METHOD AND SYSTEM FOR CONTENTION RESOLUTION IN TELECOMMUNICATION NETWORKS

• US 20080219286A1
• Filed: 03/09/2007
• Published: 09/11/2008
• Est. Priority Date: 03/09/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Semper, William Joseph, Ji, Baowei
• Granted Patent: US 8,036,241 B2
• Time in Patent Office: Days
• US Class Current: 370/445
• 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, comprising 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.

2. The method of claim 1, further comprising the steps of:

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 second time interval.

3. The method of claim 1, wherein the transmitting, determining and deferring steps are performed concurrently or in parallel with a use of the network resource.

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

5. 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.

6. 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.

7. 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 second time interval comprises a second contention time slot.

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

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

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

11. 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.

12. A method for contention resolution in a communications network, comprising the steps of:

a first device determining that a channel sharing contention condition exists;

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

the first device sending a first messaging packet or frame substantially at the beginning of a contention time slot, the first messaging packet or frame associated with a predetermined probability value;

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

if the first device determines that the at least a second messaging packet or frame has been received from the second device, the first device deferring use of a channel in contention; and

if the first device determines that the at least a second messaging packet or frame has not been received from the second device, the first device using the channel in contention.

13. The method of claim 12, further comprising the steps of:

the second device determining 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 second device determines that the first messaging packet or frame has been received, the second device deferring use of the channel in contention.

14. The method of claim 12, wherein the steps are performed concurrently or in parallel with a use of the network resource.

15. The method of claim 12, wherein the steps are performed in an IP network concurrently or in parallel with a transmission of data over a radio air interface.

16. The method of claim 12, 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.

17. The method of claim 12, 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.

18. The method of claim 12, wherein the step of deferring use of the channel in contention comprises waiting for the next contention time slot, and re-performing the steps of the method.

19. The method of claim 13, wherein the step of the second device deferring use of the channel in contention comprises waiting for a release of the channel in contention, and re-performing the steps of the method.

20. A method for coordinating an assignment of frequency channels in a communications network, comprising the steps of:

a first base station sending a channel use request message to a second base station, the channel use request message including a request by the first base station to share a channel in use by the second base station; and

in response to receiving the channel use request message, the second base station sending a channel use response message to the first base station, the channel use response message including an identity of at least one channel and at least one time slot to be shared with the first base station.

21. The method of claim 20, wherein the channel use request message and the channel use response message are structured in accordance with Internet Protocol message formats.

22. A method for coordinating an assignment of frequency channels in a communications network, comprising the steps of:

a first base station sending a channel use update message to a second base station, the channel use update message including an identity of at least one time slot or channel that has been released from use by the first base station; and

in response to receiving the channel use update message, the second base station sending a channel use update acknowledgment message indicating that the second base station received the channel use update message.

23. A method for coordinating an assignment of frequency channels in a communications network, comprising the steps of:

a first base station sending a spectrum use notification message to a second base station, the spectrum use notification message including a request by the first base station for the second base station to reserve at least one channel for use by the first base station; and

in response to receiving the spectrum use notification message, the second base station sending a spectrum use notification acknowledgment message to the first base station, the spectrum use notification acknowledgment message including an identity of one or more channels reserved for use by the first base station.

24. A method for coordinating an assignment of frequency channels in a communications network, comprising the steps of:

a second base station sending a spectrum use notification message to a first base station, the spectrum use notification message including a request by the second base station for the first base station to revoke a reservation of at least one channel from use by the first base station; and

in response to receiving the spectrum use notification message, the first base station sending a spectrum use notification acknowledgment message to the second base station, the spectrum use notification acknowledgment message including an identity of one or more channels that are released from a reservation for use by the first base station.

25. The method of claim 24, wherein the at least one channel is identified on a list of candidate channels.

26. A system for contention resolution in a communications network, 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 a first contention message during a first time interval;

determine 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, defer 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, use the network resource during a second time interval.

27. The system of claim 26, wherein the first base station is further configured to:

determine 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, use the network resource during a third time interval, the third time interval subsequent in time to the second time interval.