SUPPORTING A LARGE NUMBER OF DEVICES IN WIRELESS COMMUNICATIONS

• US 20130235720A1
• Filed: 03/05/2013
• Published: 09/12/2013
• Est. Priority Date: 03/06/2012
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Wang, Xiaofei, Wang, Lei, Zhang, Guodong, Grandhi, Sudheer A.
• Granted Patent: US 9,854,469 B2
• Time in Patent Office: Days
• US Class Current: 370/229
• CPC Class Codes: H04W 28/0278 using buffer status reports dynamic wireless traffic scheduling definition H04W72/12
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for receiving a backoff value at a wireless station is presented. A traffic indication map is received at the station, wherein a backoff number is implicitly assigned to the station based on a position of the station within the traffic indication map. The backoff value is determined by multiplying the backoff number by a predetermined time value.

Claims

1. A method for determining a backoff value at a wireless station, comprising:

receiving a traffic indication map at the station, wherein a backoff number is implicitly assigned to the station based on a position of the station within the traffic indication map; and

determining the backoff value by multiplying the backoff number by a predetermined time value.

2. The method according to claim 1, wherein the predetermined time value is a fixed value.

3. The method according to claim 1, wherein the predetermined time value is received at the station via any one of:

a beacon, a probe response frame, an association response frame, a management frame, or a control frame.

4. The method according to claim 1, further comprising:

setting a backoff timer at the station with the determined backoff value; and

attempting to send a communication by the station after the backoff timer has expired.

5. A wireless station, comprising:

a transceiver configured to receive a traffic indication map, wherein a backoff number is implicitly assigned to the station based on a position of the station within the traffic indication map; and

a processor in communication with the transceiver, the processor configured to determine a backoff value for the station by multiplying the backoff number by a predetermined time value.

6. The wireless station according to claim 5, wherein the predetermined time value is a fixed value.

7. The wireless station according to claim 5, wherein the transceiver is configured to receive the predetermined time value via any one of:

a beacon, a short beacon, a probe response frame, an association response frame, a Fast Initial Link Setup discovery frame, a management frame, or a control frame.

8. The wireless station according to claim 5, further comprising:

a backoff timer in communication with the processor, the backoff timer being set to the determined backoff value, wherein the transceiver attempts to send a communication after the backoff timer has expired.

9. A method for assigning a backoff value to a wireless station, comprising:

sending a traffic indication map to the station, wherein a backoff number is implicitly assigned to the station based on a position of the station within the traffic indication map; and

determining the backoff value by multiplying the backoff number by a predetermined time value.

10. The method according to claim 9, wherein the predetermined time value is a fixed value.

11. The method according to claim 9, wherein the predetermined time value is sent to the station via any one of:

a beacon, a short beacon, a probe response frame, an association response frame, a Fast Initial Link Setup discovery frame, a management frame, or a control frame.

12. The method according to claim 9, further comprising:

receiving a communication from the station after the determined backoff value has elapsed.

13. A method for receiving a backoff value at a wireless station, comprising:

receiving a traffic indication map at the station; and

on a condition that the traffic indication map (TIM) contains a positive traffic indication for the station, using a hash function with a predetermined set of parameters to determine the backoff value for the station.

14. The method according to claim 13, wherein the predetermined set of parameters includes an association identifier of the station and a bitmap position of the station within the TIM or an i^th positive indication in the TIM.

15. The method according to claim 14, wherein the predetermined set of parameters further includes any one or more of:

a basic service set identifier of a basic service set that transmitted the traffic indication map;

a medium access control address of an access point that transmitted the traffic indication map;

a timing synchronization function value of an access point with which the station is associated;

a neighbor access point timing synchronization function offset, with respect to the timing synchronization function of the access point with which the station is associated;

a slot time;

or

a total number of positive traffic indication map indications of a basic service set or an overlapping basic service set.

16. The method according to claim 13, further comprising:

setting a backoff timer at the station with the determined backoff value; and

attempting to send a communication by the station after the backoff timer has expired.

17. A wireless station, comprising:

a transceiver configured to receive a traffic indication map (TIM); and

a processor in communication with the transceiver, the processor configured to use a hash function with a predetermined set of parameters to determine a backoff value for the station on a condition that the TIM contains a positive traffic indication for the station.

18. The wireless station according to claim 17, wherein the predetermined set of parameters includes an association identifier of the station and a bitmap position of the station within the TIM.

19. The wireless station according to claim 18, wherein the predetermined set of parameters further includes any one or more of:

a basic service set identifier of a basic service set that transmitted the traffic indication map;

a medium access control address of an access point that transmitted the traffic indication map;

a timing synchronization function value of an access point with which the station is associated;

a neighbor access point timing synchronization function offset, with respect to the timing synchronization function of the access point with which the station is associated;

a slot time;

or

a total number of positive traffic indication map indications of a basic service set or an overlapping basic service set.

20. The wireless station according to claim 17, further comprising:

a backoff timer in communication with the processor, the backoff timer being set to the determined backoff value, wherein the transceiver attempts to send a communication after the backoff timer has expired.

21. A method for assigning a backoff value to a wireless station, comprising:

sending a traffic indication map (TIM) to the station; and

on a condition that the TIM contains a positive traffic indication for the station, using a hash function with a predetermined set of parameters to determine the backoff value for the station.

22. The method according to claim 21, wherein the predetermined set of parameters includes an association identifier of the station and a bitmap position of the station within the TIM or an i^th positive indication in the TIM.

23. The method according to claim 22, wherein the predetermined set of parameters further includes any one or more of:

a basic service set identifier of a basic service set that transmitted the traffic indication map;

a medium access control address of an access point that transmitted the traffic indication map;

a timing synchronization function value of an access point with which the station is associated;

a neighbor access point timing synchronization function offset, with respect to the timing synchronization function of the access point with which the station is associated;

a slot time;

or

a total number of positive traffic indication map indications of a basic service set or an overlapping basic service set.

24. The method according to claim 21, further comprising:

receiving a communication from the station after the determined backoff value has elapsed.