Method and system for contention resolution in telecommunication networks

• US 8,036,241 B2
• Filed: 03/09/2007
• Issued: 10/11/2011
• Est. Priority Date: 03/09/2007
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Semper, William Joseph, Ji, Baowei
• Primary Examiner(s): Vu; Huy
• Assistant Examiner(s): SEKUL, MARIA LYNN
• Application Number:
  US11/684,412
• Publication Number:
  US 20080219286A1
• Time in Patent Office: 1,677 Days
• Field of Search: 370/329, 370/437, 370/443
• US Class Current: 370/443
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]

Abstract

A method and system for contention resolution in a communications network are disclosed. As one example, a method for contention resolution in a communications network is disclosed. The method includes the steps of transmitting a first contention message during a first time interval, determining if a second contention message has been received during the first time interval, if the second contention message has been received during the first time interval, deferring a use of a network resource in the communications network, and if the second contention message has not been received during the first time interval, using the network resource during a second time interval.

Claims

1. A method for contention resolution in a communications network, the method comprising:

transmitting, by a base station, a first contention message for a network resource during a first time interval for use of the network resource in the next time interval;

counting, by the base station, a number of contention messages received during the same first time interval from other base stations contending for the next time interval;

if one or more contention messages are received during the first time interval, deferring, by the base station, a use of the network resource in the communications network during the next time interval; and

if one or more contention messages are not received during the first time interval, using, by the base station, the network resource during the next time interval,

wherein the transmitting and determining are performed concurrently or in parallel with a use of the network resource by the base station during the first time interval, and the transmitting is not performed over the network resource for which contention is being performed.

2. The method of claim 1, further comprising:

determining if the network resource is in use during the second time interval; and

if the network resource is in use during the second time interval, using the network resource during a third time interval, the third time interval subsequent in time to the next time interval.

3. The method of claim 1, wherein transmitting, determining and deferring are performed in an IP network concurrently or in parallel with a transmission of data over a radio air interface.

4. The method of claim 1, wherein the first contention message is a first “

claim”

message transmitted by a first base station, the second contention message is a second “

claim”

message transmitted by a second base station, and the steps of the method are performed for the first base station.

5. The method of claim 1, wherein the first contention message is a first signaling message, and the second contention message is a second signaling message.

6. The method of claim 1, wherein the first contention message comprises a messaging packet or frame, the first time interval comprises a first contention time slot, and the next time interval comprises a second contention time slot.

7. The method of claim 1, wherein deferring further comprises transmitting a third contention message during a third time interval.

8. The method of claim 1, wherein the network resource is a frequency channel.

9. The method of claim 1, wherein the communications network comprises at least one of a wireless network and a wire line network, and the first contention message and second contention message are conveyed on an Internet Protocol (IP) data communication link.

10. The method of claim 1, wherein the communications network comprises a Cognitive Radio-based communications network that includes a plurality of base stations, a plurality of signaling messages are conveyed between the base stations using an Internet Protocol format, and the network resource comprises a channel within a frequency spectrum associated with broadcast television.

11. A method for contention resolution by a first device in a communications network, the method comprising:

determining that a channel sharing contention condition exists;

generating a random number associated with a predefined duration of a contention window;

sending a first messaging packet or frame during a first contention time slot for using a network resource in the next contention time slot, the first messaging packet or frame associated with a predetermined probability value;

counting a number of messaging packets or frames received from one or more other devices during the first contention time slot;

if one or more messaging packets or frames are received from the one or more other devices, deferring use of a channel in contention during the next contention time slot; and

if one or more messaging packets or frames are not received from the second device, using the channel in contention during the next contention time slot,

wherein sending a first messaging packet or frame and determining if at least one messaging packet or frame was received from one or more other devices are performed concurrently or in parallel with a use of the channel in contention, and sending a first messaging packet or frame is not performed over the network resource for which contention is being performed.

12. The method of claim 11, further comprising:

determining by the second device if the first messaging packet or frame has been received from the first device substantially at the end of the contention time slot; and

if the first messaging packet or frame has been received, deferring use of the channel in contention by the second device.

13. The method of claim 11, wherein the method is performed in an IP network concurrently or in parallel with a transmission of data over a radio air interface.

14. The method of claim 11, wherein the first device comprises a first base station, the second device comprises a second base station, the communications network comprises a WRAN, and the first messaging packet or frame and the second messaging packet or frame are conveyed between devices using an Internet Protocol communication link.

15. The method of claim 11, wherein the random number comprises a random value, R, where R is associated with a range of values [0 CWin-1], and CWin is associated with a size of a contention window.

16. The method of claim 11, wherein deferring use of the channel in contention comprises waiting for the next contention time slot, and re-performing the method.

17. The method of claim 12, wherein the second device deferring use of the channel in contention comprises waiting for a release of the channel in contention, and re-performing the method.

18. A system for contention resolution in a communications network, the system comprising:

a first base station in the communications network;

a second base station in the communications network;

a second network; and

a plurality of communication links connected to the first base station, the second base station, and the second network, the plurality of communication links coupling the first base station to the second base station for communication, wherein the first base station is configured to;

transmit, by the first base station, a first contention message during a first time interval for using a network resource in the next time interval;

determine if a second contention message has been received during the first time interval by the second base station;

if the second contention message has been received during the first time interval, defer a use of a network resource in the communications network during the next time interval; and

if the second contention message has not been received during the first time interval, use the network resource during the next time interval,

wherein the first base station is configured to transmit the first contention message and determine if the second contention message has been received concurrently or in parallel with a use of the network resource by the first base station during the first time interval, and transmission of the first contention messages is not performed over the network resource for which contention is being performed.

19. The system of claim 18, wherein the first base station is further configured to:

determine if the network resource is in use during the next time interval; and

if the network resource is in use during the next time interval, use the network resource during a third time interval, the third time interval subsequent in time to the next time interval.