Supporting a large number of devices in wireless communications

• US 9,854,469 B2
• Filed: 03/05/2013
• Issued: 12/26/2017
• 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.
• Primary Examiner(s): Rinehart, Mark
• Assistant Examiner(s): Dewan, Sanjay K
• Application Number:
  US13/785,842
• Publication Number:
  US 20130235720A1
• Time in Patent Office: 1,757 Days
• Field of Search: 370229, 370252, 370328, 370312, 340 11, 340 71, 340 72, 340 732, 340 733, 340 734, 340 735, 340 736, 340 737, 340 738
• 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 to provide access to a medium, the method comprising:

receiving a time value at a wireless station;

receiving a traffic indication map (TIM) element at the wireless station, wherein the TIM element comprises bits mapped to an association identifier (AID) of the wireless station;

on a condition that an indication for accessing a channel in a time interval for wireless stations having AIDs associated with a positive indication in the TIM element is received at the wireless station, determining a backoff number for the wireless station as a function of an index of the AID of the wireless station;

on a condition that the indication is not received at the wireless station, determining the backoff number for the wireless station as a function of the AID of the wireless station; and

determining a medium access backoff time for the wireless station by multiplying the backoff number by the time value.

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

3. The method according to claim 1, wherein the time value is received at the wireless station via a beacon or a short beacon.

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

setting a backoff timer at the wireless station with the medium access backoff time; and

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

5. The method according to claim 1, wherein the medium access backoff time is a slot time.

6. The method according to claim 1, further comprising signaling the medium access backoff time using at least one of a beacon or a short beacon.

7. The method according to claim 1, wherein the index is associated with the positive indication in the TIM element.

8. A wireless station, comprising:

a transceiver configured to receive a time value and a traffic indication map (TIM) element, wherein the TIM element comprises bits mapped to an association identifier (AID) of the wireless station; and

a processor in communication with the transceiver, the processor configured to

on a condition that an indication for accessing a channel in a time interval for wireless stations having AIDs associated with a positive indication in the TIM element is received at the wireless station, determine a backoff number for the wireless station as a function of an index of the AID of the wireless station;

on a condition that the indication is not received at the wireless station, determine the backoff number for the wireless station as a function of the AID of the wireless station; and

determine a medium access backoff time for the wireless station by multiplying the backoff number by the time value.

9. The wireless station according to claim 8, wherein the time value is a fixed value.

10. The wireless station according to claim 8, wherein the transceiver is configured to receive the time value via a beacon or a short beacon.

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

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

12. The wireless station according to claim 8, wherein the medium access backoff time is a slot time.

13. The wireless station according to claim 8, wherein the transceiver is configured to signal the medium access backoff time using at least one of a beacon or a short beacon.

14. The wireless station according to claim 8, wherein the index is associated with the positive indication in the TIM element.