System and method for variably delaying access requests in wireless communications system

• US 6,535,736 B1
• Filed: 12/11/1998
• Issued: 03/18/2003
• Est. Priority Date: 12/11/1998
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Huang, Ching Yao, Cheng, Terry Si-Fong, Burgess, John K., Balogh, Dan Anthony, Yu, Shawn S.
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): Gesesse, Tilahun
• Application Number:
  US09/210,019
• Time in Patent Office: 1,558 Days
• Field of Search: 455/434, 455/423, 455/424, 455/450, 455/452, 455/458, 455/464, 455/515, 455/516, 455/453
• US Class Current: 455/434
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
• CPC Class Codes: H04W 74/00 Wireless channel access

Abstract

The present invention, in illustrative embodiments, implements systems and methods for adjusting the timing of access requests in mobile communications systems, such as IS-95-A mobile telephone systems, to reduce the likelihood of request collisions—especially during periods of very high calling rates. These embodiments employ measurements of access channel occupancy, as well as system operator inputs, to develop thresholds and parameter translations at a base station. Execution of control algorithms at a base station advantageously yields modified persistence test parameters sent to mobile stations. When overload conditions are present, these modified parameters cause the mobile stations to experience variable delays through judicious control of persistence testing at the mobile stations.

Claims

1. A method for variably delaying access requests over at least one access channel from each of a plurality of terminals to a shared resource, origination of access requests at said terminals being subject to a pseudo-random delay characterized by a first parameter, the method comprising

generating one or more occupancy signals reflecting the relative occupancy of said access channels,

based on said occupancy signals, generating an adjustment signal representing a modification of said first parameter, and

making said adjustment signal available to at least some of said terminals,

wherein each of said channels is arranged to receive messages in sequential access slots, each of said slots comprising a plurality of frames, each of said messages comprising a message preamble and a message capsule, and said generating of said one or more occupancy signals reflecting the relative occupancy of said access channels comprises determining for each access channel the % interval occupancy in accordance with

2. The method of claim 1, wherein said adjustment signal represents an incremented value for said first parameter.

3. The method of claim 1, wherein said adjustment signal represents a decremented value for said first parameter.

4. The method of claim 1, wherein said generating of said adjustment signal comprises

receiving a first threshold signal, T_H,

comparing said T_H with said occupancy signal, and

generating said adjustment signal in accordance with at least one pre-defined relationship between said occupancy signal and said T_H.

5. The method of claim 4, wherein said generating said adjustment signal in accordance with at least one pre-defined relationship comprises

generating an adjustment signal to change said first parameter signal to a value tending to increase the delay of said originations.

6. The method of claim 5 wherein said adjustment signal causes said first parameter to be incremented.

7. The method of claim 5 wherein said adjustment signal causes said first parameter to be replaced by a value corresponding to a longer average delay.

8. The method of claim 4 wherein said generating said adjustment signal in accordance with at least one pre-defined relationship comprises

generating an adjustment signal to change said first parameter signal to a value tending to decrease the delay of said originations.

9. The method of claim 8 wherein said adjustment signal causes said first parameter to be incremented.

10. The method of claim 8 wherein said adjustment signal causes said first parameter to be replaced by a value corresponding to a longer average delay.

11. The method of claim 1, wherein said channels are mobile communications access channels.

12. A system for variably delaying access requests over at least one access channel from each of a plurality of terminals to a shared resource, origination of access requests at said terminals being subject to a pseudo-random delay characterized by a first parameter, the method comprising

means for generating one or more occupancy signals reflecting the relative occupancy of said access channels, and

means for generating an adjustment signal based on said occupancy signals, said adjustment signal representing a modification of said first parameter, and

making said adjustment signal available to at least some of said terminals,

wherein each of said channels is arranged to receive messages in sequential access slots, each of said slots comprising a plurality of frames, each of said messages comprising a message preamble and a message capsule, and said means for generating said one or more occupancy signals reflecting the relative occupancy of said access channels comprises means for determining for each access channel the percent interval occupancy in accordance with

13. The system of claim 12, wherein said adjustment signal represents an incremented value for said first parameter.

14. The system of claim 12, wherein said adjustment signal represents a decremented value for said first parameter.

15. The system of claim 12, wherein said means for generating said adjustment signal comprises

means for receiving a first threshold signal, T_H,

means for comparing said T_H with said occupancy signal, and

means for generating said adjustment signal in accordance with at least one pre-defined relationship between said occupancy signal and said T_H.

16. The system of claim 15, wherein said means for generating said adjustment signal in accordance with at least one pre-defined relationship comprises

means for generating an adjustment signal to change said first parameter signal to a value tending to increase the delay of said originations.

17. The system of claim 15 wherein said adjustment signal causes said first parameter to be incremented.

18. The system of claim 15 wherein said adjustment signal causes said first parameter to be replaced by a value corresponding to a longer average delay.

19. The system of claim 15 wherein said means for generating said adjustment signal in accordance with at least one pre-defined relationship comprises

means for generating an adjustment signal to change said first parameter signal to a value tending to decrease the delay of said access requests.

20. The system of claim 19 wherein said means for generating said adjustment signal causes said first parameter to be incremented.

21. The system of claim 19 wherein said means for generating said adjustment signal causes said first parameter to be replaced by a value corresponding to a longer average delay.

22. The system of claim 12, wherein said access channels are mobile communications channels, and wherein said means for making said adjustment signal available to at least some of said terminals comprises a paging channel.