX, that is, a CPE 105 implemented as a PBX that is incapable of routing calls based on the analysis of dialed numbers. It is a flow chart of the call shown. As shown in FIG. 14, user 102 (eg, a telephone station device as shown in FIG. 1) goes off-hook and sends an off-hook signal to the CPE105 (ie, PBX). Upon detecting the off-hook signal, the PBX 105 outputs a dial tone to the user 102. The user 102 then dials an access code (ie, a predetermined digit, eg, "8") to access the wireless trunk provided by the wireless access communication device 106. Upon detecting the digit of the access code, the PBX 105 removes the dial tone and captures the trunk connected to the wireless access communication device 106.

Upon detecting the capture of the trunk, the wireless access communication device 106 outputs a second dial tone to the user 102. The second dial tone is supplied to the user 102 through the PBX 105. In parallel with the application of the second dial tone, the wireless access communication device 106 starts acquiring a wireless communication channel. In TDMA or TDD systems, for example, this step in the procedure generally involves the acquisition of radio time slots.

Upon detecting the dial tone, user 102 begins dialing the called party's number (digit). The wireless access communication device 106 removes the second dial tone after detecting the first digit. If the acquisition of the wireless communication channel has not been completed at this point, the wireless access communication device 106 stores the received digit in a temporary buffer.

After successfully acquiring the radio communication channel, the radio access communication device 106 sends a control traffic service request (CT-SQR) message to the base station 109 for digit analysis at that base station, as shown in FIG. Request service from the application. Base station 109 initiates a digit analysis application and returns a control traffic acknowledgment (CT-ACK) message to wireless access communication device 106. The wireless access communication device 106 then transmits the digits received from the user 102 to the base station 109 one by one each time it is received. Each digit is sent as part of a Control Traffic Forwarding (CT-TRA) message. The value of each digit may be indicated, for example, by a 4-bit field in the CT-TRA message. Base station 109 stores each received digit. When all address digits have been received by base station 109, base station 109 detects that the dial sequence is complete (by digit analysis) and transfers control traffic with a message content indicating that the dial is complete. (CT-TRA) The message is returned to the central call processing device 106. The wireless access communication device 106 can then proceed to make a call.

FIG. 15 is similar to FIG. 14, but here it relates to a "dumb" KTS, the CPE 105 implemented as a simple exchange system that does not have the ability to route calls based on the analysis of dialed numbers. , Dial tone, digit transmission and digit analysis are shown. As shown in FIG. 15, the user 102 first selects the outgoing line to the wireless access communication device 106. User 102 then goes off-hook and sends an off-hook signal to CPE105 (ie KTS). Upon detecting the off-hook signal, the CPE 105 captures the trunk connected to the wireless access communication device 106. When the wireless access communication device 106 detects the capture of the trunk, the wireless access communication device 106 responds to the detection and outputs a dial tone to the user 102. In parallel with the application of the dial tone, the wireless access communication device 106 proceeds to acquire the wireless communication channel. In TDMA or TDD systems, this step generally involves capturing radio time slots.

When the user 102 detects the dial tone 102, it begins dialing the called party's digit (number). After detecting the first digit, the wireless access communication device 106 removes the dial tone. If the acquisition of the wireless communication channel has not been completed by this point, the wireless access communication device 106 stores the digit in the temporary buffer.

When the wireless communication channel is successfully acquired, the wireless access communication device 106 sends a control traffic service request (CT-SRQ) message to the base station 109 to the digit analysis application in the base station 109, as shown in FIG. Request service. Base station 109 initiates a digit analysis application and returns a control traffic acknowledgment (CT-ACK) message to wireless access communication device 106. The wireless access communication device 106 then transmits the digits received from the user to the base station 109 one by one each time it is received. Each digit is sent as part of a Control Traffic Forwarding (CT-TRA) message, as described with respect to FIG. Base station 109 stores each received digit. After all address digits have been received by base station 109, base station 109 detects that the dial sequence is complete (based on its digit analysis), and control traffic with message content indicating that dialing is complete. The forwarding (CT-TRA) message is returned to the central call processor 106.

FIG. 16 shows dial tone, digit transmission and digit analysis similar to FIGS. 14 and 15, but here it is sufficiently built-in intelligent to route calls based on the analysis of dialed numbers. The CPE105 implemented as a functional PBX system is shown. As shown in FIG. 16, user 102 first offhooks and sends an offhook signal to the CPE105 (ie PBX). Upon detecting the off-hook signal, the CPE 105 outputs a dial tone to the user 102. User 102 then dials an access code (ie a predetermined digit such as "8" or "9") to access the outside line. Upon detecting the digit of the access code, CPE105 removes the dial tone and initiates digit analysis. When it is detected that the dialed number is a digit of a predetermined access code, the CPE 105 outputs a second dial tone to the user 102.

User 102 then begins dialing the called party's digit (number). Upon detecting the first digit from user 102, CPE105 removes the dial tone and initiates digit analysis. When the CPE105 receives all the digits, the CPE105 determines from the digit analysis that the full phone number has been dialed. CPE105 also determines from its digit analysis whether the call is long-distance (ie, the first digit called after the access code is "1"), and if the call is long-distance. When capturing the trunk connected to the wireless access communication device 106. When the call is not long-range, CPE105 routes the call directly to PSTN125.

Upon detecting the capture of the CPE trunk, the wireless access communication device 106 outputs a second dial tone to the user. This second dial tone is muted by the user's CPE105, that is, the second dial tone is not sent to the user 102. In parallel with the application of the second dial tone, the wireless access communication device 106 proceeds to acquire a wireless communication channel. For example, in a TDMA or TDD system, for example, this step generally involves capturing a radio time slot. When the second dial tone is detected by the CPE 105, the CPE 105 begins to output the previously received digit from the user 102 as a DTMF tone to the wireless access communication device 106. Upon detecting the first digit (ie, the DTMF tone), the wireless access communication device 106 removes the second dial tone. If the acquisition of the wireless communication channel has not been completed by this point, the wireless access communication device 106 stores the digit in a temporary buffer until the wireless communication channel is available.

After successfully acquiring the radio communication channel, the radio access communication device 106 sends a control traffic service request (CT-SRQ) message to base station 109 and requests service from the digit analysis application at base station 109. Base station 109 initiates a digit analysis application and returns a control traffic acknowledgment (CT-ACK) message to wireless access communication device 106. The wireless access communication device 106 then transmits the digits received from the user to the base station 109 one by one each time it is received. Each digit is sent as part of a Control Traffic Forwarding (CT-TRA) message. Base station 109 stores each received digit. After all address digits have been received by base station 109, base station 109 detects that the dial sequence is complete and a control traffic forwarding (CT-TRA) message containing message content indicating that dialing is complete. Is returned to the central call processing device 106. The wireless access communication device 106 can then proceed to make a call.

FIG. 17 is similar to FIGS. 14, 15 and 16 but here is a simple exchange system with sufficient built-in intelligent functionality to route calls based on the analysis of dialed numbers. The dial tone, digit transmission and digit analysis related to CPE105 implemented as KTS) are shown. As shown in FIG. 17, user 102 first off-hooks and sends an off-hook signal to CPE105 (ie KTS). Upon detecting the off-hook signal, the CPE 105 outputs a dial tone to the user 102. User 102 then dials the called person's digit (number). Upon detecting the first digit from the user, CPE105 removes the dial tone and initiates digit analysis.

After the CPE105 has received all the digits, the CPE105 determines from its digit analysis that the full phone number has been dialed. The CPE105 also determines from its digit analysis whether the call is long-range (ie, the first digit dialed is "1"), and if the call is long-range, radio. Capture the trunk connected to the access communication device 106. If the call is not long-range, CPE105 routes the call directly to PSTN125.

When the trunk is captured, the wireless access communication device 106 outputs a second dial tone to the CPE 105. This second dial tone is muted by the user's CPE105, that is, the second dial tone is not sent to the user. In parallel with the application of the second dial tone, the wireless access communication device 106 proceeds to acquire a wireless communication channel. In TDMA or TDD systems, this step generally involves capturing radio time slots. When the second dial tone is detected by the CPE 105, the CPE 105 outputs the previously received digit from the user 102 to the wireless access communication device 106. Upon detecting the first digit, the wireless access communication device 106 removes the second dial tone. If the acquisition of the wireless communication channel has not been completed by this point, the wireless access communication device 106 stores the digit in a temporary buffer.

After successfully acquiring the radio communication channel, the radio access communication device 106 sends a control traffic service request (CT-SRQ) message to base station 109 and requests service from the digit analysis application at base station 109. Base station 109 initiates a digit analysis application and returns a control traffic acknowledgment (CT-ACK) message to wireless access communication device 106. The wireless access communication device 106 then transmits the digits received from the user to the base station 109 one by one each time it is received. Each digit is sent as part of a Control Traffic Forwarding (CT-TRA) message. Base station 109 stores each received digit. After all address digits have been received by base station 109, base station 109 detects that the dial sequence is complete and has a control traffic forwarding (CT-TRA) message with message content indicating that the dial is complete. Is returned to the central call processing device 106. The wireless access communication device 106 can then proceed to make a call.

If the wireless access communication device 106 outputs a dial tone (or a second dial tone) and has not received a digit from the CPE 105 within a preset time, it is a dial timeout condition. In that case, the wireless access communication device 106 releases all radio communication channels that may have been captured and takes action for the unreceived state for the user (that is, performs the deregistration procedure if necessary). Let MSC116 release all resources allocated for the call).

18 and 19 are call flow diagrams showing successful call setup procedures in two scenarios. FIG. 18 is a call flow diagram of a successful normal (ie, non-urgent) call setup sequence initiated from the CPE without PSTN interconnection on the MSC116. As shown in FIG. 18, dial tone supply, digit transmission and digit analysis are performed according to one of the scenarios shown in the call flow diagram of FIGS. 14-17. In each example, the call flow ends when the dial display signal from the base station 109 to the wireless access communication device 106 ends. Upon receiving the end of the dial display signal from the base station 109, the wireless access communication device 106 starts the procedure for establishing a mobile management connection for a normal call. As a result of this procedure, an SCCP link is established for calls over A-interface 571 (assuming it is a GSM system), and in addition, a roaming management connection to MSC116 is set up to handle the calls. Will be done. Part of this procedure may be accompanied by authentication and cipher mode setting procedures for the call, if desired.

After completing the mobile management connection procedure, the wireless access communication device 106 sends a direct transfer application (DTAP) setup message to base station 109, as shown in FIG. The DTAP setup message contains an empty called address field and is sent to MSC116. Base station 109 receives its DTAP setup message in the middle and writes in the called address field the digits received from the wireless access communication device 106 during the previous digit analysis step. Base station 109 then forwards the DTAP message to MSC116 through the base station controller. The MSC116 acknowledges the DTAP setup message by sending a DTAP call in progress message to the wireless access communication device 106, as shown in FIG.

The bearer resource allocation procedure is then performed at each interface of the wireless fixed access system starting at A-interface 571 and proceeding to O-interface 560. As a result of the bearer resource allocation procedure, bearer channels are assigned to A-interface 571, N-interface 562, and O-interface 560, and exchanged connections are set up via base station controller 112.

After completing the bearer resource allocation procedure, the MSC116 sends a DTAP alert message to the wireless access communication device 106. The wireless access communication device 106 sends a ringing tone to the user 102 via an in-band path through the CPE 105 (ie, PBX or KTS, or other similar system). When the called party answers the call, the MSC116 sends a DTAP connection message to the wireless access communication device 106. At that point, the wireless access communication device 106 is attached to the voice path and removes the ringing tone to the user. The wireless access communication device 106 responds to the MSC116 with a DTAP connection acknowledgment message, at which time the call is in a conversational state.

FIG. 19 shows the call flow when the normal call setup sequence started from the CPE is successful, as in FIG. 18, but the MSC116 has PSTN interconnection. As shown in FIG. 19, dial tone supply, digit transmission and digit analysis are performed according to any scenario shown in the call flow diagrams of FIGS. 14-17. Upon receiving the end of the dial display signal from the base station 109, the wireless access communication device 106 starts the mobile management connection establishment procedure for a normal call. Similar to the call flow in Figure 18, as a result of this procedure, an SCCP link is established for calls over the A-interface (assuming it is a GSM system), and further processes the call. A roaming management connection to MSC116 is set up for this. If desired, part of this procedure may involve authentication and cipher mode of operation for the call.

After the mobile management connection procedure is completed, the wireless access communication device 106 sends a DTAP setup message to the base station 109. The DTAP setup message contains an empty called address field and is sent to MSC116. Base station 109 receives the DTAP setup message in the middle and writes the digit received from the wireless access communication device in the previous digit analysis step into the address field. The base station 109 then transmits a DTAP setup message to the MSC116 via the base station controller 112. The MSC116 acknowledges the receipt of the DTAP setup message by sending a DTAP call in progress message to the wireless access communication device 106, as shown in FIG. The bearer resource allocation procedure is then performed at each interface of the wireless fixed access system starting at the A-interface and proceeding to the O-interface, similar to the call flow in FIG. As a result of the bearer resource allocation procedure, bearer channels are assigned to the A-interface, N-interface, and O-interface, and the exchanged connection is set up via the base station controller 112.

After completing the bearer resource allocation procedure, the MSC116 sends a DTAP progress message indicating the interconnection with the PSTN125 to the wireless access communication device 106. The wireless access communication device 106 is attached to the voice path at this point. The network detects a ringing tone on the connected voice path, and the ringing tone is delivered to the user 102 via the CPE105 (ie, KTS or PBX, or other similar system) by the wireless access communication device 106. It is relayed and transmitted. When the called person answers the call, the network removes the ring. The MSC116 sends a DTAP connection message to the wireless access communication device 106. The wireless access communication device 106 responds with a DTAP connection acknowledgment message, after which the call transitions to the conversational state.

In either call flow scenario shown in FIG. 18 or FIG. 19, this call is generally rejected if the called person is busy. If the PSTN interconnect is not made, the wireless access communication device 106 sends a busy tone to the user 102 in response to the DTAP disconnection message from the MSC116, and the DTAP release procedure is started. When the on-hook signal is detected by the user 102, the wireless access communication device 106 starts the call resource release procedure. When making a PSTN interconnect, the busy tone is transmitted from the PSTN125. When the CPE 105 detects an on-hook signal from user 102, it sends a disconnect message to wireless access communicator 106, which initiates the DTAP release procedure, followed by the call resource release procedure.

When ISDN interconnections are made over a long-distance network interface, the wireless access communication device 106 produces an appropriate call progress to the CPE 105 based on the DTAP signaling scheme received from the MSC116. Such ring tones include, for example, busy tones and ring tones. When making PSTN interconnects, these call transitions are generated by the PSTN125 and sent in-band to the wireless access communication device 106, which relays them to the CPE 105. The dial tone is always generated by the wireless access communication device 106. Further, the reorder sound may be generated by the wireless access communication device 106 in a congested state or as a part of the handset disconnection process.

20 to 22 are call flow diagrams showing various call scenarios. FIG. 20 shows the call flow for the status of incoming calls during a call while the call is active. As shown in FIG. 20, the first user is busy about an active call on the network. The second user wants the first user to call and generate an off-hook signal. The CPE105 (ie, KTS, PBX or other similar system) detects an off-hook signal and responds with a dial tone. The second user dials the first user's phone number, but since this call is not long-distance (rather inter-station), it is processed by the CPE105 itself, after which it is wirelessly accessed. It transmits to the communication device 106. Upon detecting the first digit from the second user, the CPE 105 removes the dial tone.

After the number is dialed, the CPE 105 attempts to propagate the call to the first user. If the first user knows that another call is already busy, the CPE105 outputs a call waiting tone to the first user, and the other caller attempts to connect. Notify the first user that you are. CPE105 also outputs a ringing tone to the second user, notifying that the first user is being called.

If the first user answers the in-call ringtone with a hook flash, the CPE105 detects the hook flash signal and puts the first conversation on hold. The CPE105 then connects the first user and the second user to the conversation. The first user can then switch between conversations by using the hook flash signal, as shown in FIG.

FIG. 21 is a call flow diagram showing a three-party call setup scenario. At the beginning of the call flow shown in Figure 21, assume that the first user is already busy with an active call on the network. The first user then decides to make an inter-station call to the second user. To do so, the first user supplies the CPE 105 with a hook flash signal. The CPE105 responds by giving a recall dial tone to the first user and putting the original conversation on hold. The first user then dials the extension of the second user. When CPE105 detects the first digit of the dialed extension, it ends the recall dial tone.

After the extension dialing is complete, CPE105 attempts to send a call to a second user. At the same time, the CPE 105 supplies a ringing tone to the first user. When the CPE105 receives an off-hook signal from the second user, it ends the ring to the first user. The first user and the second user can then have a conversation in an active call. Upon detecting the hook flash signal from the first user, the CPE 105 connects the two calls and completes a three-way call.

In each of the call flow situations of FIGS. 20 and 21, the call function is transparently provided to the end user. In addition, calls are achieved transparently on PSTN125 as well.

FIG. 22 shows the DTMF signaling procedure while the call from CPE105 to PSTN125 is active. Upon detecting a DTMF tone from the CPE 105 that exceeds the preset minimum DTMF timeout period (eg, 20 ms), the wireless access communication device 106 sends a DTAP start DTMF message to the MSC116. The DTAP start DTMF message indicates that a digit is being sent. When the MSC116 receives this message, it regenerates the DTMF tone towards the network and sends a DTAP start DTMF acknowledgment message back to the wireless access communicator 106.

When the wireless access communication device 106 detects a DTAP start DTMF acknowledgment message, it sends a DTAP stop DTMF message to the MSC116. Upon receiving the DTAP stop DTMF message, the MSC116 stops sending DTMF tones to the network. The MSC116 returns a DTAP stop DTMF acknowledgment message to the wireless access communication device 106. This procedure is repeated for each DTMF tone transmitted by CPE105.

Both the DTAP start DTMF message and the DTAP stop DTMF message are messages supported by the existing GSM protocol. The wireless access communication device 106 uses the DTAP start DTMF message and the DTAP stop DTMF message to transparently transmit information related to the DTMF tone to the base station 109 and the base station controller 112 while the call is active. This causes the DTMF tones to be associated across the radio communication channels and regenerated by the MSC116 before being relayed over the network.

Both regular and emergency calls can be handled by the preferred communication system 101 of FIG. Emergency calls (ie, "911" calls) are preferably routed directly to PSTN125 by CPE105. This may be achieved in the same way that other calls are routed. For example, the user may dial the PSTN access code for an emergency call (for PBX) or select the PSTN trunk from the desk phone (for KTS). Alternatively, the CPE105 can be configured to route emergency calls to the PSTN trunk by analyzing the received digits. Nevertheless, it may be desirable to give the wireless access communication device 106 the ability to establish, maintain, and disconnect an emergency call when it receives a trigger to make such a call. The wireless access communication device 106 may use GSM-based segments to perform these emergency call operations.

23 and 24 are frequency distribution diagrams showing the respective spectral allocations for radio resources in the two specific embodiments of the present invention. FIG. 23 shows possible spectral allocation over the available radio frequency bandwidth of 5 MHz. As shown in FIG. 23, the 5 MHz bandwidth may be divided into three sub-bands, each with a center frequency at 1.6 MHz intervals, from the center frequency of each outer sub-band to 5 MHz. The interval to the outer edge of the bandwidth is 0.9MHz. FIG. 24 shows possible spectral allocations over the available radio frequency bandwidth of 6.6 MHz. As shown in FIG. 24, the 6.6 MHz bandwidth may be divided into four sub-bands, each with a center frequency at 1.6 MHz intervals, from the center frequency of each outer sub-band. The interval is 0.9MHz up to the outer edge of the 6.6MHz bandwidth. Also in such an embodiment of FIG. 23 and FIG. 24, the radio transmitter (either of the base station 109 and the wireless access communication device 106) has a signal, preferably with a maximum bandwidth of approximately 1.6 MHz. , Directly transmit the diffusion spectrum diffusion signal. The specific spectral allocations in FIGS. 23 and 24 are merely exemplary and represent possible spectral allocations for preferred spectral diffusion radio communication paths. However, any spectral allocation can be used for the purpose of the particular wireless connection used between the base station 109 and the wireless access communication device 106.

One or more embodiments are described above according to various aspects of the invention, but many variations of these embodiments are the same or similar operating principles as described herein. Exists while incorporating. For example, it will be apparent to those skilled in the art that the functions of the CPE 105 and the wireless access communication device 106 can be combined within a single device. It is also possible for one or more telephone station devices 102 to bypass the CPE 105 and be directly connected to the wireless access communication device 106. Further, the CPE 105 does not need to be connected to the telephone station device 102 by a telephone line and may be wirelessly connected to it (ie, wireless PBX).

Local area communication systems according to certain aspects of the invention are relatively easy to deploy in remote and / or rural areas, as opposed to systems that require a land line connection from a PBX or KTS to a network. Let's go. In addition to connecting wireless access communication devices to PBXs or KTSs, remote local area communication systems benefit from wireless networks (including long-distance access) with the addition of relatively little deployment effort. Can receive.

Although preferred embodiments of the present invention have been described herein, many variations are possible within the scope and concepts of the present invention. Such variations will be apparent to those skilled in the art with reference to the specification and drawings. The present invention is therefore not limited in any way except by the spirit and scope of the appended claims.