Control signaling and dynamic channel allocation in a wireless network

• US 7,519,043 B2
• Filed: 05/27/2004
• Issued: 04/14/2009
• Est. Priority Date: 06/11/1999
• Status: Expired due to Fees

• Current Assignee: Axxcelera Broadband Wireless, Inc. (Moseley Wireless Solutions Group)
• Original Assignee: Axxcelera Broadband Wireless, Inc. (Moseley Wireless Solutions Group)
• Inventors: Porter, John David, Vester, Walter Charles, Freeman, Benedict Russell
• Primary Examiner(s): HO, DUC CHI
• Application Number:
  US10/854,151
• Publication Number:
  US 20040218563A1
• Time in Patent Office: 1,783 Days
• Field of Search: None
• US Class Current: 370/347
• CPC Class Codes: H04L 2012/5607 Radio
• CPC Class Codes: H04L 2012/5625 Operations, administration and maintenance [OAM]
• CPC Class Codes: H04L 2012/563 Signalling, e.g. protocols, reference model
• CPC Class Codes: H04L 2012/5672 Multiplexing, e.g. coding, scrambling
• CPC Class Codes: H04W 16/04 Traffic adaptive resource partitioning
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 16/12 Fixed resource partitioning
• CPC Class Codes: H04W 16/24 Cell structures
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 8/24 Transfer of terminal data

Abstract

A dynamic channel allocation method and system for use in a wireless network operates by monitoring at least the allocated channel allocated to a particular network node to generate one or more channel metrics relating to radio conditions on the channel. The metrics generated are Received signal power, signal to noise ratio of transmissions on the network and long-term mean square of the equaliser error used in each terminal. The generated metrics are communicated back to the cell access point or the network control server over a signalling channel, and a new frequency is allocated to the cell if it is determined from the metrics that the presently allocated channel is suffering interference. The signalling channel is preferably an ATM VPI/VCI pair, such that signalling messages are transmitted as ATM cells which can be communicated across the wireless channel using the sane signalling frame as is used for payload cells.

Claims

1. A method of signalling network control messages for use in a packet-switched wireless data network geographically arranged into one or more cells, each cell comprising one or more fixed base stations and a plurality of subscriber terminals arranged in a point-multipoint manner, communications between the base station and subscriber terminals in each cell being performed on a time division multiple access (TDMA) basis, the method being characterized by comprising the steps of:

defining a signalling frame for time division duplex transmission of all data packets between the base station and subscriber terminals, wherein said data packets are Asynchronous Transfer Mode (ATM) cells;

transmitting the data packets within the defined signalling frame across a first ATM VPI/VCI pair; and

transmitting the network control messages as data packets within the defined signalling frame across a second ATM VPI/VCI pair.

2. A method according to claim 1, wherein the ATM cells containing the network control messages are assigned the same VPI/VCI addresses throughout the network, such that the network control messages are sent across a dedicated VPI/VCI pair.

3. A method according to claim 2, wherein the dedicated VPI/VCI pair is permanently available.

4. A method according to claim 1, wherein the network control messages are packetised into Internet Protocol (IP) datagrams, the IP datagrams being subsequently packetised into ATM cells for transmission across the network.

5. A method according to claim 1, wherein the network is further provided with network control servers, network control messages being passed between any of the network control servers, fixed base stations and subscriber terminals.

6. A method according to claim 5, wherein the network control messages relate to the transmission frequency at which base stations and subscriber terminals should transmit in each cell.

7. A system for signalling network control messages for use in a packet-switched wireless data network geographically arranged into one or more cells, each cell comprising one or more fixed base stations and a plurality of subscriber terminals arranged in a point-multipoint manner, communications between the base stations and subscriber terminals in each cell being performed on a time division multiple access (TDMA) basis, the system being characterized by comprising:

means for defining a signalling frame for time division duplex transmission of all data packets between the base station and subscriber terminals, wherein said data packets are Asynchronous Transfer Mode (ATM) cells;

means for transmitting the data packets across a first ATM VPI/VCI pair; and

means for transmitting the network control messages as data packets within the defined signalling frame across a second ATM VPI/VCI pair.

8. A system according to claim 7, wherein the ATM cells containing the network control messages are assigned the same VPI/VCI addresses throughout the network, such that the network control messages are sent across a dedicated VPI/VCI pair.

9. A system according to claim 8, wherein the dedicated VPI/VCI pair is permanently available.

10. A system according to claim 7, wherein the network control messages are packetised into Internet Protocol (IP) datagrams, the IP datagrams being subsequently packetised into ATM cells for transmission across the network.

11. A system according to claim 7, wherein the network is further provided with network control servers, network control messages being passed between any of the network control servers, fixed base stations and subscriber terminals.

12. A system according to claim 11, wherein the network control messages relate to the transmission frequency at which base stations and subscriber terminals should transmit in each cell.