TRANSMIT OPPORTUNITY (TXOP) BASED CHANNEL REUSE

• US 20140328270A1
• Filed: 05/02/2014
• Published: 11/06/2014
• Est. Priority Date: 05/03/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zhu, Hao, Katar, Srinivas, Merlin, Simone, Zou, Chao, Barriac, Gwendolyn Denise, Cherian, George, Abraham, Santosh Paul, Yonge, Lawrence Winston III, Sampath, Hemanth
• Granted Patent: US 9,622,262 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02

Abstract

A method includes determining, at a first transmitter, a clear channel access (CCA) threshold associated with reuse of a first transmit opportunity (TXOP) of a message. The method further includes sending, from the first transmitter to a first receiver, at least a portion of the message, wherein the portion of the message indicates the CCA threshold.

Claims

1. A method comprising:

determining, at a first transmitter, a clear channel access (CCA) threshold associated with reuse of a first transmit opportunity (TXOP) of a message; and

sending, from the first transmitter to a first receiver, at least a portion of the message, wherein the portion of the message indicates the CCA threshold.

2. The method of claim 1, wherein the CCA threshold is dynamically determined by the first transmitter prior to sending the message.

3. The method of claim 1, wherein the CCA threshold is determined based on a signal strength of a link between the first transmitter and the first receiver in a basic service set (BSS), based on an interference level of an overlapping basic service set (OBSS), based on a previous CCA threshold used in association with a particular message communicated by the first transmitter prior to the message, or a combination thereof.

4. The method of claim 1, wherein the portion of the message indicates the CCA threshold based on a value in a signal (SIG) field.

5. The method of claim 1, wherein the CCA threshold is determined prior to sending the message.

6. The method of claim 1, wherein the CCA threshold indicated by the portion of the message is less than a standard-based CCA threshold associated with reuse of the first TXOP.

7. The method of claim 6, wherein the standard-based CCA threshold is −

62 dBm, where dBm is a power ratio in decibels (dB) of a measured power referenced to one milliwatt (mW).

8. A method comprising:

detecting, at a reuse transmitter, a portion of a message sent by a first transmitter, wherein the message is associated with a first transmit opportunity (TXOP); and

determining, based on the portion, a clear channel access (CCA) threshold associated with reuse of the first TXOP.

9. The method of claim 8, wherein the CCA threshold corresponds to an amount of interference tolerable by the first transmitter.

10. The method of claim 8, further comprising, when reuse of the first TXOP is permitted, determining at the reuse transmitter whether to reuse the first TXOP.

11. The method of claim 10, wherein a determination to reuse the first TXOP is based on whether a CCA level of the first transmitter is less than or equal to the CCA threshold.

12. The method of claim 8, wherein a determination to reuse the first TXOP is based on a power level of the first transmitter, whether the message is addressed to the reuse transmitter, whether a second message to be sent by the reuse transmitter during reuse of the first TXOP is addressed to a first receiver of the message, whether a network allocation vector (NAV) that is honored by the reuse transmitter was set by the first transmitter, or a combination thereof.

13. The method of claim 8, wherein a determination to reuse the first TXOP is based on a physical proximity of the reuse transmitter to a reuse receiver.

14. The method of claim 8, wherein a determination to reuse the first TXOP is based on a handshake exchange between the reuse transmitter and a reuse receiver.

15. The method of claim 8, further comprising:

in response to determining to reuse the first TXOP, sending a second message from the reuse transmitter during the first TXOP, wherein the second message is sent based on the CCA threshold; and

determining whether to reuse a second TXOP that is subsequent to the first TXOP, wherein a determination to reuse the second TXOP is based on whether the first message is received by the first receiver, whether the second message is received by the reuse receiver, historical data, or a combination thereof.

16. A method comprising:

determining, at a reuse transmitter, that reuse of a first transmit opportunity (TXOP) associated with a first message is permitted, wherein the first message is sent from a first transmitter to a first receiver; and

determining whether to reuse the first TXOP based on a receiver (RX) clear channel access (CCA) threshold associated with the first receiver.

17. The method of claim 16, wherein the RX CCA threshold corresponds to an amount of interference tolerable by the first receiver.

18. The method of claim 16, further comprising determining, at the reuse transmitter, the RX CCA threshold.

19. The method of claim 18, wherein the reuse transmitter determines the RX CCA threshold based on one or more bits included in a signal (SIG) field associated with the first message.

20. The method of claim 18, wherein the reuse transmitter determines the RX CCA threshold based on a block acknowledgement (BA) sent by the first receiver, and wherein the BA is responsive to a particular message sent prior to the first message.

21. The method of claim 18, wherein the reuse transmitter determines the RX CCA threshold based on a management message received from the first receiver.

22. The method of claim 18, wherein the reuse transmitter determines the RX CCA threshold based on a request to send (RTS) message or a clear to send (CTS) message sent from the first receiver, and wherein the RTS message or the CTS message is associated with a particular message sent prior to the first message.

23. A method comprising:

detecting, at a reuse transmitter, a portion of a message sent by a first receiver; and

determining, based on the portion, a receiver (RX) clear channel access (CCA) threshold associated with reuse of a first TXOP.

24. The method of claim 23, wherein the portion is included in a clear to send (CTS) message, and wherein the CTS message is sent by the first receiver to a first transmitter responsive to a request to send (RTS) message sent by the first transmitter to the first receiver.

25. The method of claim 23, further comprising, when reuse of the first TXOP is permitted, determining at the reuse transmitter whether to reuse the first TXOP.

26. The method of claim 25, wherein a determination to reuse the first TXOP is based on whether a first CCA level of the portion is less than or equal to the RX CCA threshold.

27. The method of claim 26, wherein a determination to reuse the first TXOP is based on whether a second CCA level of a first transmitter is less than or equal to a CCA threshold associated with the first TXOP, whether the message is addressed to the reuse transmitter, whether a second message to be sent by the reuse transmitter during reuse of the first TXOP is addressed to the first receiver to receive the message during the first TXOP, whether a network allocation vector (NAV) that is honored by the reuse transmitter was set by the first TX, or a combination thereof.

28. The method of claim 25, wherein a determination to reuse the first TXOP is based on a physical proximity of the reuse transmitter to a reuse receiver.

29. The method of claim 25, further comprising:

reusing the first TXOP to send a second message during the first TXOP, wherein the second message is sent based on a CCA threshold;

performing a performance assessment associated with communication of the second message; and

based on the performance assessment, determining whether to reuse a second TXOP subsequent to the first TXOP.

30. The method of claim 23, further comprising:

identifying a modulation and coding scheme (MCS) associated with the message; and

adjusting the RX CCA threshold based on the MCS.