Fairness in clear channel assessment under long sensing time

Patent metadata

Field	Value
Publication number	US-10034304-B2
Application number	US-201514869372-A
Country	US
Kind code	B2
Filing date	Sep 29, 2015
Priority date	Jun 26, 2015
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

Mechanisms for clear channel assessment associated with a communication channel in a wireless environment are provided. Implementation of the mechanisms provides fairness in the utilization of wireless communication resources among contemporaneous communication devices and legacy communication devices. The communication channel can be embodied in a primary channel or a secondary channel according to communication protocols within the IEEE 802.11 family of protocols.

First claim

What is claimed is:

1. At least one computer-readable non-transitory storage medium having instructions stored thereon that, when executed by one or more processors of a communication device, direct the one or more processors to perform operations comprising:
determining a sensing interval associated with performing a clear channel assessment in a communication channel;
determining an interframe spacing representing a time interval during which to perform the clear channel assessment;
detecting that a signal is present in the communication channel during a backoff period, wherein the backoff period follows the interframe spacing and comprises one or more backoff slots;
determining a number of the one or more backoff slots which overlap the sensing interval; and
increasing the backoff period by the number of the one or more backoff slots which overlap the sensing interval.

2. The at least one computer-readable non-transitory storage medium of claim 1 , wherein the operations further comprise restarting a backoff operation using the increased backoff period.

3. The at least one computer-readable non-transitory storage medium of claim 1 , wherein the signal comprises a transmission frame according to a defined communication protocol, and wherein the operations further comprise:
determining that a power of the transmission frame is greater than a defined threshold value; and
deferring contention for the communication channel for a defined deferral period spanned by consecutive fields in the transmission frame.

4. The at least one computer-readable non-transitory storage medium of claim 1 , wherein the signal comprises a transmission frame according to a defined communication protocol, and wherein the operations further comprise:
determining that a power of the transmission frame is greater than a defined threshold value;
configuring a power threshold associated with a second clear channel assessment to be equal to the defined threshold value for detection of a second signal according to the defined communication protocol;
monitoring presence of the second signal in the communication channel using the second clear channel assessment;
monitoring presence of the second signal in the communication channel using the clear channel assessment; and
configuring the power threshold to be equal to a second defined threshold value in response to the detecting via the clear channel assessment.

5. The at least one computer-readable non-transitory storage medium of claim 4 , wherein the monitoring the presence of the second signal using the clear channel assessment comprises correlating symbols associated with the second signal, and wherein the monitoring the presence of the second signal using the second clear channel assessment comprises evaluating an amount of energy associated with a portion of the second signal.

6. The at least one computer-readable non-transitory storage medium of claim 1 , wherein the operations further comprise determining that the interframe spacing and a defined second number of the one or more backoff slots associated with the backoff period span an interval less than the sensing interval.

7. The at least one computer-readable non-transitory storage medium of claim 6 , wherein the operations further comprise reducing the sensing interval to match the interval.

8. The at least one computer-readable non-transitory storage medium of claim 6 , wherein the operations comprise foregoing implementation of the clear channel assessment.

9. The at least one computer-readable non-transitory storage medium of claim 6 , wherein the operations further comprise adding a defined third number of the one or more backoff slots to the defined second number of the one or more backoff slots, and wherein the defined third number of the one or more backoff slots and the defined second number of the one or more backoff slots span a second interval at least equal to the sensing interval.

10. The at least one computer-readable non-transitory storage medium of claim 6 , wherein the operations further comprise selecting a defined third number of the one or more backoff slots greater than the defined second number of the one or more backoff slots, and wherein the defined third number of the one or more backoff slots and the interframe spacing span a second interval at least equal to the sensing interval.

11. The at least one computer-readable non-transitory storage medium of claim 10 , wherein the selecting the defined third number of the one or more backoff slots comprises randomly drawing the defined third number of the one or more backoff slots.

12. At least one computer-readable non-transitory storage medium having instructions stored thereon that, when executed by one or more processors of a communication device, direct the one or more processors to perform operations comprising:
configuring a sensing interval for a clear channel assessment in a communication channel;
determining an interframe spacing representing a time interval during which to perform the clear channel assessment;
performing the clear channel assessment using the sensing interval, wherein the performing comprises correlating symbols having respective defined data symbol durations, wherein a defined data symbol duration of the respective defined data symbol durations is one of 12.8 μs or 3.2 μs;
detecting that a signal is present in the communication channel during a backoff period, wherein the backoff period follows the interframe spacing and comprises one or more backoff slots;
determining a number of the one or more backoff slots which overlap the sensing interval; and
increasing the backoff period by the number of the one or more backoff slots which overlap the sensing interval.

13. The at least one computer-readable non-transitory storage medium of claim 12 , wherein the communication channel comprises a primary channel according to an IEEE 802.11 communication protocol, and wherein the correlating comprises correlating symbols each having a data symbol duration of about 12.8 μs.

14. The at least one computer-readable non-transitory storage medium of claim 12 , wherein the communication channel comprises a secondary channel according to an IEEE 802.11 communication protocol, and wherein the correlating comprises correlating first symbols each having a first data symbol duration of about 3.2 μs and further correlating second symbols each having a second data symbol duration of about 12.8 μs.

15. A communication device, comprising:
at least one memory device that stores computer-executable instructions; and
one or more processors coupled to the at least one memory device, at least one processor of the one or more processors being configured to access the at least one memory device, and being further configured to execute the computer-executable instructions to:
determine a sensing interval associated with performing a clear channel assessment in a communication channel;
determine an interframe spacing representing a time interval during which to perform the clear channel assessment;
detect that a signal is present in the communication channel during a backoff period, wherein the backoff period follows the interframe spacing and comprises one or more backoff slots;
determine a number of the one or more backoff slots which overlap the sensing interval; and
increase the backoff period by the number of the one or more backoff slots which overlap the sensing interval.

16. The communication device of claim 15 , wherein the at least one processor of the one or more processors is further configured to execute the computer-exe

Assignees

• Huang Po Kai
• Li Qinghua
• Cariou Laurent
• Chen Xiaogang
• Intel Ip Corp

Inventors

• Huang Po-Kai
• Li Qinghua
• Cariou Laurent
• Chen Xiaogang

Classifications

• H04W52/0216

  using a pre-established activity schedule, e.g. traffic indication frame · CPC title

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04W52/0229

  where the received signal is a wanted signal · CPC title

• H04W74/0808 Primary

  using carrier sensing, e.g. carrier sense multiple access [CSMA] · CPC title

• Y02D70/26

  Cross-Sectional Technologies · mapped topic