Wireless telecommunications system utilizing cdma radio frequency signal modulation in conjunction with the gsm a-interface telecommunications network protocol.

(74) Agent: MILLER, Russell, B. et al .; Qualcomm Join *). 6455 Lusk Boulevard, San Diego, CA 92121 (US).

(81) Designated States: AL, AM, AT, AU, AZ, BA, BB, BG_r BR. BY, CA, CH, CN, CU, CZ, DE. DK, EE, ES, FI, GB, GE, HU, IL, IS, JP. KE, KG, KP, KR, KZ, LC, LK, LR, LS. LT, LU, LV, MD. MG, MK, MN. MW, MX. NO, NZ, PL, PT, RO, RU. SD. I KNOW. SG, SI, SK, TI, TM, TR, IT, UA, UG, UZ, VN, ARITO patem (KE, LS, MW, SD, SZ. UG), Eurasian patent (AM, AZ, BY, KG, KZ , MD. RU, TI, TM), European patent (AT, BE. CH, DE. DK, ES, FI. FR. GB, GR. IE, IT, LU, MC, NL, PT. SE), OAPI patent (BF, BJ, CF, CG, C], CM, GA, GN. ML. MR, NE, SN, TD, TG).

Publishcd

Without internatúmaí search repon and ¡o be republishetl upan receipi of ihai repon.

(54) Title: WIRELESS TELECOMMUNICAT1ONS SYSTEM UTIUZ1NG COMA RADÍO FREQUENCY SIGNAL MODULATION IN CONJUNCTTON WITH THE GSM A-INTERFACE TELECOMMUN1CATIONS NETWORK PROTOCOL

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(37) Abetract

A method and apparatus for operating a wireless telecommumcation system utilizing code multiple division access (CDMA) over-theair with a Global System for Motile (GSM) communications A-interface based network is described. A CDMA radio ftequeney (RF) signa! interface provides a bi-directional interface to a subscriber unít (50). and a Global System for Mobile (GSM) communications A-interfacc SS7 transpon provides a bi-directianal Interface with GSM mobile servio »switching centcr (MSC) (52). Additionally, a transparent message transpon (44) is provided over whlch slgnaling messages defined in the GSM A-mterface protocol are exchanged between the GSM MSC (52) and a subscriber unit (50).

-1WIRELESS TELECOMMUNICATION SYSTEM

THAT USES RADIO FREQUENCY MODULATION

CDMA IN CONJUNCTION WITH THE GSM INTERFACE A TELECOMMUNICATION NETWORK PROTOCOL

FIELD OF THE INVENTION

The present invention relates to wireless telecommunications. More particularly, the present invention relates to a novel and improved method and apparatus for providing wireless telecommunication service using a Code Division Multiple Access (CDMA) on-air interface in conjunction with an interface protocol A interface. of the Global System for Mobile Communications (GSM).

BACKGROUND OF THE INVENTION

The Global System for Mobile Communications (GSM) wireless telecommunications standard is a set of digital protocols that are widely available for use within a digital wireless telephone system. The GSM specifications were developed through an international effort and have been adopted by the European Telecommunications Standards Institute ETSI, 06921 Sophia Antipolis Cedex, France. A P1412 / 98MX

-2i wireless telephone system configured in a manner consistent with the use of GSM standards is shown in Figure 1. The GSM mobile service switching center (MSC) 16 switches or connects telephone calls between the system's access network wireless, namely, the base station subsystems (BSS) 15 and the wired base public switched telephone network (PSTN) 18, which may also be a public land mobile network (PLMN). GSM-MSC 16 provides telephone switching, billing, subscriber unit tracking, authorization to the subscriber unit and some transfer control functionalities. The BSS 15 consist of the base station controller (BSC) 14 and any transceiver stations (BTS) 12 coupled to it. As defined in the GSM specifications, the interface between GSM-MSC 16 and BSS 15 is referred to as the GSM interface A, which separates the GSM network switching equipment from multiple access radio equipment. by time division (TDMA). BSC 14 is involved in allocating transfer processing and signal processing resource within BTS 12 so that multiple subscriber units 10 can conduct phone calls simultaneously. BTS 12 interfaces with subscriber units 10 via radio signals

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-3i frequency (RF) and a well-defined protocol over the air with the GSM wireless network. The BTS 12 comprises radio transmission and reception devices, up to and including antenna devices and also all the specific signal processing for the radio interface. BTS can be considered as complex radio modems. Subscriber unit 10 provides generic radio and processing functions for access to the GSM network through the radio interface to either the user of subscriber unit 10 or some other terminal equipment, such as a machine. fax or personal computer. A particular subscriber unit 10 can switch to the BTS 12 it interfaces with as its location changes but can only communicate with a BTS at any given time. Within this application, the ability to switch from one BTS 10 to another BTS 10, where only one radio interface exists at any one time, is referred to as the hard transfer of the subscriber unit.

In order to make a wireless phone call, a network connection must be established between the subscriber unit 10, often referred to as the mobile unit and PSTN 18. PSTN 18 is the conventional wired telephone system. To conduct the phone call in a mobile way, a portion of the network connection is formed

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-4X by exchanging radio frequency (RF) signals between subscriber unit 10 and BTS 12. The rest of the portion of the network connection is normally formed through wired base connections that pass through BSS 15 and through GSM-MSC 16. In accordance with the GSM over-the-air protocol, ”which is one of the protocols that make up the GSM wireless telecommunications standard, TDMA technology is used to establish a set of channels within the aforementioned RF signals used to interconnect. to a subscriber unit 10 with a BTS 12. These channels are used to separate and distinguish the various data sets associated with the various phone calls that are made at any given time. The various data sets include user data that normally takes the form of digitized audio information and signaling data that are comprised of the signaling messages used to orchestrate the processing of a telephone call.

At the time of the start of the GSM standard, the use of TDMA within the GSM over-the-air protocol increased the efficiency with which the given radio frequency bandwidth could be used to conduct wireless phone calls. Increased efficiency with which the P1412 / 98MX bandwidth is used

-5i available radio frequency is desirable, because only a limited amount of RF bandwidth exists and the amount or amount of bandwidth is normally the limiting factor for the number of calls that can be conducted by a system private wireless cell phone. However, due to the inception or start of the GSM wireless telecommunications protocol, other wireless technologies have been perfected that allow a greater number of telephone calls to be conducted over a given RF bandwidth. Since the efficient use of radio frequency bandwidth is highly desirable, the use of these more efficient technologies is currently preferred.

A prominent and widely accepted example of more efficient wireless telecommunications technology is signal processing using Code Division Multiple Access (CDMA) and the associated IS-95 over-the-air protocol, adopted by the Telecommunications International Association (TIA, 2001 Pennsylvania Avenue, NW, Washington, DC 20006). With CDMA modulation techniques, each user traffic channel consists of a carrier modulated by a different high-speed binary sequence, thereby dispersing the spectrum of the waveform. The Ρ1412 / 9ΘΜΧ sets of user traffic channels share the same broadband frequency spectrum allocation and both the user data and signaling messages are transmitted over the user traffic channel. Additionally, each CDMA base mite transmits air traffic control signaling channels that carry information to allow the subscriber unit to acquire and access the system. These air traffic control channels are also modulated with a high speed bit stream and combined with the user traffic channels to comprise a broadband RF signal. Each CDMA-based BTS transmits the combined RF signal, referred to as the broadcast CDMA channel, and receives the combined RF outputs from a set of CDMA-based subscriber units, located within an associated coverage area, where this combined set of outputs is referred to as the reverse CDMA channel. The direct CDMA channel is the sum of the direct pilot channel, the direct synchronization channel, one or more direct radio location channels, and many direct user traffic channels that are each modulated with a different channel code and combined with a PN scattering sequence. The CDMA channel is the sum of one or more reverse access channels and many reverse user traffic channels that are each P1412 / 98MX modulated with a unique channel code and transmitted with a specific PN spreading sequence.

CDMA-based wireless communication systems also offer an improved transfer method for mobility of the subscriber unit. A handover procedure known as soft handover is provided by the ability to use the RF signals from the subscriber unit in more than one CDMA-based BTS. This smooth transfer ability of the subscriber unit 10 to simultaneously couple on multiple RF interfaces with multiple CDMA-based BTS 12s, provides redundancy of the transmission path as the subscriber unit 10 moves from one location to another, decreasing from this This provides opportunities for a call to be interrupted and voice samples to be lost. Additionally, the IS-95 protocol provides a superior quality telecommunications service when compared to GSM, since the CDMA signal is less susceptible to fading and noise interference. A subscriber unit that communicates in accordance with the IS-95 protocol also consumes less energy than a subscriber unit that communicates in accordance with the GSM over-the-air protocol, because the normal operation of a CDMA system includes the use of energy control algorithms

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-8i extensive. This reduced power consumption allows the life of a battery used to power the IS-95 compliant subscriber unit to extend beyond that of a GSM compliant subscriber unit.

However, many regions that already have existing GSM cellular telephone systems are reluctant to provide CDMA cellular telephone service, despite its multiple benefits. This is because the increase in performance improvement provided by a CDMA system may not be sufficient to justify the cost of providing an entirely new CDMA cellular telephone system when a previously existing system is available. This situation is in contrast to a region where a completely new cellular telephone system will be built, where the CDMA cellular telephone system is often less expensive to implement and provides superior quality service than a GSM cellular telephone system. However, if a method and system were to be devised to implement a CDMA cellular telephone system that uses part of the existing GSM cellular telephone system infrastructure, the cost of providing CDMA cellular telephone service in a region that has a cellular telephone system would be reduced. GSM in operation. If the reduction were sufficient, the benefit of the increase in

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-9i the performance provided by a CDM cellular telephone system could be justified in a greater number of places. This would allow subscribers of cellular telephone service located in those regions to also have the benefit of CDMA cellular telephone service and, therefore, such a method and system for implementing a cellular telephone system would be highly desirable.

SUMMARY OF THE INVENTION

A method and apparatus for operating a wireless telecommunication system using CDMA over the air with a GSM base-to-interface network are described. Using the GSM interface A standard, which is defined in the GSM specifications as the interface between the GSM-MSC and the BSS, the CDMA wireless telecommunication system can be implemented using a GSM-MSC that conforms to the specifications GSM. This allows CDMA wireless cellular telephone service to be provided using part of the existing operating GSM network infrastructure. In the preferred embodiment of the invention, the CDMA-based BSC communicates with the GSM-MSC via interface A as specified in existing GSM standards. However, other embodiments of the invention may use modifications to the A P1412 / 98MX interface.

-10i

GSM defined to improve the operation and functionality of the system. In accordance with one embodiment of the invention, the BSS and subscriber units are interconnected by using physically modulated radio frequency signals in accordance with CDMA techniques. In the preferred embodiment of the invention, the CDMA modulation techniques are substantially similar to those incorporated in the previously mentioned IS-95 wireless telecommunications protocol.

A high level diagram of the functional elements used to interconnect a subscriber unit and a GSM-MSC, in accordance with an embodiment of the invention, is illustrated in Figure 2. During operation of the system, the CDMA RF interface 40 provides a bidirectional interface to subscriber unit 50 and, GSM interface A transport SS7 42 provides a bidirectional interface with GSM-MSC 52. Establishing the CDMA over-the-air interface and the use of transparent signaling transport 44 that allows signaling messages defined in the GSM interface A protocol to be exchanged between GSMMSC 52 and subscriber unit 50. Processing conversion and service 46 receives and examines certain signaling messages from CDMA RF interface 40 and GSM interface A transport SS7 42 and into

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The -11ι response performs various actions, including configuring and controlling the signal processing resources 48. This configuration and control includes allocating the vocoding and de-decoding resources according to the type of service requested and invoking the CDMA-based encryption capabilities. Other actions include the allocation of the CDMA traffic channel processing resources and the selection resources at the start of the signaling exchange between the subscriber unit and the BSS or MSC. These resources are allocated for both voice and data call processing and signaling exchanges, such as registrations, between subscriber unit 50 and the system. CDMA traffic channel resources are used to perform IS-95 type CDMA modulation and demodulation functions.

A set of call processing procedures are provided to perform various tasks associated with the proper processing of a call or wireless telephone communication. These procedures include initiating the call, clearing the call, registering the subscriber unit, encrypting the over-the-air signal, authenticating the subscriber unit, and signaling message sequences and steps of Processing associated with P1412 / 98MX

These procedures are described in the detailed description of the invention. In accordance with one of the described embodiments of the invention, the call initiation and registration of the subscriber unit is effected or performed by first establishing an on-air CDMA interface between a subscriber unit and a CDMA base BSS and then establishing a telecommunications network connection between the subscriber unit and a GSMMSC. The invention also employs the use of CDMA encryption techniques. CDMA encryption techniques, used to provide subscriber information and location privacy, are initiated and terminated by GSM encryption procedures controlled by the GSM-MSC

52.

In one embodiment of the invention, transparent signaling transport 44 transparently passes signaling information between GSM-MSC 52 and subscriber unit 50. Transparent transport is defined as the exchange of signaling information between GSM-MSC 52 and the subscriber unit 50, in such a way that no intermediate processing entity examines, modifies or uses the information that will be transparently transported. Using this transparent transport mechanism allows key portions of P1412 / 98MX application layer information

-13Ε exchanged between the CDMA-based BTS and the subscriber unit is identical to the information exchanged between a TOMA-based GSM BTS and its associated GSM subscriber unit. In the preferred embodiment of the invention, the transparent signaling transport passes the messages defined in the GSM specifications as messages of the Direct Transfer Application Part (DTAP) between the GSMMSC 52 and the subscriber unit 50. DTAP messages allow GSM-MSC 52 and subscriber unit 50 to exchange data as necessary to properly process a GSM base phone call. The DTAP message classification encompasses the call handling and mobility management functions of the subscriber unit. Allowing the call handling and mobility handling messages of the subscriber unit to be transported transparently between the GSM-MSC and the subscriber unit allows the invention to use many of the procedures related to call establishment of the subscriber. Existing GSM. This, in turn, allows the invention to use the definition of existing GSM interface A, which allows operators of the GSM wireless communication system to reuse their existing operating GSM infrastructure equipment in the fielding of a

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-1414 wireless communication system that uses CDMA over the air with its GSM interface base network A.

In accordance with the present invention, a subscriber unit acquires the system, registers the system-related information it receives from the BTS on direct CDMA air channels, and is then configured to receive, process, and transmit signaling messages used to establish both the interface bidirectional CDMA as the telecommunication network connection. A subscriber unit appropriately receives and processes signaling messages from the CDMA radio resource, GSM call handling and GSM mobility management. GSM call management and GSM mobility management comprise the DTAP portion of the GSM A interface. The CDMA radio resource procedures include, but are not limited to, performing functions such as handover, system access attempts, and traffic channel establishment of the bi-directional RF signal. GSM call handling procedures include, but are not limited to, performing actions such as call establishment, supplementary service invocations, and subscriber unit alerting. GSM mobility management procedures include, but are not limited to, performing such actions as authentication of the

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-15i subscriber unit, location update and procedures to paste and detach the international identity of the mobile station.

BRIEF DESCRIPTION OF THE DRAWINGS OR FIGURES

The particularities, objects and advantages of the present invention will be more evident from the detailed description set forth below when taken in conjunction with the drawings, in which similar reference characters identify correspondingly and totally and, where:

Figure 1 is a block diagram of a cellular telephone system configured in accordance with GSM standards;

Figure 2 is a functional block diagram of message processing and service conversion architecture used to interconnect a subscriber unit and a GSM-MSC in accordance with an embodiment of the invention;

Figure 3 is a block diagram of a cellular telephone system configured in accordance with an embodiment of the invention;

Figure 4 is a diagram illustrating the various GSM interface A message formats transported using interface number 7 of the P1412 / 98MX System.

-16i Signaling;

Figure 5 is a block diagram of a base station subsystem configured in accordance with an embodiment of the invention;

Figure 6 is a message sequence diagram illustrating signaling messages transmitted during the initiation of the subscriber unit's terminated call made in accordance with one embodiment of the invention.

Figure 7 is a message sequence diagram illustrating signaling messages transmitted during the initiation of the call originating from the subscriber unit made in accordance with one embodiment of the invention;

FIG. 8 is a message sequence diagram illustrating the signaling messages transmitted during a call release originated from the subscriber unit performed in accordance with an embodiment of the invention;

Figure 9 is a message sequence diagram illustrating signaling messages transmitted during the release of the network initiated call performed in accordance with one embodiment of the invention;

Figures 10A and B are a diagram of the

P1412 / 99MX

-17ι message sequence illustrating signaling messages transmitted during registration of the subscriber unit performed in accordance with one embodiment of the invention;

Figure 11 is a block diagram of a BSC interface A configured in accordance with an embodiment of the invention; and

Figure 12 is a block diagram of a subscriber unit configured in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES

A method and apparatus for providing the wireless telecommunication service using a code division multiple access (CDMA) over-the-air interface in conjunction with a global system for interface interface network A is described. mobile communications (GSM). In the following description, the invention is exposed in the context of a radio frequency signal interface that operates or operates in accordance with the physical modulation technique of the airborne protocol signal CDMA IS-95. While the described invention is specially adapted for use with these signal modulation techniques, the use of other P1412 / 98MX protocols

-18i Code Division Multiple Access Wireless Telecommunications is consistent with the practice of the present invention. Also, while the preferred embodiment of the invention incorporates the use of GSM interface A, other A interfaces can also be used, where the use of a transparent transport mechanism between a mobile switching center and a subscriber unit is required. . The invention can also be implemented in point-to-point wireless telecommunications telecommunications.

In particular, the invention is useful in the context of the satellite-based wireless telecommunications system that incorporates the use of bent tube transmission methods that must be interconnected with the gateway of the telecommunications network, because many gateways will use the protocol of

GSM inter face A

Additionally, it should be understood that the present invention is intended to be used with various types of communications, including both voice-based communications as well as communications during which information representing digital data other than voice is transmitted.

Throughout the application the use and transmission of various types of information is described including

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-19ι messages, requests, orders, instructions and commands or orders.

It should be understood that this information is made up of electronic representations of these messages, requests, orders, instructions and commands or orders that are generated through the use of electric currents, voltage potentials, electromagnetic energy or a combination thereof.

Additionally, the following description contains the reference to various systems for the manipulation and generation of this information. In the preferred embodiment of the invention, these systems are implemented through the use of digital and analog integrated semiconductor circuits coupled to each other through various conductive connections or through the use of electromagnetic signals or both. In other cases throughout the application, several well-known systems are described in block form. This is done to avoid unnecessary clouding or clouding of the disclosure or disclosure of the present invention.

For the purposes of the present invention, the definition of Interface A GSM encompasses user data transmission and control signaling between the GSM-MSC and any connected BSCs. The control signaling is comprised of the physical signaling transport layers and the application information of the

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-20i phone call to be transported. In the GSM standard, the signaling transport layers of interface A are specified as the message transfer part (MTP) and the signaling connection control part (SCCP) of signaling system number 7 (SS7), as defined by the International Telecommunications Union (ITU), which is well known in the art. The data of the telephone call application is transported between the GSM-MSC and the BSC within the data field of the various SCCP messages.

The Figure is a block diagram of a wireless telephone system configured during normal operation in accordance with an embodiment of the invention. Base Transceiver Stations (BTS) 102 (A) - (C) are coupled to BSC 104 (A) and BTS 102 (D) - (F) are coupled to BSC 104 (B). BSCs 104 (A) and (B) are in turn coupled with GSM-MSC 106 which is coupled to public switched telephone network (PSTN) 108 (may also be PLMN). Subscriber unit 100 (A) is conducting a phone call or other communication using radio frequency (RF) signals exchanged with BTS 102 (D). The subscriber unit

<td>100 (B) is</td><td>driving</td><td>a</td><td colspan="2">call</td><td>telephone</td><td>or</td><td>other</td>

<td>communication</td><td>through</td><td>the</td><td>use</td><td>of</td><td colspan="2">the signs</td><td>RF</td>

<td>exchanged</td><td>so much with</td><td>the</td><td>BTS</td><td>102 (B)</td><td>as with</td><td>the</td><td>BTS</td>

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-2121

102 (C) - When coupled to an RF signal interface with two or more BTSs 102, as is the case with a subscriber unit 100 (B), the subscriber unit 100 (B) is said to be in soft handoff. RF signals transmitted from BTS 102 to subscriber unit 100 are referred to as forward link channels and RF signals transmitted from subscriber unit 100 to BTS 102 are referred to as reverse link channels. The BSS 105 is made up of a BSC 104 and the set of one or more BTSs 102 to which it is coupled.

In the preferred embodiment of the invention, the physical processing of the signal from both the forward and reverse link channels is performed in accordance with the CDMA signal processing techniques of the IS-95 protocol. This physical signal processing includes the use of forward and reverse link spread codes and channel codes both during transmission and reception of forward and reverse link signals. Channel codes are used to establish a set of channels over which various data sets can be transmitted by direct sequence modulation. For the forward link, the channel codes are comprised of a set of sixty-four orthogonal binary codes referred to as Walsh codes and for the reverse link, the P1412 / 98MX codes

-22ι channel are comprised of a set of binary long codes that are calculated for each subscriber unit as a function of the subscriber unit's unique identification code. Scatter codes are used to diversify the frequency range from which the data is transmitted to improve the probability of a successful transmission. This diversification is referred to as dispersion and is also performed by direct sequence modulation of the data that will be transmitted with the dispersion codes. In the preferred embodiment of the invention, channeling is accomplished by biphasic shift manipulation modulation (BPSK) and dispersion is performed by quadrature phase shift manipulation modulation (QPSK) in a manner similar to a system that complies with IS-95.

In one embodiment of the invention, the direct link channels include one more pilot channels, synchronization channels, radio location channels, and user traffic channels, each defined by modulation with a predetermined direct link channel code. Reverse link channels include one or more access channels and many of user traffic channels, each defined by modulation with a unique long reverse link code. In order for the P1412 / 98MX

-2323 transmission and reception of forward and reverse link signals is done appropriately, channel status and spreading codes used to process forward and reverse link signals during reception and transmission should be synchronized. This synchronization is achieved during call setup and is referred to as signal acquisition, for which many processes are well known in the art. The data that will be transmitted either through the forward or reverse link is divided into frames that also contain error correction bits and frame guide or head bits. The guide or head bits of the frame indicate whether the data contained in the frame is signaling data or traffic data or a combination thereof. Traffic data is the data that is transmitted by the user when the call is in progress and is normally digitized voice or audio information, but it can be any type of user data. In order to transmit a complete signaling message, it is generally necessary to transmit multiple signaling data frames, which are assembled into signaling messages by the receiving system. As indicated above, signaling messages are used to exchange any information between the various systems shown on the P1412 / 98MX

-24ι

Figure 3, necessary to establish and process a phone call. Once assembled, each signaling message contains guide bits or message heads that indicate the type of signaling message.

Still referring to Figure 3, as noted above, the GSM-MSC 106 provides the telephone switching, billing, and tracking and authorization functionality of the subscriber unit. GSM-MSC 106 and BSC 104 communicate in accordance with the GSM interface protocol A which is part of the GSM standard. In order to establish a telephone call connection using GSM-MSC 106, a particular set of signaling messages must be generated in a particular order containing a particular set of information. That is, BSC 104 must generate and transmit the appropriate signaling set to the GSM-BSC in the proper order, depending on the required network connections and the signaling messages received from the GSM-MSC 106. The order, information, and format associated with these signaling message sets are defined by the A GSM interface protocol. As can be expected, the order, information and format differ substantially from any interface associated with a comparable MSC that operates or operates within a CDMA cellular telephone system. In a similar way, a unit

Ρ1412 / 9ΘΜΧ

-25ι subscriber 100 operating in accordance with IS-95 or another CDMA-based protocol, must exchange a predetermined set of messages with BTS 102 in a predetermined order and in a predetermined format to properly establish and process a call telephone. Also as can be expected, the CDMA over-the-air interface differs substantially from the over-the-air interface associated with wireless GSM telecommunications systems.

The signaling messages associated with the GSM interface A protocol are separated into two categories: The Direct Transfer Application Part (DTAP) messages and the BSS Management Application Part messages (BSSMAP) . The DTAP contains data relevant to the operation of subscriber unit 100 and MSC 106, and therefore does not directly affect the operation of BSS 105. BSSMAP messages are generally associated with the operation of BSS 105 and can cause resource allocation or provide the information necessary for the proper operation of BSS 105. A BSSMAP message can affect the entire operation of the ·

BSS 105 or, only the operation of a single phone call. also, in accordance with interface A of the

GSM, signaling messages are transmitted through the signaling link of the Signaling System

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-2626

Number 7 (SS7) and the message transfer part (associated MTP and signaling connection control part (SCCP). MTP uses three message formats to transmit binary data over a serial link. All three formats Message units are referred to as message signal units (MSU), link state signal units (LSSU), and fill signal units (FISU). The fields associated with each message format are illustrated in Figure 4 with the number of bits associated with each field indicated below. Messages are separated by the use of a flag byte (FL) that contains a loaned logical zero from a series of six logical ones followed by a logical zero (01111110). Within messages defined by flag bytes, a logical zero is inserted into any string of more than five logical ones.

Each message format is comprised of a guide or head section containing a reverse reverse sequence number (BSN), a reverse or reverse indication bit (BIB), a forward sequence number (FSN), a advance indication bit (FIB) and a length indicator (LI) followed by two regulator bits. Additionally, each message format includes a set of check bits (CK) inserted just before the termination of the flag byte.

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-27i

For FISUs, no additional data fields are included. For LSSUs, one or two bytes of the status field (SF) are included, indicating one of six status indications dealing with the alignment and out of order status. For MSUs, a service byte of the signal byte and two or more bytes of the signal information field (SIF) are included. Since each message format contains a different amount of information, the message type is determined from the length indicator (LI) field. Signaling messages transmitted in accordance with GSM interface A are sent via an MSU with the data associated with the GSM interface A signaling message placed in the SIF. More particularly, messages transmitted in accordance with GSM interface A are placed in SCCP messages that include a route or routing label (RL), an SCCP message type code, an SCCP guide or head, and a data field. SCCP as shown. The SCCP message type code is normally considered a subfield of the SCCP guide or head. The SCCP message is terminated with the end of the optional parameters flag (EOP). · If the BSSMAP message carried within the SCCP message is the type that relates to a single phone call, the phone call it is with

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-2828 associated message is indicated in the connection identifier field of the SCCP head or guide (not shown). A BSSMAP or DTAP message is contained within the SCCP data parameter with the message type indicated by the Discrimination Bit (DIS) located at the beginning of the SCCP data field. If the BSSMAP message will be transmitted, the length is indicated in the length field (LEN). After the length is the BSSMAP message type and the rest of the message. If a DTAP message is being transmitted, the length is indicated in the length (LEN) field and the subcategory of the DTAP message is indicated in the protocol discrimination field. Any additional data associated with the particular DTAP message including the message type is placed in the message data field.

Figure 5 is a block diagram of BSS 105 configured to provide CDMA over-the-air telecommunication service in conjunction with a GSM interface protocol network interface in accordance with an embodiment of the invention. BTSs 102 are coupled to BSC 104 via wired or wired links, which in the preferred embodiment of the invention constitute a Ti or El connection, although other connections may be substituted, including the microwave link. Within BSC 104, the CDMA 200 interconnect subsystem is coupled to the P1412 / 98MX set of BTSs

-29Ε

102 shown. The CDMA interconnect subsystem 200 is also coupled to call control processor 200, selection subsystem 204 and interface A 206 of the BSC. The CDMA 200 interconnect subsystem serves as a message and traffic router between connection coupled entities and in the preferred embodiment of the invention is comprised of an asynchronous fixed length packet transport system. The data processing and service option system 210 is coupled to the selection subsystem 204 and exchanges traffic data with the switch 212. The switch 212 provides an interface or interconnection with the GSM-MSC 106 of Figure 2, which It consists of traffic and signaling data and also exchanges control data with the call control processor 202. In the preferred embodiment of the invention, this signaling data is transmitted using the ITU Signaling System Number 7 (SS7) protocol as specified in GSM interface protocol A, the use of which is well known in the art. Each of the connections shown within BSC 104 is a high-speed digital connection, such as fast Ethernet, the use of which is also well known in the art. In alternative embodiments of the invention, switch 212 may be replaced with a more cross connection device

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-30Ε simple, causing BSC interface A 206 to dock directly to GSM-MSC 106. However, the use of switch 212 is preferred, because it allows BSC 104 to dock with multiple MSC systems if necessary, each of which can provide alternative types of network service including IS41 service, the use of which is well known in the art. If BSC 104 is coupled to multiple MSC systems, additional BSC interface systems similar to interface A 206 BSC are used in the preferred embodiment of the invention, not all of these should incorporate the use of GSM interface A protocol.

In the preferred embodiment of the invention, the systems that make up BSS 105 communicate and exchange traffic and signaling data by using an internal BSS protocol in which fixed-length data packets are exchanged between various other systems by means of the COMA 200 interconnection subsystem or through direct routing between the two systems involved. The COMA 200 interconnect subsystem performs this routing by using an address contained in each fixed-length data packet. Generally, a first system that transmits a data packet to a second system places the address of that second system in the data packet and P1412 / 98MX

-31i then provides the data packet to the CDMA interconnect subsystem 200. In the case of some adjacent systems, such as the selection subsystem 204 and the data processing and service option system 210, the data packets pass directly. If a particular fixed-length packet contains traffic data or signaling data, this is indicated by guide bits of the packet contained in each packet. Data packets containing traffic data are referred to as traffic packets and data packets containing signaling data are referred to as signaling packets. Control information is also exchanged between some systems within BSS 105 through the use of dedicated or dedicated connections, such as that shown between call control processor 202 and switch 212. Other methods for networking various systems within BSS 105 shown in Figure 5, other than the CDMA 200 interconnect subsystem, are consistent with the operation of the present invention.

A signaling message constitutes a complete instruction used to control both the operation of the various systems constituting the BSS, as well as to exchange information with the subscriber unit 100 or the GSM-MSC 106. A message from P1412 / 98MX

-32I full signaling is transmitted by one or more signaling packets that are assembled by the receiving system to generate the signaling message to be transmitted. In accordance with an embodiment of the present invention, a subcategory of the signaling message that is transmitted through BSS 105 is defined without affecting the operation of BSS 105. For the purposes of this application, signaling messages are referred to as transport messages and the availability of transport messages forms a transparent transport function within BSS 105. The transparent transport function is generally used to exchange a specific category of messages. signaling between GSM-MSC 106 and subscriber unit 100, defined as DTAP messages, by means of BSS 105. During operation of BSS 105, call control processor 202 and interface A 206 of BSC configure and control the various other systems within BSS 105 through the use of other signaling messages and, generally throughout the request, any configuration or other control exercised by call control processor 202 and BSC interface A 206 is effected by use of these signaling messages, that pass as described above in the preferred embodiment of the invention, although the use of other message passing mechanisms such

P1412 / 98MX

-33ι as the direct interconnection between systems is also consistent with the present invention. In the preferred embodiment of the invention, call control processor 202 and interface A 206 of BSC are implemented through the use of computer systems controlled by software instructions (not shown).

One type of configuration and control performed by BSC interface A 206 includes the allocation of selection resources within the selection subsystem 204. A selection resource provides a two-way interface between subscriber unit 100 and any system within BSC 104 by means of of one or more BTSs 102. Features associated with this bi-directional interface include matching or matching multiple copies of a data table generated by two or more BTSs and selecting the highest quality data table to

<td>from the</td><td>set of copies for processing</td>

<td>additional.</td><td>This selection is made based on the</td>

<td>information</td><td>of quality indication placed on each</td>

frame for each BTS 102. Multiple copies of a frame are generated when the subscriber unit 100 is coupled on multiple RF interfaces with multiple BTSs 102 during a soft transfer condition. Additionally, a selection resource receives the data packets directed to a subscriber unit 100 and

P1412 / 98MX

-34ι issues a copy of the data packet to each BTS 102 coupled in an RF interface with the subscriber unit 100. Each selection resource has its own internal address, so that packets associated with the call to be processed can be routed to that selection resource within the selection subsystem 204. Each selection resource also tracks the set of BTSs 102 with which the subscriber unit 100 to which it is assigned is interconnected. In the preferred embodiment of the invention, the selection facility is comprised of a microprocessor or digital signal processor controlled by software instructions stored in a memory unit also located within the selection subsystem 204 (not shown).

An interface A 206 BSC also configures data processing and service options system 210 to process data from selection subsystem 204 in a variety of ways based on the services needed to process the phone call. The types of signal processing services provided include vocoding and decoding of voice traffic data associated with a phone call, modulation and demodulation of tones and other signals used for the transmission of fax and other digital data. through a normal PSTN connection, and P1412 / 98MX

-3535 encryption of user and signaling data. In the preferred embodiment of the invention, signal processing is performed using a digital signal processing integrated circuit located within data processing and service options system 210 and controlled by using instruction instructions. software stored in a memory system, the use of which is well known in the art (not shown). Another function performed by interface A 206 BSC is to receive DTAP signaling messages from GSM-MSC 106 transmitted in accordance with interface A and transport these signaling messages to appropriate subscriber unit 100 by placing the message in the transport messages and issuing the transport messages to the selector resource associated with the

<td>phone call.</td><td>With the</td><td>receiving</td><td>the</td><td>messages</td><td>of</td>

<td colspan="3">transport, the selector resource will emit</td><td>the</td><td>message</td><td>of</td>

<td>transport to</td><td>Unit</td><td>subscriber</td><td> 100</td><td>through</td><td>the</td>

<td>traffic channel</td><td>user</td><td>direct CDMA.</td><td></td><td></td><td></td>

<td>Is according</td><td>Indian</td><td>previously,</td><td>the</td><td>s data</td><td>I know</td>

They exchange between the BTS 102 and a subscriber unit 100 by multiple frames containing guide bits or frame headers indicating the type of data contained in that frame. In the preferred embodiment of the invention, both signaling and traffic data can P1412 / 98MX

-361 be transmitted in a single frame in accordance with the IS-95 standard. There is no address contained in the box during on-air transmission since the destination and source of each box are indicated by the channel code used to modulate the data. In the preferred embodiment of the invention, each frame transmitted over the reverse link is received by a particular channel processing element (not shown) within a BTS 102. Each channel processing element in turn knows the internal address of the selector resource that processes the call, and after extracting a frame from the reverse link signal, the channel processing element outputs the frame to the selector resource. The selector facility then assembles the signaling messages from the frames containing signaling data and determines the type of signaling message based on the leading or leading bits of the signaling messages contained in the signaling message. Transport signaling messages are transparently routed to the A 206 BSC interface by the selection facility using the BSS transport messages described above. An A BSC interface proceeds to place a connection identifier associated with the phone call in the SCCP head or guide field based on the

P1412 / 98MX

-3737 selection facility that transmits the transport signaling message and for transparently broadcasting the transport signaling messages to the GSM-MSC in accordance with

Inter face A. If the message is a non-transport or local signaling protocol message, the selector facility and BSC interface A 206 will process the message internally.

In accordance with an embodiment of the present invention, various procedures must be performed by orderly exchanging signaling messages between the various systems shown in Figure 5, in order to appropriately process a phone call. The various procedures include initiating the call, clearing the call, and registering the subscriber unit. Figures 6-10 are a set of message sequence diagrams illustrating the signaling messages exchanged during the call initiation, call clearing and subscriber unit registration processes in accordance with one embodiment of the invention. The vertical lines shown in Figures 6-10 are each associated with the system identified in the box at the top of each line. The systems are subscriber unit 100, BTS 102, selector subsystem 204, call control processor 202, processing system 210

Ρ1412 / 9ΘΜΧ

-381 for data and service options, Inter face A 206 BSC and GSM-MSC 106. A horizontal arrow running between two vertical lines indicates the exchange of a signaling message between the associated systems. Time progresses from the top to the bottom, so the most upright horizontal lines occur before those downward horizontal lines on the page. As indicated at the bottom of each page, the messages exchanged between the subserip unit 100 and the BTS 102 are transmitted through the two-way over-the-air interface and the messages exchanged between the GSM-MSC 106 and the A 206 BSC interface are transmitted from compliance with the A GSM interface.

As indicated above, a GSM signaling message exchanged between GSM-MSC 106 and Inter face A 206 BSC is carried within an SCCP signaling message that is contained within a conformance message signaling unit (MSU) with the SS7 standard, upon receipt of the SCCP signaling message, interface A 206 BSC first determines whether the message is associated with a particular communication or is directed to the operation of the entire BSS, by examining the code field of the SCCP message type. If the message is associated with a particular communication or a phone call, the A 206 BSC interface determines that P1412 / 98MX

-3939 communication by using a connection identifier contained in the SCCP guide or head. An A 206 BSC interface then determines whether the message is a DTAP or BSSMAP message by examining the discrimination field of the A GSM interface signaling message. If the GSM signaling message is a DTAP message, the A BSC interface proceeds to transparently transport the signaling message by means of a transport message as described above. If the message is a BSSMAP message, the BSSMAP interface determines the specific BSSMAP message by examining the BSSMAP message type field. Based on the BSSMAP message type, Interface A BSC performs several steps as described above.

It should also be noted that for the purposes of the following description, the signaling messages exchanged between the selection subsystem 204 and the subscriber unit 100 are displayed by a single horizontal line between the two systems. However, the signaling message actually passes through one or more BTSs 102. The single line is used for ease of drawing when the signaling message does not require control processing or resource allocation by the BTS 102. Similarly, the signaling messages exchanged between Interface A 206 BSC and the GSM-MSC

P1412 / 98MX

-40t

106 pass through switch 212, however a single line is shown because switch 212 does not effect relevant to the present invention.

The on-air CDMA channel used to transmit a subscriber unit 100 is message towards indicated in continuation of the message associated with indicates an indicates the channel from the channel channel of a "P parenthesis indicating a direct, A to link access reverse and a T that of user traffic direct link or reverse link user traffic depending

Additionally, of the in the establishment of management channel

Transmission figures.

and 10 the process associated with setting up the left subscriber user interface of the login process.

100 the direct and reverse link traffic channel enters the unit the extreme figure. The telecommunications establishment involved in the extreme left.

network is to establish a network connection with another telecommunications system called and is also indicated to the

Transparently routed signaling messages via transport are indicated by the associated signaling message

P1412 / 98MX use of xport notation messages with parentheses and son

-41i referred to as transport messages throughout the specification.

In Figures 8 and 9, the start of network release, indicated to the extreme left of the figures, is the process of initiating the breakdown and release of the network resources involved in the phone call. Also, in Figures 8 and 9, the traffic channel interface breakdown is the process of releasing the resources associated with the bi-directional radio frequency signal interface between the subscriber unit 100 and the BSS 105 (Figure 3). It should also be noted that the message sequence diagram shown in Figures 6-10 does not show each message transmitted but only those particularly relevant to the present invention.

Some signaling messages discussed below are also not shown for ease of drawing.

Additionally, each display message that is transmitted within the BSS

105, is exchanged in accordance with the internal packet-based protocol described above, and therefore passes through the CDMA interconnect subsystem 200 of Figure 5 in the preferred embodiment of the invention.

Figure 6 is a sequence diagram of the message of a subscriber unit terminated call initiation procedure performed in accordance with a

P14L2 / 9BMX

-42i embodiment of the invention. The subscriber unit terminated call initiation procedure results from the initiation of a telephone call or communication by a telecommunication entity other than subscriber unit 100 that interfaces with the wireless telecommunication system shown in Figure 4, such as a PSTN subscriber unit 108, a wireless subscriber unit 100 that interfaces with other wireless telecommunication systems, or, even a data terminal. The initiation of the ended call of the subscriber unit begins when the GSM-MSC 106 transmits the paging message 300 to interface A 206 BSC in accordance with the protocol of interface A. In accordance with the interface A protocol, the radiolocation 300 message indicates that the subscriber to be radio localized, identified by the identity of the international mobile subscriber, is a cell identifier list indicating the most recently associated set of cells with the temporary mobile subscriber unit.

An A 206 interface

BSC first examine the radiolocation message

300 received to determine if it is a BSSMAP message.

After identifying the message of

P1412 / 98MX

-43i paging 300 as BSSMAP message interface A 206 BSC determines that paging message 300 is a paging message by examining the 'BSSMAP message' type field. With the determination that the paging message 300 is a paging message, Interface A 206 BSC proceeds to generate a set of signaling messages to establish a bidirectional CDMA modulated RF channel between BTS 102 and subscriber unit 100 a the one addressed by the paging message 300. In the preferred embodiment of the invention, this set of signaling messages begins with the transmission of the radiolocation request 302 BSS, which includes the cell identifier list, to the call control processor 202. The call control processor 202 responds by transmitting the request

303 BTS towards a set of BTSs 102 radiolocation indicated by the cell identifier list. Every

BTS 102 responds by transmitting radiolocation message 304 to the associated cell via the forward link radiolocation channel.

If the paging is received by the subscriber unit 100, it responds by transmitting the channel request message 306 to a BTS 102 via the

Channel request message 306 may contain information about the type of

P1412 / 98MX

-4444 service requested for the call, if this information

<td>It's included</td><td>Jan</td><td>1 message from</td><td>radiolocation</td><td> 304.</td><td></td>

<td>The</td><td>BTS</td><td>answers</td><td>the application of</td><td>channel</td><td> 306</td>

<td>transmitting</td><td>the</td><td colspan="3">310 BSS channel request to</td><td>the</td>

<td>interface A</td><td> 206</td><td>BSC and al</td><td>transmit the</td><td>message</td><td>of</td>

acknowledgment or acknowledgment of receipt 308 BTS towards the subscriber unit 100 through the radiolocation channel.

Transmission of the acknowledgment or acknowledgment message 308 BTS is optional in the preferred embodiment of the invention. Interface A 206 BSC continues to establish the bi-directional user traffic channel interface by responding to channel request 310 BSS with the transmission of call setup request 312 BSS to call control processor 202. Call control processor 202 allocates selector and service resources for the call and indicates the result of the assignment to interface A 206 BSC in call setup response 314 BSS. On receipt of the 314 BSS call setup response, the A 206 BSC interface transmits the call setup request

316 from the selector to the selection subsystem 204. The selection subsystem 204 starts the assigned selector resource to process the call and indicates this to interface A 206 BSC with the selector call installation response 318. Upon receipt of the response

P1412 / 9BMX

Selector call setup 4545 -4545 interface A 206 BSC transmits radio link setup request 319 to selection subsystem 204. Selection subsystem 204 responds by transmitting channel resource request 320 to BTS 102.

Upon receipt of the channel 320 resource request, the BTS 102 allocates the channel processing resources to modulate and demodulate the forward and reverse link user traffic channels associated with the phone call and transmit the resource response message from channel 322 to selection subsystem 204. Selection subsystem 204 responds by transmitting connection request 324 to BTS 102 which responds by transmitting connection response 326 to selection subsystem 204. Selection subsystem 204 then transmits null traffic data 328, the traffic data message of start 330 and null traffic data 332 to BTS 102. BTS 102 responds to start traffic data message 330 and null traffic data 332 by transmitting null traffic data 336 to subscriber unit 100 via the direct link user's traffic channel. Selection subsystem 204 also transmits the indication of radio link resource 334 to interface A 206 BSC. Upon receiving the indication of the radio link resource 334, the interface

Ρ1412 / 9ΘΜΧ

-4646

A 206 BSC transmits channel assignment message 338 BTS to ΒΤΞ 102 which responds by transmitting channel assignment message 340 to subscriber unit 100 via the forward link radiolocation channel. Subscriber unit 100 uses the assigned channel information contained in the channel allocation message 340 to begin processing of the assigned forward link traffic channel and transmits the preamble 342 of the reverse link traffic channel on the forward traffic channel. reverse link user, so that BTS 102 can acquire the reverse link traffic channel of subscriber unit 100. Once the reverse link traffic channel has been acquired, the BTS 102 transmits the start reverse link message 344 to the selection subsystem 204. The selection subsystem 204 responds by transmitting acknowledgment or acknowledgment of the reverse link 346 to the subscriber unit 100 via the direct link traffic channel. Additionally, selection subsystem 204 transmits radio link installation response message 348 to interface A 206 BSC. Upon receipt of acknowledgment or acknowledgment of reverse link 346, the bidirectional RF inter face has been established.

Having established the forward and reverse link traffic channel interfaces with BTS 102, the

P1412 / 98MX

-4747 subscriber unit 100 initiates a telecommunication network connection establishment procedure by transmitting the radiolocation response 350 to selector subsystem 204. Location response 350 causes selector subsystem 204 to transmit radiolocation response 352 BSS to interface A 206 BSC. Interface A 206 BSC receives radiolocation response 352 BSS, indicating that subscriber unit 100 is ready to establish a network connection, stores the class mark information of subscriber unit 100 and initiates an SCCP connection by sending a request connection SCCP containing the full layer information message 3 354 to the GSM-MSC 106 in accordance with the inter face A protocol. The full layer information message 3 354 contains the contents of the paging response message 352 BSS and is part of the A GSM interface protocol and is therefore well known in the art. GSM-MSC 106 responds by transmitting the cipher mode command 358 to interface A 206 BSC. The cipher mode command 358 contains the encryption information including an encryption key, the list of possible encryption algorithms used based on the capabilities of the subscriber unit 100, and the cipher response mode that can request the identity of the international mobile team.

P1412 / 98MX

-4848

By determining that the cipher mode command 358 is a BSSMAP message and then further determining that it is a cipher mode command, Inter face A 206 BSC selects an algorithm from the possible encryption algorithms and transmits the cipher mode command 360 BSS to selector subsystem 204. Subsystem 204 initiates encryption procedures over the air by transmitting the cipher mode command 362 to subscriber unit 100 via the direct link traffic channel. After processing of the cipher mode command 362, the subscriber unit 100 transmits the cipher mode complete message 364 via the reverse link traffic channel to the selection subsystem 204. On receipt of the full encryption mode message 364, the selection subsystem 204 begins to perform encryption-decryption on all additional signaling data and on the call data associated with the telephone call by changing to a private reverse link channel code or long code, substantially in accordance with the IS-95 standard. It should be noted that the other encryption and encryption methods (code encryption) are consistent with the operation of the present invention. The selection subsystem 204 then transmits the cipher mode complete message 366 BSS to interface A 206 BSC indicating that the cipher mode configuration operation has been completed. The

P1412 / 98MX

-49i interface A 206

BSC responds by transmitting the full command in encryption mode

368 indicating that the chosen encryption algorithm and the international mobile equipment identifier, if requested, when

GSM-MSC 106 in accordance with the Interface protocol

TO.

then the

106 transmits installation message 370 to interface A 206

BSC.

Installation message 370 contains various types of information about the telephone call to be established, including the type of service, the transmission rate, the type of data to be transmitted, and the type of encryption.

The use of installation message 370 is part of Interface A protocol.

GSM and is therefore well known in the art.

When determining installation 370 is a message

DTAP, interface A

206 BSC transparently transports the message content via transport message 372 to selection subsystem 204.

In the preferred embodiment of the invention, the interface A 206 BSC does not know that the installation message 370 is in fact an installation message, but only that it is a DTAP type message since it does not look beyond the discriminator bits. This simplifies the required processing of the A 206 BSC interface and enables transparent transport. When determining that the transport message

P1412 / 98MX

-5050

372 is a transport message, the selection subsystem 204 issues the content of the message via transport message 374 to subscriber unit 100 via the forward link traffic channel. After receiving the transport message 374, the subscriber unit 100 passes the content of the message, which is the DTAP installation message, to the GSM message processing portion of the subscriber unit 100. That portion of subscriber unit 100 responds by transmitting the call confirmation to selection subsystem 204 within transport message 376. A call confirmation either confirms the type of service set forth in installation message 370 or proposes a type alternative service. Selection subsystem 204 transparently transports the contents of transport message 376 to interface A 206 BSC via transport message 378 containing the call confirmation. With the continuation of the transparent transport processes, the A 206 BSC interface issues the message content through the 380 DTAP call confirmation message to the GSM-MSC 106 in accordance with the A GSM interface protocol.

On receipt of call confirmation message 380, GSM-MSC 106 transmits assignment request 382 to interface A 206 BSC. The P1412 / 98MX allocation request

-51ι

382 indicates the channel type, priority, circuit identity code (network time slot), downlink DTX flag (variable speed transmission), interference band (frequency hopping) to be used, and the Class 2 brand information (type of subscriber unit). The channel type is the type of data that will be transmitted during transmission, for example, fax, voice, or signaling. Allocation request 382, ​​a BSSMAP message, causes interface A 206 BSC to negotiate the type of CDMA service required to process the phone call with subscriber unit 100. This transaction begins with the transmission of service request 386 BSS to the selection subsystem 204, which responds by transmitting service request 388 to subscriber unit 100 via the direct link traffic channel. The service request 388 indicates the parameters of the radio link necessary in order to provide the requested data service including, the data rate or speed, and the subscriber unit 100 responds by transmitting the service response 389 to the selector subsystem 100, which indicates whether the type of radio link is acceptable. If the service response 389 indicates that the service type is acceptable, the selector subsystem 204 transmits the service connection message 390 to the subscriber unit 100 by means of the

P1412 / 98MX

-5252 forward link traffic channel, causing subscriber unit 100 to transmit the complete service connection message 391 to selection subsystem 204 via reverse link traffic channel.

Selector subsystem 204 then indicates the successful service transaction to interface A 206 BSC by transmitting service response 392 BSS. On receipt of the 392 BSS service response, the A 206 BSC interface allocates the resources to process the call in accordance with the service type by transmitting the 384 BSS resource allocation message to the data processing system and service options 210 . The data processing and service options system 210 then allocates call processing resources to process any received traffic data. In an alternative embodiment of the invention, the allocation of the service options resource is performed in response to the channel request message 310. Additionally, an interface A 206 BSC assigns a connection within switch 212 to create a traffic channel between GSM-MSC 106 and service options and data processing system 210 to carry the traffic data associated with the call ( the message to switch 212 is not shown). Interface A 206 BSC then indicates that the service transaction has been

P1412 / 98MX

-5353 completed by transmitting the complete assignment message 394 to the GSM-MSC in accordance with the Interface A GSM protocol.

Upon termination of the service transaction, the GSM message processing portion of the subscriber unit 100 indicates to the GSM-MSC 106 that it is alerting the user of the subscriber unit 100 by transmitting an alert message via the transport message 400. The alert message is transparently transported by selector subsystem 204 to interface A BSC via transport message 398, and then to GSM-MSC 106 by interface A BSC via alert message 396 DTAP. At this point, GSM-MSC 106 can generate the ringback tone back to the calling party. If the subscriber unit 100 answers the call, it indicates that the response event to the GSM-MSC 106 transmitting a connection within the transport message 402 to the selection subsystem 204 via the reverse link traffic channel. The connection is transported transparently by selector subsystem 204 to Interface A BSC via transport message 404 and then to GSM-MSC 106 via interface A BSC via connection message 408 DTAP. Upon receipt of the connection message 408, the GSM-MSC ceases the return call if the connection message is provided and transmitted

P1412 / 98MX

-5454 acknowledgment or acknowledgment of connection 410 to interface A 206 BSC. Interface A 206 BSC transparently issues the connection acknowledgment or acknowledgment message 410 to selection subsystem 204 by means of transport message 412. Selection subsystem 204 then continues transparent transport by transmitting the message of transport 414 to subscriber unit 100 via the direct link traffic channel. Upon receipt of the transport message 414 by the subscriber unit 100, a stable call state has been established and the process of generating the finished call from the subscriber unit is completed.

Figure 7 is a message sequence diagram illustrating signaling messages transmitted during a call initiation procedure originating from the subscriber unit, performed in accordance with one embodiment of the invention. A call initiation procedure originating from the wireless subscriber unit results from a telephone call initiated by a subscriber unit 100 of Figure 2. The subscriber unit originated call initiation procedure begins with the channel 506 request message transmitted from the subscriber unit 100 to the BTS 102 via the reverse link access channel. Ρ1412 / 9ΘΜΧ

-5555

In the preferred embodiment of the invention, the channel request message 506 contains information about the type of service being requested, however this information may be provided in other messages in alternative embodiments of the invention. BTS 102 responds to channel request 506 by transmitting channel request 510 BSS to interface A 206 BSC and transmitting acknowledgment message 508 BTS to subscriber unit 100, although transmission of acknowledgment message 508 BTS is optional on the preferred embodiment of the invention. Interface A 206 BSC responds by generating a set of signaling messages to establish a bidirectional CDMA modulated RF signal interface between subscriber unit 100 and BTS 102. The process of establishing this bidirectional interface begins when interface A 206 BSC transmits the 512 BSC call setup request to call control processor 202. The call control processor 202 allocates the selector and service resources for the call and indicates the result of the assignment to Interface A 206 BSC in the call installation response 514 BSS. On receipt of BSS call installation response 514, interface A 206 BSC transmits selector call installation request 516 to selection subsystem 204. Selection subsystem 204 initializes the assigned selector resource and P1412 / 98MX

-5656 indicates this to interface A 206 BSC with call setup response from selector 518. On receipt of call setup response 518, interface A 206 BSC transmits radio link setup request 519 to selection subsystem 204. Selection subsystem 204 responds by transmitting channel 520 resource request to BTS 102.

Upon receipt of the channel 520 reuse request, the BTS 102 allocates channel processing resources to modulate and demodulate the forward and reverse link user traffic channels associated with the phone call, and transmit the resource response message from channel 522 to selection subsystem 204. Selection subsystem 204 responds by allocating a selection resource for call processing and transmitting connection request 524 to BTS 102, which responds by transmitting connection response 526 to selection subsystem 204. Selection subsystem 204 then transmits Null traffic data 528, traffic data message 530 and null traffic data 532 to BTS 102. The BTS 102 responds to start the traffic data message 530 and the null traffic data 532 by transmitting the null traffic data 536 to the subscriber unit 100 via the direct link traffic channel. Selection subsystem 204 also transmits

P1412 / 98MX

-57ι the radio link resource message 534 to interface A 206 BSC. Upon receipt of the radio link resource message 530, interface A 206 BSC transmits channel assignment message 538 BTS to BTS 102 which responds by transmitting channel assignment message 540 to subscriber unit 100 via the direct link radiolocation.

Subscriber unit 100 uses the assigned channel information contained in channel assignment message 540 to begin processing the data received via the assigned forward link traffic channel. It also transmits preamble 542 of the reverse link traffic channel so that BTS 102 can acquire the reverse link traffic channel from subscriber unit 100. Once the reverse link signal has been acquired, the BTS 102 transmits the start reverse link message 544 to the selection subsystem 204. The selection subsystem 204 responds by transmitting the acknowledgment or acknowledgment 546 of the reverse link to the unit Subscriber 100 through the direct link traffic channel. Additionally, selection subsystem 204 transmits message 548 from the radio link resource to interface A 206 BSC. At this point, the two-way link has been established and the installation of the network connection begins.

P1412 / 9BMX

-5858

Upon receipt of the reverse link acknowledgment or acknowledgment message 546, the subscriber unit 100 initiates the installation of the network connection by transmitting the call or service request 550 to the selection subsystem 204 via the traffic channel of reverse link. Selection subsystem 204 responds by transmitting BSS call handling service request 551 to interface A 206 BSC. Interface A 206 BSC stores the class mark information contained in the message, generates the full three-layer information message 552 containing the information sent in the call handling service request 551 and initiates an SCCP connection by sending the complete three layer information message 552 within an SCCP connection request message to the GSM-MSC 106 in accordance with interface protocol A. The full three layer information message 552 is part of the GSM Interface A protocol and is therefore well known in the art.

GSM-MSC 106 responds by transmitting authentication request 553 to interface A 206 BSC. Interface A 206 BSC identifies message 553 as a DTAP message and transparently broadcasts the content of the message to selection subsystem 204 using transport message 554. Selection subsystem 204

P1412 / 98MX

-59i determines that transport message 554 is of a transport message type and transparently broadcasts the message content to subscriber unit 100 by transmitting transport message 555 over the forward link traffic channel. Subscriber unit 100 receives transport message 555 and transports the content to an internal GSM message processing portion that responds by transmitting transport message 556 containing an authentication response to selector subsystem 204 via the forward link traffic channel . By determining that transport message 556 is a transport message, selection subsystem 204 transparently broadcasts the message content to interface A 206 BSC via transport message 557. Interface A 206 BSC continues with transparent transport by sending the 558 DTAP authentication response to the GSM-MSC 106 in accordance with the A GSM interface protocol.

GSM-MSC 106 responds by transmitting the 559 mode command to interface A 206 BSC. With the determination that message 559 is a BSSMAP message and further determining then that it is a cipher mode command, interface A 206 BSC begins encryption start procedures over the air by transmitting the cipher mode command 560 BSS to the

Ρ1412 / 9ΘΜΧ

-6060 selection subsystem 204. Upon receiving the 560 BSS mode command, the selection subsystem 204 transmits the command mode 562 to subscriber unit 100 via the direct link traffic channel. After processing the cipher mode command 562, subscriber unit 100 transmits the full cipher mode message 564 over the reverse link traffic channel to selection subsystem 204 and begins encrypting all subsequent transmissions. Upon receipt of the message 564 in full encryption mode, selector subsystem 204 begins encryption-description on all additional signaling and call data associated with the phone call. In the preferred embodiment of the invention, this encryption is performed using private channel codes in accordance with the IS-95 specification; however, the use of alternative encryption methods is consistent with the operation of the present invention. The selection subsystem 204 then transmits complete message 566 in BSS cipher mode to interface A 206 BSC. The A 206 BSC interface responds by transmitting the full 568 command in encryption mode to the GSM-MSC 106 in accordance with the A GSM interface protocol indicating the configuration for encryption is complete.

Having established a bidirectional channel

P1412 / 98MX

Sure -61i, the subscriber unit 100 transmits the installation information to the GSM-MSC 106 by transmitting the installation message 570 to the selection subsystem 204. The installation message 570 contains various types of information about the telephone call to be established, including the dialed digits, the type of service, the rate or speed of transmission, the type of data to be transmitted and the type of voice encoding. Selection subsystem 204 transparently broadcasts the installation message via transport message 572 to Interface A 206 BSC. Interface A 206 BSC continues the transparent transport of the installation message by transmitting transport message 574 to GSM-MSC 106 in accordance with the A GSM interface protocol. After receiving transport message 572 and initiating connection to the calling party, GSM-MSC 106 transmits transport message 576 containing a call procedure message to interface A 206 BSC. A call procedure message indicates that the network connection will be established and that no more call setup information will be accepted. Interface A 206 BSC responds by transparently transmitting the call procedure message within transport message 578 to selection subsystem 204. Selection subsystem 204 responds by transmitting the

P1412 / 98MX

-62i transport message 580 containing the call procedure message to the subscriber unit 100 via the direct link traffic channel.

After transmitting call procedure message 576, GSM-MSC 106 also transmits assignment request 582 to interface A 206 BSC. In response, interface A 206 BSC continues to configure the BSS to process the call by transmitting assignment request 586 BSS to selection subsystem 204, which responds by transmitting service connection 589 to subscriber unit 100 via the direct link traffic. In response, the subscriber unit 100 transmits the service connection complete message 591 to the selection subsystem 204 via the reverse link traffic channel indicating that the service type is acceptable. (Note that the use of both a service request message and a service response message as shown in Figure 4 is omitted here, since it is very likely that the service will be acceptable to the subscriber unit 100, because subscriber unit 100 made the initial service request when it initiated the phone call).

Selection subsystem 204 proceeds to transmit service response 592 BSS to interface A 206 BSC and interface A 206 BSC responds by transmitting message 594

P1412 / 98MX

-63i complete assignment to the GSM-MSC in accordance with the A GSM interface protocol. To allocate resources for call processing according to the type of service indicated in allocation request 582 and in service response 592 BSS, interface A 206 BSC also transmits resource allocation message 584 to system 210 data processing and service options. Additionally, Interface A 206 BSC assigns a connection within switch 212 (Figure 3) to create a traffic channel between GSM-MSC 106 and data processing system 210 and service options to carry associated traffic data. to

<td colspan="2">call (the message</td><td colspan="2">to switch</td><td> 212</td><td>not shown).</td><td></td>

<td>With</td><td>the</td><td>reception</td><td colspan="2">of the</td><td>full message</td><td>of</td>

<td>allocation 594,</td><td>the</td><td>GSM-MSC</td><td> 106</td><td colspan="2">convey the message</td><td>of</td>

<td>alert 596 to the</td><td colspan="2">interface A</td><td> 206</td><td>BSC</td><td>in accordance with</td><td>the</td>

<td>protocol of the</td><td colspan="3">interface to GSM,</td><td>than</td><td>responds by issuing</td><td>in</td>

The message is transparently made to the selection subsystem 204 by means of the transport message 598 that contains the alert message. The selection subsystem 204 then continues the transparent transport by transmitting the transport message 600 containing the alert message to the subscriber unit 100 via the forward link traffic channel. The alert message indicates that the subscriber unit 100 should start generating the tone of

P1412 / 98MX

-64i callback. If the call is answered, the GSM-MSC 106 transmits the connection message 602 to the interface A 206 BSC in accordance with the protocol of the interface A and the interface A 206 BSC responds by transmitting the transport message 604 containing the message of connection to selection subsystem 204. Selection subsystem 204 then continues to transparently broadcast the connect message to subscriber unit 100 by transmitting transport message 606 over the forward link traffic channel. Upon receipt of the transport message 606, the subscriber unit 100 stops generating the callback tone and transmits the transport message 610 containing the acknowledgment or acknowledgment of connection to the selection subsystem 204. The selection subsystem 204 responds by transparently issuing the acknowledgment or acknowledgment of connection to interface A 206 BSC by means of transport message 612 which then transmits the acknowledgment or acknowledgment message of connection 614 to the GSM-MSC 106, in accordance with the A GSM interface protocol. With the receipt of the acknowledgment message or acknowledgment of connection 614 by the GSM-MSC 106, a steady state call has been established.

Figure 8 is a message frequency diagram illustrating P1412 / 9BMX signaling messages

-65I exchanged during the release of the call originated from the subscriber unit made in accordance with an embodiment of the invention.

The release of the subscriber unit is the disconnection of a telephone call in response to the request for release by the subscriber unit 100 of the

Figure 2.

Release of the call originating from the subscriber unit begins during a phone call in process or other communication breaking the network connection when the subscriber unit

100 conveys transport message 652 that contains a reverse link traffic channel message. Selection subsystem 204 responds by issuing the disconnect message via the transport message

657 to interface A 206 BSC causing interface A 206 BSC to transmit disconnect message 672 to GSM-MSC 106 in accordance with the protocol of interface A. GSM-MSC 106 initiates the release of the network connection to the other departs and transmits release message 673 to interface A 206 BSC. In response, interface A 206 BSC transmits transport message 665 containing the release to selection subsystem 204. The selection subsystem 204 then issues the release by transmitting the transport message 658 to the

P1412 / 98MX

-66χ subscriber unit 100 through the direct link traffic channel.

Subscriber unit 100 responds by transmitting transport message 653 containing the complete release to selection subsystem 204 via the reverse link traffic channel. Selection subsystem 204 issues complete release by transmitting transport message 660 to interface A 206. Interface A BSC responds by issuing complete release message 676 to GSM-MSC 106 in accordance with protocol of interface A GSM. GSM-MSC 106 responds with the delete or clear 674 command to interface A 206 BSC, in accordance with the protocol of interface A GSM, which indicates that the two-way radio link must be released as well as the network resources of the interface A.

On receipt of the clear or clear command 674, the A 206 BSC interface generates a set of messages that cause the traffic channel interface to break. The breakdown of the traffic channel interface begins when interface A 206 BSC transmits the service disconnect message 668 BSC to selection subsystem 204. Additionally, interface A 206 BSC instructs switch 212 to remove the traffic channel connection between P1412 / 98MX processing system 210

-67i data and service options and GSM-MSC 106 (message is not displayed). The selection subsystem 204 acknowledges or acknowledges receipt of the BSS service disconnection request message 668 by transmitting the BSS service disconnection response 670 causing interface A 206 BSC to transmit the

<td>release</td><td>of the</td><td>link</td><td>of</td><td>radio</td><td colspan="2">BSS at</td><td>subsystem</td><td>of</td>

<td>selection</td><td> 204.</td><td>With the</td><td colspan="2">reception</td><td>of</td><td>the so</td><td>lawfulness 663</td><td>of</td>

<td>release</td><td>of the</td><td>link</td><td>of</td><td>radio</td><td>BSS</td><td>, the</td><td>subsystem</td><td>of</td>

<td>selection</td><td> 204</td><td>transmit</td><td>the</td><td>order</td><td>of</td><td colspan="2">release 651 a</td><td>the</td>

<td colspan="3">subscriber unit 100</td><td colspan="2">through</td><td>the</td><td>channel</td><td>of traffic</td><td>of</td>

direct link. Subscriber unit 100 responds by transmitting release command 650 to selection subsystem 204 via the reverse link traffic channel. The selection subsystem 204 then transmits the end forward traffic channel command 654 and the disconnect request 655 to the BTS 102. BTS 102 releases the resources used to process the forward and reverse link traffic channels and then transmits the end reverse link traffic channel 656 and the disconnect response 659 to the selection subsystem 204.

Selection subsystem 204 then transmits the release resource request 662 to BTS 102 and BTS 102 responds by transmitting response 661 from resource P1412 / 98MX

-68κ release to selection via reverse link traffic channel. Upon receipt of the response from the clearing resource, the selection subsystem 204 transmits the radio clearing response 664 to the interface A 206 BSC which responds by transmitting the call clearing request 666 to the selection subsystem 204. Selection subsystem 204 then transmits the call clear response to Interface A 206 BSC and releases the selection resources associated with the phone call. Interface A 206 BSC then transmits deallocation request 671 to call control processor 202 indicating that the selection and service resources associated with the phone call have been released and that they are available for processing other calls. Interface A 206 BSC also indicates that the call has been released to GSM-MSC 106 transmitting the clear or clear 675 in accordance with the interface protocol A GSM. Clear or Clear Complete 675 indicates to GSM-MSC 106 that call processing resources are currently available. Call control processor 202 responds to deallocation request 671 by transmitting deallocation response 667 to Inter face A 206 BSC. Upon receipt of deallocation response 667 by interface A 206 BSC, the call has been cleared.

P1412 / 98MX

-6969

Figure 9 is a message sequence diagram illustrating the signaling messages exchanged during the release of the network initiated call made in accordance with an embodiment of the invention. The release of the network initiated call is the disconnection of a phone call in response to a request originating from a system other than the subscriber unit * 100 of Figure 2. Release of the network initiated call begins during a phone call in process or during other communication. GSMMSC 106 initiates network outage by transmitting disconnect message 772 to interface A 206 BSC in accordance with the GSM interface interface protocol. Interface A 206 BSC responds by issuing transport message 757 containing the disconnect to selection subsystem 204 which issues transport message 753 which also contains disconnection to subscriber unit 100 via the direct link traffic channel. Subscriber unit 100 then transmits transport message 758 containing a release message to selection subsystem 204 which issues transport message 765 containing the release message to interface A 206 BSC in response. Interface A 206 BSC then transmits release message 773 to GSM-MSC 106 in accordance with the protocol of interface A GSM.

P1412 / 98MX

-70i

GSM-MSC 106 responds by transmitting the complete release message 776 to interface A 206 BSC in accordance with the protocol of interface A GSM. Interface A 206 BSC issues transport message 760 containing a release complete to selection subsystem 204 which responds by issuing transport message 752 which also contains complete release to subscriber unit 100 via the direct link traffic channel .

GSM-MSC 106 requests the release of the two-way radio link 'with the transmission of the clear or clear command 774 to interface A 206

BSC in accordance with the protocol of the GSM interface.

Upon receipt of the clear or clear command

774, the interface

A 206

BSC begins breaking the channel interface in accordance with the calling model

IS-95.

The breakdown of the channel interface begins when interface A 206

BSC transmits the service disconnection message

BSS to the selection subsystem

204.

Additionally, interface A 206

BSC instructs switch 212 to release the traffic channel connection between data processing and service options system 210 and the one shown).

The selection subsystem 204 acknowledges the receipt of the message 768 to request the disconnection of the

P1412 / 98MX

-7171 BSS service transmitting BSS service disconnect response 770, which causes interface A 206 BSC to transmit radio link release request 763 BSS to selection subsystem 204. Upon receipt of link release request 763 radio BSS, the selection subsystem 204 transmits the release command 751 to the subscriber unit 100 via the direct link traffic channel. Subscriber unit 100 responds by transmitting release command 750 to selection subsystem 204 via the reverse link traffic channel. Selection subsystem 204 then transmits command 754 of the end-end traffic channel and disconnect request 755 to BTS 102. The BTS 102 releases the resources used to process the forward and reverse link traffic channels and then transmits the end reverse link traffic channel 756 and the disconnect response 759 to the selection subsystem 204.

The selection subsystem 204 then transmits the request for the release resource 762 to the BTS 102 and the BTS 102 responds by transmitting the response 761 of the release resource to the selection via the reverse link traffic channel. Upon receipt of the release resource response, the selection subsystem 204 transmits the release response 764 of the

P1412 / 98MX

-7272 BSS radio link to interface A 206 BSC that responds by transmitting BSS call clearing request 766 to selection subsystem 204. Selection subsystem 204 then transmits BSS call clearing response 769 to interface A 206 BSC and releases the selection resources associated with the phone call that will be released. Interface A 206 BSC then transmits deallocation request 771 BSS to call control processor 202 indicating that the selection and service resources associated with the phone call have been released and are available for processing other calls. Interface A 206 BSC also indicates that the call has been released to GSM-MSC 106 by transmitting the clear or clear 775 in accordance with the Inter-A GSM protocol. Interface A BSC responds to deallocation request 771 BSS by transmitting deallocation response 767 BSS to interface A 206 BSC. Upon receipt of the 767 BSS deallocation response by interface A 206 BSC, the call has been cleared.

Figures 10A and 10B show a message sequence diagram illustrating signaling messages exchanged during subscriber unit registration performed in accordance with one embodiment of the invention. During registration of the P1412 / 98MX

-7373 subscriber unit, the subscriber unit 100 of Figure 2 notifies the GSM-MSC 106 of its location and present status so that the GSM-MSC 106 can provide the service to that subscriber unit 100. The registration of the subscriber unit begins with the channel request message 806 transmitted from the subscriber unit 100 to the BTS 102 via the reverse link access channel. In the preferred embodiment of the invention, channel request message 806 indicates that subscriber 100 is initiating a registration, however, this information may be provided in other messages in alternative embodiments of the invention. The BTS 102 responds to the channel request 806 by transmitting the BSS channel request 810 to Inter face A 206 BSC and the acknowledgment or acknowledgment message 808 BTS to the subscriber unit 100, although the transmission of the message

<td> 808</td><td colspan="2">acknowledgment or acknowledgment of receipt</td><td>BTS</td><td colspan="2">is optional in</td>

<td>the :</td><td>preferred modality of the</td><td>invention.</td><td>The</td><td>interface</td><td>A 206</td>

<td>BSC</td><td>responds by generating a</td><td>joint</td><td>of</td><td>messages</td><td>for</td>

<td colspan="2">establish an interface</td><td>signal</td><td>RF</td><td>modulated</td><td>CDMA</td>

bidirectional at subscriber unit 100 and BTS 102 transmitting BSS call setup request 812 to call control processor 202. Call control process 202 assigns a selector and a service to the call and indicates the result to the interface

P1412 / 98MX

-741

To 206 BSC in response 814 of BSS call installation. Upon receipt of the BSS call installation response 814, Inter face A 206 BSC transmits the selector call installation request 816 to the selection subsystem 204. The selector subsystem 204 responds by allocating a selection resource for processing the phone call and indicating this to the interface A 206 BSC with the answer 818 of the selector call installation. Upon receipt of the call setup response 818, Inter face A 206 BSC transmits the radio link setup request 819 to the selection subsystem 204. The selection subsystem 204 responds by transmitting the channel resource request 820 to the BTS 102.

Upon receipt of the channel resource request 820, the BTS 102 allocates channel processing resources to modulate and demodulate the forward and reverse link traffic channels associated with the phone call and transmit the message

822 response of the channel resource to the subsystem

The Selection Subsystem

204 responds connection request 824 to BTS 102 which responds by transmitting connection response 826 to selection subsystem 204.

The Selection Subsystem

204 then transmits null traffic data

828 , message 830 of traffic data from

P1412 / 9BMX

-751 start and null traffic data 832 to BTS 102. BTS 102 responds to start traffic data message 830 and null traffic data 832 by transmitting null traffic data 836 to subscriber unit 100 via the direct link traffic. The selection subsystem 204 also transmits the radio link resource message 834 to Inter face A 206 BSC. Upon receipt of the radio link resource message 834, interface A 206 BSC transmits the BTS channel assignment message 838 to the BTS 102 which responds by transmitting the channel assignment message 840 to the subscriber unit 100 via the direct link radiolocation. The subscriber unit 100 uses the assigned channel information contained in the channel allocation message 840 to process the data received through the assigned forward link traffic channel and transmits preamble 842 of the reverse link traffic channel so that the BTS 102 can acquire the reverse link traffic channel. Once the reverse link signal has been acquired, the BTS 102 transmits the start reverse link message 844 to the selection subsystem 204. The selection subsystem 204 responds by transmitting the reverse link acknowledgment or acknowledgment 846 to the unit Subscriber 100 through the direct link traffic channel. As indicated above, the

P1412 / 98MX

-761 messages such as acknowledgment or acknowledgment

846 reverse link exchanged between selection subsystem 204 and subscriber unit 100, passes through BTS 102 but is shown to be routed directly for ease of drawing. Additionally, the selection subsystem 204 transmits the radio link installation response 848 to Interface A 206 BSC. At this point, a bidirectional channel is established.

Subscriber unit 100 initiates the registration procedure by transmitting DTAP location update request 850 to selection subsystem 204. Selection subsystem 204 routes the location update request to Inter face A 206 BSC which initiates a SCCP connection to the GSM-MSC 106 as

<td>specify in</td><td>the</td><td>protocol</td><td>the</td><td>interface A</td><td colspan="2">GSM. Then</td>

<td>to store</td><td>the</td><td>information</td><td>of</td><td>the brand</td><td>of class,</td><td>the</td>

<td>interface A</td><td> 206</td><td>BSC generates</td><td>a</td><td>Message from</td><td>request</td><td>of</td>

<td>SCCP connection</td><td>than</td><td>contains the</td><td colspan="2">message 852</td><td>information</td><td>of</td>

three complete layers containing the location request

851 BSS. The full three layer information message 852 is part of the A GSM interface protocol and,

<td>by</td><td>so it's alright</td><td colspan="2">known</td><td colspan="2">in the technique</td><td>GSM-MSC</td>

<td> 106</td><td colspan="2">responds by transmitting</td><td>the</td><td>request</td><td>of</td><td>authentication</td>

<td> 853</td><td>to interface A</td><td> 206</td><td>BSC</td><td>which to</td><td>its</td><td>time issues the</td>

<td colspan="2">transport message</td><td> 854</td><td>than</td><td>contains</td><td>the</td><td>application</td>

P1412 / 98MX

-77s authentication to the selection subsystem 204. The selection subsystem then issues transport message 855 containing the authentication request to subscriber unit 100 via the direct link traffic channel. Subscriber unit 100 passes the transported authentication request to its GSM-based message processing portion that responds to authentication request 855 by transmitting transport authentication response 856 to the selector subsystem

204 using the reverse link traffic channel.

The selection subsystem 204 transparently issues the authentication response by transmitting transport message 857 to interface A 206 BSC. Interface A 206 BSC then transmits authentication response 858 to GSM-MSC 106 in accordance with the protocol of interface A GSM. GSM-MSC 106 responds by transmitting command 859 in encryption mode to interface A 206 BSC. Interface A 206 BSC then begins the encryption start procedures by transmitting command 860 in BSS cipher mode to selection subsystem 204 which transmits command 862 in cipher mode to subscriber unit 100 via the forward link traffic channel. After the processing of the command 862 in encryption mode, the subscriber unit 100 transmits the complete message 864 in encryption mode in encrypted form by means of the

P1412 / 98MX

-78i reverse link traffic channel to selection subsystem 204. Upon receipt of command 860 in BSS cipher mode, selection subsystem 204 begins encryption-decryption on all additional signaling and call data associated with the phone call. The selection subsystem 204 then transmits the complete message 866 in BSS cipher mode to interface A 206 BSC. The A 206 BSC interface responds by transmitting the full 868 command in encryption mode to the GSM-MSC 106 in accordance with the A GSM interface protocol.

The GSM-MSC 106 then transmits the request ID 874 to the interface A 206 BSC in accordance with the protocol of the GSM interface A, and the interface A 206 BSC responds by issuing the request ID through the transport message 872 to the selection subsystem 204. Selection subsystem 204 then transmits transport message 870 containing the request ID to subscriber unit 100 via the forward link traffic channel. The GSM-based message processing portion of subscriber unit 100 responds by generating an ID response and subscriber unit 100 transmits that ID response within transport message 880 to selection subsystem 204 via the reverse link traffic channel. The 204 P1412 / 98MX Selection Subsystem

-79ι then issues the ID response by transmitting transport message 878 to interface A 206 BSC, which responds by issuing ID response 876 to GSM-MSC 106 in accordance with the Inter-A GSM protocol. GSM-MSC 106 receives response ID 876 and transmits the accepted location update 882 to interface A 206 BSC in accordance with the protocol of interface A GSM. An interface A 206 BSC then transmits transport message 886 containing the accepted location update to selection subsystem 204, which responds by issuing the accepted location update to subscriber unit 100, transmitting transport message 890 via the direct link traffic. Subscriber unit 100 responds by transmitting transport message 891 containing a temporary mobile subscriber identity reassignment (TMSI) command to selection subsystem 204 and selection subsystem 204 then transmits transport message 892 containing the Transport TMSI reassignment command to Inter face A 206 BSC. Interface A 206 BSC responds by transmitting TMSI remap command 894 to GSM-MSC 106 in accordance with the A GSM interface protocol. On receipt of the 894 TMSI reassignment command, the GSM-MSC 106 transmits the clear or clear command 896 to interface A 206.

P1412 / 98MX

-8080

BSC to initiate the release of the radio link.

<td colspan="3">Referring now to the Figure</td><td>10B,</td><td>continues</td>

<td>with illustration of</td><td>the</td><td>messages</td><td>of</td><td>signaling</td>

<td>exchanged during</td><td>the</td><td>registry</td><td>of</td><td>unit</td>

<td>effected subscriber of</td><td colspan="2">conformity with</td><td>a</td><td>modality of</td>

The invention, Interface A 206 BSC transmits radio link BSS request 902 release to selection subsystem 204 after receiving clear or clear command 896. Upon receipt of radio link release request 902 BSS, the selection subsystem 204 transmits the release command 900 to the subscriber unit 100 via the direct link traffic channel. Subscriber unit 100 responds by transmitting release command 904 to selection subsystem 204 via the reverse link traffic channel. Selection subsystem 204 then transmits command 906 of the end-end traffic channel and disconnect request 908 to BTS 102. The BTS 102 releases the resources used to process the forward and reverse link traffic channels and then transmits the end reverse link traffic channel indication 908 and the disconnect response 910 to the selection subsystem 204. The selection subsystem 204 transmits request 914 for release resource to BTS 102 and BTS 102 responds by transmitting response 916 of resource

P1412 / 98MX

-81Ε release. On receipt of the response 916 from the release facility, the selection subsystem 204 transmits the BSS radio release response 918 to the responding interface A 206 BSC by transmitting the BSS call release request 920 to the selection subsystem 204. The Selection subsystem 204 then transmits BSS call release response 922 to interface A 206 BSC and releases selection resources associated with the phone call. Interface A 206 BSC transmits BSS deallocation request 924 to call control processor 202 indicating that the selection and service resources associated with the phone call have been freed and are available for processing other calls. In addition, interface A 206 BSC indicates to GSMMSC 106 that the call has been released by transmitting the clear or clear 926 in accordance with the protocol of interface A GSM. Call control processor 202 responds to BSS deallocation request 924 by transmitting BSS deallocation response 928 to interface A 206 BSC. When the deallocation response 928 is received by Inter face A 206 BSC, the location update procedure is completed.

Upon initiating the call and registration of the subscriber unit by first establishing an on-air CDMA interface between the subscriber unit 100 P1412 / 9BMX

-82i and BSS 105, and then establishing a network telecommunication network connection between subscriber unit 100 and GSM-MSC 106 by transmitting signaling messages via those forward and reverse link traffic channels, makes possible the use of a wireless telecommunications system that uses a CDMA over-the-air interface in conjunction with the A GSM interface protocol. The ability to provide CDMA over the interface in conjunction with the A GSM interface network is also possible through the use of an A BSC interface that receives messages from the A GSM interface and examines those messages from the A GSM interface and in response performs various actions. These actions include converting the signaling message from the A GSM interface to an internal BSS protocol and determining the appropriate response to each message based on the configuration and capabilities of the CDMA over-the-air interface. Appropriate responses include allocation of signal processing resources in response to an allocation request. The ability to provide CDMA over the interface in conjunction with the GSM A-interface network is also facilitated by the use of a selector element that detects when encryption messages are transmitted and subsequently begins the encryption process. This allows the

P1412 / 98MX

-8383 encryption feature of the inter-face A GSM network is provided together with the soft-transfer feature of the IS-95 over-the-air protocol.

Figure 11 is a block diagram of the A 206 BSC interface when configured in accordance with an embodiment of the invention. The 990 message generation and processing system, the SS7 992 stack interface, and the BSC 994 packet interface are coupled by the local busbar 996. During operation, the SS7 992 stack interface passes the signaling messages transmitted from conformity with GSM interface A with GSM-MSC 106. The SS7 992 stack interface also passes the data associated with the signaling messages to the 990 message processing and generation system. Additionally, the 990 message processing and generation system exchanges signaling messages with the BSC 994 packet interface via the local bus bar 996. The BSC 994 packet interface responds by placing the received signaling message data into BSS network packets and extracting the signaling message data from the BSS network packets and providing the data to the 990 message processing and generation system. The system processing and message generation 990 performs various message determination and message generation functions

Ρ1412 / 9ΘΜΧ

-8484 signaling message from an A 206 BSC interface as described above in response to the received signaling message data. The message generation and processing system 990, the SS7 992 interface stack and the BSC 994 packet interface are each comprised of a semiconductor-based microprocessor and a memory storage system in the preferred embodiment of the invention, although a single microprocessor and memory system with sufficient processing power could be used to implement any two or all three of these systems in alternative embodiments of the invention.

FIG. 12 is a block diagram of a subscriber unit 100 when configured in accordance with an embodiment of the invention. The forward link RF signals transmitted from a BTS 102 (Figure 3) are received by antenna 980 and passed to RF processing system 982. RF processing system 982 converts the signals to the baseband and digitizes the band signals base. The digital signal processing system 984 processes the digitized baseband signals in accordance with the CDMA protocol used to process the signals in the transmission. As indicated above, the CDMA protocol used in the preferred embodiment of the invention is that which is P1412 / 98MX

-85i associated with the IS-95 protocol physical signal modulation techniques, although the use of other CDMA protocols is consistent with the operation of the present invention. The signal processing performed by the 984 digital signal processing system includes demodulation with the forward link scatter code and channel code, as well as Viterbi decoding and block disintegration, the use of which is well known in technique. This processing is done on a frame-by-frame basis. The frames resulting from the digital data from the digital signal processing system 984 are passed to the control system 986. The control system 986 receives the digital data frames and determines whether the digital data is a signaling message or user data based on the information of the guide or head contained in each box. The user data is passed to the input-output system 988 which normally converts the user data into audio information but which can also provide the user data in digital form for further processing by other digital systems. The signaling data is assembled into signaling messages which are further categorized or hierarchized by the control system 986 in the transport signaling messages or in the local signaling messages by examining the

P1412 / 98MX

-86i

<td>bits</td><td>as guide</td><td>or head</td><td>of</td><td>the</td><td>messages.</td><td></td><td></td>

<td></td><td>A</td><td>message</td><td>not</td><td>of</td><td>transportation or</td><td>of</td><td>signaling</td>

<td>local</td><td>pass</td><td colspan="2">to control</td><td>of</td><td>interface 987</td><td>than</td><td>processes the</td>

message and generates some appropriate response. The appropriate response includes configuring the 986 digital signal processing system for receiving and transmitting baseband digital signals by providing the necessary channel codes and dispersion as well as generating outgoing signaling messages that are transmitted to BTS 102 of Figure 4 by a non-transport frame in accordance with the various call processing procedures described above.

Transport signaling messages pass to network control 989, which is referred to as the GSM message processing portion of subscriber unit 100. Network control 989 processes the local signaling message and *

generates an appropriate response that may include the generation of outgoing signaling messages in accordance with the various call processing procedures described above. The output signaling messages generated by the control

<td colspan="2">network 989</td><td>are placed</td><td>in</td><td>messages</td><td colspan="2">transport by</td><td>the</td>

<td>system</td><td>of</td><td>control 986</td><td>and</td><td colspan="2">are issued</td><td>With</td><td>the</td>

<td>messages</td><td>of</td><td>signaling</td><td>of</td><td>departure</td><td>since</td><td>the control</td><td>of</td>

P1412 / 98MX

-8787 interface 987 to the 984 digital signal processing system that performs Viterbi encoding, block interleaving, modulates and disperses data in accordance with CDMA signal processing techniques. The data processed in CDMA is passed to the RF signal processing system 982 which generates a reverse link RF signal by phase quadrature shift manipulation (QPSK) using digital data in accordance with IS-95 which is transmitted to a ΒΤΞ 102 of FIGURE 4.

In the preferred embodiment of the invention, the digital signal processing system 984 is comprised of a digital signal processor (DSP) controlled by the software stored in the memory system (not shown). Additionally, control system 986 is comprised of a microprocessor also controlled by software instructions stored in a memory system (not shown). Portions of the software instructions used to control the microprocessor are used to implement interface control 987 and network control 989. In alternative embodiments of the invention, control system 986 and digital signal processing system 984 can be implemented through the use of one or more integrated circuits designed for the client, where the

P1412 / 98MX ι

989 network control and interface control are a portion of the integrated circuits used to implement control system 986. Additionally, while in the configuration shown, control system 986 is coupled between input system output 988 and the 984 digital signal processing system. In the alternative embodiments of the invention, each of these three systems can be coupled by using the mutually shared main data bar. Additionally, the control system 986 and the digital signal processing system 984 can share the use of the same memory system via the shared main data bar or by placing them on the same integrated circuit.

Thus, a method and apparatus for providing wireless telecommunication service using CDMA over the interface and a GSM communications network were described. The previous description of the preferred embodiments is provided to allow any person skilled in the art to prepare or use the present invention. The various modifications to these modalities will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other modalities without the use of inventive power. Of this P1412 / 98MX

-8989

<td>so no</td><td>I know</td><td>pretends that</td><td>the</td><td>Present</td><td>invention be</td>

<td>limited to</td><td>the</td><td>modalities</td><td colspan="2">shown in</td><td>the present but</td>

<td>That this</td><td>of</td><td>accordance</td><td>with</td><td colspan="2">the widest scope</td>

<td>consistent</td><td>with</td><td colspan="2">the principles and</td><td>novel</td><td>particularities</td>

<td colspan="2">revealed in the</td><td>Present.</td><td></td><td></td><td></td>

Ρ1412 / 98ΜΧ

-90Ε