Wireless channel allocation in a base station processor

(12) PATENT

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NORWAY (19) NO (11) 338397 (51) IntCI.

H04W 72/12 (2009.01)

H04W 72/00 (2009.01) (13) B1

NIPO

<td> (21)</td><td>Appln</td><td> 20092029</td><td>(86) Entering day and</td><td> 2001.05.04</td>

<td></td><td></td><td></td><td>Appln</td><td>PCT / US2001 / 14642</td>

<td> (22)</td><td>Inng.dag</td><td> 2009.05.26</td><td>(85) Continuation Day</td><td> 2009.05.26</td>

<td> (24)</td><td>Løpedag</td><td> 2001.05.04</td><td>(30) Priority</td><td>2000.05.05, US 09 / 565,095</td>

<td> (41)</td><td>Alm.tilgj</td><td> 2002.12.30</td><td></td><td></td>

<td> (45)</td><td>communicated</td><td> 2016.08.15</td><td></td><td></td>

<td> (62)</td><td>Divided from</td><td>20025305, with date 2002.11.05</td><td></td><td></td>

<td> (73)</td><td>proprietor</td><td colspan="3">IPR Licensing Inc, 300 Delaware Avenue, Suite 527, US-DE19801 WILMINGTON, USA</td>

<td> (72)</td><td>Inventor</td><td colspan="3">James A Proctor Jr., 440 Mosswood Boulevard, US-FL32903-4007 INDIALANTIC, USA Kevin L Farley, 350 Viking Street North East, US-FL32907 PALM BAY, USA</td>

<td> (74)</td><td>Fullmektig</td><td colspan="2">Bryn Aarflot A S, PO Box 449 Center, 0104 OSLO, Norway</td><td></td>

<td> (54)</td><td>Designation</td><td>Assigning wireless channels in a base station processor</td>

<td> (56)</td><td>cited</td><td></td>

<td></td><td>publications</td><td>WO 9837706 A2 US 5590133 A</td>

<td> (57)</td><td>Summary</td><td></td>

A method of assigning channels for messages is provided. The method at least comprising the steps of determining a message type received from a sender, provided that a return message is expected based on message type to determine a latency period, and to assign a channel for receiving the return message at a time determined by the latency period.

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FIELD OF THE INVENTION

The present invention relates to a method for complex resource allocation within communication systems, more particularly the invention includes a method for assigning communication channels within communication networks.

BACKGROUND OF THE INVENTION

Infrastructure equipment for wireless networks is increasingly being used to enable computing devices to communicate over a wireless medium with a wired network, such as the Internet. In a wireless data network, a number of local computing devices, such as PCs, are supported via wireless subscriber access devices. A subscriber access device provides a wireless radio connection to a base station processor. The base station processor is also connected to an internet port which provides a connection to a wiring network. Like a mobile telephone network, the base station processor assigns a number of wireless channels as needed to provide message transmission to and from the subscriber units. The wireless channels are assigned to messages sent and received from the subscriber unit on behalf of the local computing device.

In a typical base station processor, the wireless channels are a scarce resource shared by the subscriber units. Messages are often queued pending an available channel. Wiring also typically uses techniques to detect the speed at which a receiver processes messages. These techniques reduce queue formation by preventing a receiver overload by reducing the rate at which messages are sent, and consequently reduce throughput. Such techniques can interpret the queue generation of messages by the base station processor as a constraint in the wiring network, and consequently reduce throughput. The protocols used in the wiring network are not very suitable for efficient communication over wireless connections.

In a TCP / IP network, e.g. applied blocking control techniques such as slow start, barrier avoidance, fast retransmission and fast recovery. According to the slow start technique, which is defined in the internet

RFC 2581, an acknowledgment message (ack) is expected as a feedback to each message sent. The number of bytes or messages sent is gradually increased as the receipts are received in a timely manner. If the receipt is not received in a timely manner, further messages will be sent less frequently to reduce throughput. However, the queue generation of messages at the base station processor does not indicate a lock at the base station processor. Instead, the queue formation indicates the propagation delay inherent in wireless networks. However, this propagation delay is interpreted as blocking by the wiring protocols, such as TCP / IP.

Therefore, it would be advantageous to provide a method and apparatus capable of anticipating the arrival of the return message and allocating a channel to be available to transmit the message through the base station processor so that the throughput of the wireless network is not reduced by the blocking control properties of the protocol in the wiring network. , such as slow start.

WO 9837706 A2 describes resource allocation between a central access point or base unit of a mobile device requesting a service. The base unit allocates resources among competing mobile devices that perform a variety of applications. A complex plan is generated to achieve an optimal allocation that provides the highest quality of services to the mobile devices. Complexity is reduced by communicating the complex plan of available uplink resources in a downlink transmission so that the mobile device is free to transfer its data on an uplink transmission regardless of downlink transmission.

US 5590133 A discloses a general packet data connection control between a base station and a mobile station using a timer and / or timer in inactivity. One or more packet data channels formed between the communication terminals are used for transmission of various data services.

SUMMARY OF THE INVENTION

In a first aspect, the present invention relates to a wireless base station comprising circuitry configured to communicate IP protocol data with a subscriber access unit, wherein the circuitry is further configured to send information to the subscriber access unit indicating a first period of time from a set of subscriber access unit time periods to wait. on receiving a downlink from the wireless base station, where the circuitry is further configured to send downlink IP data to the subscriber access unit in response to the expiration of the first time period, and the circuitry is further configured to send information to the subscriber access unit indicating a second time period from a set of subscriber access unit time periods to wait for to receive a downlink from the wireless base station, where the circuitry is further configured to send downlink IPdata to the subscriber access unit in response to the trigger of the second time period.

In a second aspect, the present invention relates to a wireless subscriber access unit comprising circuitry configured to communicate IP protocol data with a base station, the circuitry further configured to receive information from the base station indicating a first time period from a set of time periods for a wireless subscriber access device to wait. on receiving a downlink from the base station, wherein the circuitry is further configured to receive downlink IP data from the base station in response to the expiration of the first time period, and the circuitry is further configured to receive information from the base station indicating a second time period from a set of time periods for the wireless subscriber access device to waiting to receive a downlink from the base station, where the circuitry is further configured to receive downlink IP data from the base station in response to the expiration of the second time period.

Further embodiments of the invention are set forth in claims 2 - 7, 9 and

10.

A method of assigning channels in a communication system is described to support the transmission of messages between a subscriber and a base station processor. More specifically, the method comprises the steps of determining a message type received from a sender, provided that a return message is expected based on message type to determine a latency period, and to assign a channel for receiving the return message at a time determined by the latency period.

A latency period is determined corresponding to the timing of a return message that is expected from a response node in response to an outgoing message sent from a transmitter via the base station processor. A latency controller in the base station processor calculates the latency period and stores the latency period in an allocation table. A management program allocates a channel prior to receiving the return message, which should be available at the end of the latency period indicated in the allocation table. At approximately the end of the latency period, the return message is received and the management program assigns a channel as defined in the allocation channel. The assigned channel is used to send the return message to or from the corresponding subscriber.

The latency control device calculates the latency period using a variety of transmission parameters defined in the wiring network protocol. In a TCP / IP network, e.g. the transmission parameters used to calculate the latency period include window size, available window space, average message size, number of pending receipts, message type, number of messages received in session, number of pending receipts, maximum number of pending receipts, and other transmission parameters.

Other advantageous embodiments of the present invention will be apparent from the appended independent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features and advantages of the invention will become apparent from the following more specific description of preferred embodiments of the invention, as illustrated in the accompanying drawings, in which like reference numerals refer to the same parts of the various figures. The drawings are not necessarily to scale, since instead the emphasis is on illustrating the principles behind the invention.

Fig. 1 is a block diagram of a communication system suitable for performing wireless channel assignment as defined herein; 2 shows a base station processor in communication with a plurality of subscriber access units; FIG. 3a shows message transmission in the system of FIG. 2, FIG. 3b shows a channel assignment table corresponding to the messages of FIG. 3a, fig. 4 is a flow chart of channel assignment as defined herein; FIG. 5a shows a web page fetch using the system of FIG. 1, FIG. 5b shows the allocation table corresponding to the messages of FIG. 5a, fig. 5c shows a time schedule corresponding to the assignment table of FIG. 5b, and FIG. 6 shows a subscriber profile table for channel assignment as defined herein.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a block diagram of a communication system 10 adapted for channel assignment in a wireless network as defined herein. The communication system includes a local computing device, such as a PC 12, a subscriber access unit 14, a base station processor 16 and an internet port 18. The PC 12 is in communication with the subscriber 14 via a wired connection 20. The subscriber 14 is in communication with a base station processor 16 via a wireless connection 26. The base station processor is in communication with an Internet port 18 via the wired connection 24. The Internet port 18 is arranged for communication via a public access network, such as the Internet.

The PC 12 may therefore be provided access to the network server 18, which may be a remote device placed on the Internet or another network through a combination of the provided wiring 20, 24 and the wireless connection 26. The wiring 20, 24 is typically supported by a protocol such as TCP / IP or UDP. The wireless connection is supported by protocols, such as the protocol described in an undecided US patent application entitled Dynamic Frame Size Settings for Multichannel Transmission, published as PCT Application No. WO 99/44341, September 2, 1999. The PC 12 typically delivers an Internet Protocol Packet (IP packet) to the subscriber 14 over the wired connection 20, such as e.g. may be an Ethernet type connection. Subscriber 14 removes the frame of the IP packet and transmits the data in the IP packet to the base station processor 16 over the wireless connection 26 according to a wireless connection protocol. The base station processor 16 extracts the wireless connection frames and sends them in the form of IP packets over the wireless connection 24 to the internet port 18. The subscriber 14 and the base station processor 16 are therefore considered as endpoints for the wireless connection 20.

Referring to FIG. 2 wherein the base station processor 16 is shown in more detail. The base station processor 16 is in communication with a number of subscribers 14a14d. Additional subscriber units 14 (x) may be provided. Subscribers communicate with the base station processor via wireless channels 22a-22j as shown. Additional channels 22 (x) may be added. As indicated above, channels 22 are used to transmit messages to and from subscribers 14. A control program 28 assigns the channels 22 on demand and assigns available channels to messages transmitted between the subscribers 14 and the base station processor 16.

The channels 22 are one-way between the subscribers 14 and the switch 16, however, several channels may be assigned to messages originating or intended for a particular subscriber 14. In the example shown, channel 22a is assigned to send a message from the base station processor 16 to the subscriber 14b. Channel 22b is assigned to receive a message at base station processor 16 from subscriber 14c, while channel 22c is assigned to send a message to subscriber 14c. Channels 22d and 22e are assigned to send a message to subscriber 14d, and channel 22f is assigned to receive a message from subscriber 14d. As indicated above, the management program typically assigns channels quickly to the subscribers to accommodate channel requests for messages to be sent to and received from the subscribers 14.

Two designated channels that are common to all subscribers 14 are used to initiate message traffic on a channel. A common access channel 30 is used by a subscriber 14 to request a channel from the base station processor 16. A common search channel 32 is used to notify a subscriber 14 that it is being assigned a channel. The messages are then forwarded by the subscribers 14 to the PC 12 or to the base station processor 16, depending on the direction.

The base station processor 16 also includes a latency control device 34 for determining latency delays, and an allocation table 36, both of which are described in more detail below. In a typical message transmission, as indicated above, a number of latency delays occur between the message transmitter and the recipient, or the response node. For example, a wireless propagation delay occurs. by transmitting a message from the base station processor 16 to the subscriber 14 (FIG. 1). A network propagation delay occurs when a message is sent over the Internet or another network with public access. Other latency delays are present, as explained in more detail below. It is common in a protocol such as TCP / IP to expect a return message, typically a receipt, in response to a message sent to a reply node. In accordance with the invention, as defined herein, the latency controller is included in the base station processor for calculating the latency delay and scheduling a channel accordingly. Channel assignment refers to messages sent from a transmitter in one direction or another; the return message will be sent back to the sender of the node receiving the message. Therefore, a channel assignment for a return message will be predictively scheduled when a message is sent to or from the subscribers 14.

Referring to FIG. 3a and 3b, illustrating a more detailed configuration of the base station processor 16, including the latency controller 34, the allocation table 36, and the control program 28. The latency controller 34 is a process that calculates the latency delay associated with the return message sent by a response node 40 Assignment Table 36 is a storage structure which stores an entry 38a, 38b for each channel assignment 22b, 22c, and associated latency times T_o and Το + Ή. A control program 28 is a process that reads the allocation table 36 and the latency information to determine the allocation of channels to expected messages.

In a typical message transmission, the PC 12 sends a connection request message to a reply node 40, as indicated by the arrow 42. The message 42 is sent at time T_o. Accordingly, an entry 38a is written into the allocation table 36 of the assigned channel 22b with subscriber 14c at time T_o. When the message 42 is received through the channel 22b, the latency control device 34 examines the message.

The latency controller 34 determines that the message type is a request for a TCP / IP connection and that a receipt can therefore be expected as a return message.

The latency controller 34 determines the latency period that will elapse before receiving the return message by the base station processor 16. The latency controller 34 determines e.g. that an ISP delay (ISP = Internet Service Provider, Internet service provider) 44 will occur between Internet port 18 and Internet 50, as indicated by an Δ / Π; in addition, a network propagation delay 46 will occur when the message 42 is transmitted over the internet 50, as indicated by ΔΤ₂; and then a response node delay 48 will occur while the reply node 40 processes the message and sends the return message, as indicated by Δ T₃. The latency period T_L 52 is therefore calculated by the latency control device to be T_L = Δ Ti + Δ T₂ + Δ T₃. The latency controller then writes an entry 38b into the allocation table 36 to indicate that after the latency period, a return message 54 can be expected from the reply node 40 to the subscriber 14c.

Channel 22c is accordingly assigned at time T_o + T_L for subscriber 14c. The return message 54 is sent by the response node 40 and received by the base station processor 16 at time T_o + T_L. According to the allocation table 36, the control program 28 assigns channel 22c to send the return message 54 to the subscriber 14c.

In alternative embodiments, the channels are scheduled as a general collection in the allocation table and are not assigned to a particular subscriber until the return message is truly received.

In the example above, the latency controller 34 calculates the latency period T_L 52 based on the message type and the corresponding expected return message. Many protocols, including the TCP / IP protocol, specify not only the return message, but also other transmission parameters. Therefore, the way to determine the latency delay depends on a number of factors that depend on the protocol used. In a TCP / IP protocol, such factors may include transfer parameters such as window size, window available space, average message size, number of outstanding receipts, message type, number of messages received in the session, number of outstanding receipts, maximum number of outstanding receipts and other transfer parameters.

For example, TCP / IP uses a sliding window as a performance enhancing feature, as defined in Internet RFC 1323. Such features can be used in conjunction with the transfer parameters to improve performance through a base station processor, as defined herein.

A TCP / IP network can operate in accordance with the sliding window protocol in an effort to provide a reliable delivery stream while maximizing bandwidth. According to this protocol, both endpoints of a TCP / IP connection convey an acceptable window size. The window size indicates a maximum number of bytes that can be transmitted by a transmitter unit before receiving a receipt from the receiver unit. The window is generally referred to by a maximum number of packages that are not acknowledged. When the transmitter unit receives a receipt for the first packet in the window, it lets the window slip and sends the next packet.

In the message 42 sent in the example of FIG. 3a, the latency control device examines the TCP / IP packet in a non-destructive manner to determine the message type. Other aspects of the TCP / IP packet, as summarized above, can also be examined to provide transmission parameters and to use these parameters to determine the latency period 52 associated with the return message. In the examples which follow in FIG. 4 and 5a-5c further include the latency control device 34 a subscriber profile table 56 for storing transmission parameters corresponding to each of the subscribers 14.

Referring to the flow chart outlined in FIG. 4 together with the system diagram of FIG. 3a, where a message is received by the base station processor 16, as shown in step 100. The latency controller 34 examines the TCP / IP packet information as described in step 102. A lookup is performed in the subscriber profile table to find the entry corresponding to the subscriber , as outlined in step 104. The corresponding transfer parameters are obtained, as shown in step 106. The transmission parameters are updated to reflect the TCP / IP packet information examined in step 102, as described in step 108. A determination is made to indicate whether a return message is expected to complete the message, as outlined in step 110. If no return message is expected, the message is sent as shown at step 120, and the control returns to step 100 until the next message is received, as described in step 122. If a return message is expected, the latency controller 34 calculates the latency period 52 using the subscriber transfer parameters updated in step 108, as described in step 112. A new entry corresponding to the calculated latency period 52 is stored in the allocation table 36, as shown. in step 114. The message is then sent to the reply node 40, as outlined in step 116. The control is transmitted back to step 118 until the next message is received.

In FIG. 5a-5c is another embodiment of the message transmission sequence of FIG. 3b shown in more detail. A connection request 42 is sent to the PC 12 at time T_o. The latency controller 34 examines the packet information and determines the subscriber 14d. The latency controller looks up subscriber transfer parameters 14d in subscriber profile table 56, and updates the parameters accordingly to match the new packet information. The latency controller 34 determines that a connection acknowledgment message 54 is expected as a return message. The latency controller 34 calculates the latency delays Δ Τι, Δ T₂ and Δ T₃ as a result of the updated transfer parameters, and calculates the latency period T_A as the result T_A = Δ Ti + Δ T₂ + Δ T3.

The latency controller 34 stores the entry 58 in the allocation table 36 to inform the control program to assign channel 22d to subscriber 14d at time T_A, as indicated in schedule 86 for introduction 68.

The response node 40 then sends the return message 54. The base station processor 16 receives the return message 54, and the latency controller 34 examines the packet information. The latency controller looks up subscriber transfer parameters 14d in subscriber profile table 56, and updates the entry accordingly. The latency controller 34 determines that the return message type is a connection response acknowledgment and that a request message is likely to be sent from the PC as a return message.

When the message is sent to the subscriber 14d, the latency period is compared as follows. The wireless propagation time Δ T₄ indicates the latency assigned to transmission over the wireless connection 26 between the base station processor 16 and the subscriber 14d. Subscriber response time Δ T₅indicates the latency assigned to transmission over line 20 between subscriber 14d and PC 12. Latency controller 34 accordingly uses the subscriber profile table to calculate the latency period Δ T_B from Δ T₄+ Δ T₅.

A corresponding entry 60 is entered in the allocation table 36 to inform the control program of assigning channel 22f to subscriber 14d at time T_B, as indicated in schedule 86 at insertion 70.

The PC 12 sends an HTTP retrieval message 78 after receiving the receipt 54. The corresponding transmission parameters are looked up in the subscriber profile table 56 and updated accordingly to match the message 78. As a result of the updated transmission parameters, the latency control device 78 determines that an HTTP retrieval receipt 80 and an HTTP data message 82 are likely to be sent as return messages at the same time. The latency controller accordingly calculates the latency period T_c from T_c = Δ Ή + Δ T₂ + Δ T₃, and enter two entries in the assignment table 36. The entry 62 assigns channel 22d and the entry 64 assigns channel

22e to subscriber 14d at time T_c, as indicated by entries 72 and 74 of time schedule 86.

When the HTTP data message is received at the switch 16, the latency controller 34 determines that an HTTP data receipt 84 is the return message, and enters the input 66 to assign channel 22f at T_D = Δ T₄ + Δ T₅, as shown by entry 76 in the time schedule 86.

An example of the subscriber profile table 56 is shown in FIG. 6. Each entry 86 is adapted to store transmission parameters 88 corresponding to the messages received by a particular subscriber 14. Such parameters include window size, available window space, average message size, number of outstanding receipts, message type, number of messages received in the session. , the number of outstanding receipts and the maximum number of outstanding receipts. Other parameters may be specified as defined in the TCP / IP protocol or another protocol used by the base station processor.

Those skilled in the art will readily recognize that the programs defining the operations and methods mentioned herein may be provided to the base station processor in many forms, including but not limited to: a) information permanently stored on an unwritable storage medium such as ROM (b) changeable information stored on recordable storage media such as floppy disks, magnetic tapes, CDs, RAM devices, and other magnetic and optical media; or c) information conveyed to a computer through communication media, e.g. by using baseband or broadband signaling techniques such as in electronic networks such as the Internet or telephone modem lines. The operations and procedures may be implemented in software that can be executed from a repository using a processor. Alternatively, the operations and methods may be fully or partially designed using hardware components, such as special integrated application circuits (ASICs), state machines, controllers or other hardware components or devices, or a combination of hardware and software components.

Although the invention has been specifically shown and described with reference to preferred embodiments, those skilled in the art will appreciate that various changes in shape and detail may be made without departing from the scope of the invention as set forth in the appended claims. Accordingly, the present invention is not limited to anything other than the following claims.