Methods and apparatus related to power control and/or interference management in a mixed wireless communications system supporting WAN signaling and peer to peer signaling

• US 8,452,317 B2
• Filed: 07/10/2007
• Issued: 05/28/2013
• Est. Priority Date: 09/15/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Junyi, Laroia, Rajiv
• Primary Examiner(s): Safaipour, Bobbak
• Application Number:
  US11/775,849
• Publication Number:
  US 20080069039A1
• Time in Patent Office: 2,149 Days
• Field of Search: 455/518, 455/519, 455/522, 370/318
• US Class Current: 455/522
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 52/08 Closed loop power control
• CPC Class Codes: H04W 52/10 Open loop power control
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/383 power control in peer-to-peer links
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

Methods and apparatus related to the sharing of wide area network (WAN) uplink bandwidth with peer to peer communication signaling usage are described. The base station regulates the level of interference from the peer to peer signaling by generating and transmitting peer to peer transmission power control signals intended for peer to peer wireless terminals in the local vicinity. A base station transmits into a downlink frequency band a signal, e.g., a beacon or broadcast channel signal, to be used by a peer to peer wireless terminal in controlling its peer to peer transmit power level into the corresponding uplink frequency band. The peer to peer wireless terminal receives and evaluates the base station signal. The determined information from the evaluation is used in determining whether or not peer to peer signal transmission is permitted and/or in determining a peer to peer transmission power level.

Claims

1. A method of operating a wireless communications device supporting peer to peer communications in a base station uplink frequency band, the method comprising:

receiving a first signal from a base station in a downlink frequency band;

performing an evaluation on the received signal to obtain information through both measuring a signal power of the first received signal and extracting encoded information conveyed in the first received signal wherein the transmission level of the first signal or the encoded information is varied by the base station to dynamically regulate interference to the base station uplink frequency band generated by a plurality of peer to peer wireless terminals; and

controlling peer to peer transmission power for at least some peer to peer signal transmissions in said uplink frequency band as a function of the result of the evaluation of said first received signal,

wherein controlling peer to peer transmission power includes using a first function that limits peer to peer transmission power to a lower level for a first received signal power level than for a second received signal power level which is higher than said first received signal power level.

2. The method of claim 1, further comprising:

receiving a second signal from said base station in said downlink frequency band at a time which is different from the time at which said first signal is received;

performing an evaluation on the second received signal; and

determining from the evaluation of the second received signal that said wireless communications device should refrain from transmitting peer to peer communications signals in said uplink frequency band.

3. The method of claim 2 further comprising:

refraining from transmitting peer to peer communications signals in said uplink frequency band after determining that the communications device should refrain from transmitting peer to peer communications signals until determining from evaluating another signal from said base station that said wireless communications device is permitted to transmit peer to peer signals.

4. The method of claim 1, wherein said first signal is a beacon signal.

5. The method of claim 4, wherein said beacon signal includes at most three OFDM tones, and wherein tones of the beacon signal have a per tone transmission power level that is at least 10 dBs higher than the average per tone transmission power level of a non-null tone of a peer to peer signal.

6. The method of claim 1, wherein said first signal is a broadcast channel signal.

7. The method of claim 6, wherein said broadcast channel signal includes a set of OFDM tones, and wherein tones of the broadcast channel signal have a per tone transmission power level that is at least 3 dBs higher than the average per tone transmission power level of a non-null tone of a peer to peer signal.

8. The method of claim 1, wherein said first signal is a CDMA pilot signal.

9. The method of claim 1 wherein said uplink and downlink frequency bands correspond to different non-overlapping frequency division duplex (FDD) WAN base station communications bands.

10. The method of claim 1, wherein said uplink frequency band corresponds to a base station time division duplex (TDD) band during uplink time slots and wherein said downlink frequency band corresponds to the same base station TDD band during downlink time slots.

11. The method of claim 1, wherein said first function determines a maximum permitted peer to peer transmission power level.

12. An apparatus comprising:

a processor for use in a wireless communications device supporting peer to peer communications in a base station uplink frequency band, the processor configured to;

receive a first signal from a base station in a downlink frequency band;

perform an evaluation on the received signal to obtain information through both measuring a signal power of the first received signal and extracting encoded information conveyed in the first received signal wherein the transmission level of the first signal or the encoded information is varied by the base station to dynamically regulate interference to the base station uplink frequency band generated by a plurality of peer to peer wireless terminals; and

control peer to peer transmission power for at least some peer to peer signal transmissions in said uplink frequency band as a function of the result of the evaluation of said first received signal,

wherein the peer to peer transmission power is controlled using a first function that limits peer to peer transmission power to a lower level for a first received signal power level than for a second received signal power level which is higher than said first received signal power level.

13. The apparatus of claim 12, wherein said processor is further configured to:

receive a second signal from said base station in said downlink frequency band at a time which is different from the time at which said first signal is received;

perform an evaluation on the second received signal; and

determine from the evaluation of the second received signal that said wireless communications device should refrain from transmitting peer to peer communications signals in said uplink frequency band.

14. The apparatus of claim 13, wherein said processor is further configured to:

control the communications device to refrain from transmitting peer to peer communications signals in said uplink frequency band after determining that the communications device should refrain from transmitting peer to peer communications signals until determining from evaluating another signal from said base station that said wireless communications device is permitted to transmit peer to peer signals.

15. A non-transitory machine readable medium embodying machine executable instructions for controlling a wireless communications device supporting peer to peer communications in a base station uplink frequency band to implement a method of communicating with another communications device, the method comprising:

receiving a first signal from a base station in a downlink frequency band;

performing an evaluation on the received signal to obtain information through both measuring a signal power of the first received signal and extracting encoded information conveyed in the first received signal wherein the transmission level of the first signal or the encoded information is varied by the base station to dynamically regulate interference to the base station uplink frequency band generated by a plurality of peer to peer wireless terminals; and

controlling peer to peer transmission power for at least some peer to peer signal transmissions in said uplink frequency band as a function of the result of the evaluation of said first received signal,

wherein controlling peer to peer transmission power includes using a first function that limits peer to peer transmission power to a lower level for a first received signal power level than for a second received signal power level which is higher than said first received signal power level.

16. The non-transitory machine readable medium of claim 15, further embodying machine executable instructions for:

receiving a second signal from said base station in said downlink frequency band at a time which is different from the time at which said first signal is received;

performing an evaluation on the second received signal; and

determining from the evaluation of the second received signal that said wireless communications device should refrain from transmitting peer to peer communications signals in said uplink frequency band.

17. The non-transitory machine readable medium of claim 16, further embodying machine executable instructions for:

refraining from transmitting peer to peer communications signals in said uplink frequency band after determining that the communications device should refrain from transmitting peer to peer communications signals until determining from evaluating another signal from said base station that said wireless communications device is permitted to transmit peer to peer signals.

18. A wireless communications device supporting peer to peer communications in a base station uplink frequency band, the wireless communications device comprising:

a receiver module for receiving a first signal from a base station in a downlink frequency band;

a signal processing module for performing an evaluation on the received signal to obtain information, the signal processing module comprising a power measurement module for measuring a signal power of the first received signal and a decoder module for extracting encoded information conveyed in the first received signal, the obtained information comprising both the signal power measurement and the extracted encoded information signal wherein the transmission level of the first signal or the encoded information is varied by the base station to dynamically regulate interference to the base station uplink frequency band generated by a plurality of peer to peer wireless terminals; and

a peer to peer transmission power control module for controlling peer to peer transmission power for at least some peer to peer signal transmissions in said uplink frequency band as a function of the result of the evaluation of said first received signal,

wherein said peer to peer transmission power control module controls peer to peer transmission power using a first function that limits peer to peer transmission power to a lower level for a first received signal power level than for a second received signal power level which is higher than said first received signal power level.

19. The wireless communications device of claim 18, further comprising:

a peer to peer authorization module for determining from the evaluation of the received signal whether the wireless communications device is permitted to transmit peer to peer communications signals in said uplink frequency band or whether the wireless terminal is restricted from transmitting peer to peer communications signals in said uplink frequency band.

20. The wireless communications device of claim 18, wherein said first signal is a beacon signal.

21. The wireless communications device of claim 20, wherein said beacon signal includes at most three OFDM tones, and wherein tones of the beacon signal have a per tone transmission power level that is at least 10 dBs higher than the average per tone transmission power level of a non-null tone of a peer to peer signal, the apparatus further comprising:

a memory including stored information characterizing a base station sourced beacon signal which is used for peer to peer transmission power control; and

a peer to peer transmission power control beacon identification module for identifying said beacon signal.

22. The wireless communications device of claim 18, wherein said first signal is a broadcast channel signal.

23. The wireless communications device of claim 22, wherein said broadcast channel signal includes a set of OFDM tones, and wherein tones of the broadcast channel signal have a per tone transmission power level that is at least 3 dBs higher than the average per tone transmission power level of a non-null tone of a peer to peer signal, the wireless communications device further comprising:

a memory including stored information characterizing a base station sourced broadcast channel signal used for peer to peer transmission power control; and

a peer to peer transmission power control broadcast identification module for identifying said broadcast channel signal.

24. The wireless communications device of claim 18, wherein said first signal is a CDMA pilot signal.

25. The wireless communications device of claim 18 wherein said uplink and downlink frequency bands correspond to different non-overlapping frequency division duplex (FDD) WAN base station communications bands, the wireless communications device further comprising:

a memory including stored FDD air link resource structure information.

26. The wireless communications device of claim 18, wherein said uplink frequency band corresponds to a base station time division duplex (TDD) band during uplink time slots and wherein said downlink frequency band corresponds to the same base station TDD band during downlink time slots, the wireless communications device further comprising:

a memory included stored TDD air link resource structure information.

27. The wireless communications device of claim 18, wherein said first function determines a maximum permitted peer to peer transmission power level.

28. A wireless communications device supporting peer to peer communications in a base station uplink frequency band, the wireless communications device comprising:

receiver means for receiving a first signal from a base station in a downlink frequency band;

means for performing an evaluation on the received signal to obtain information, the means for performing the evaluation comprising means for measuring a power level of the first received signal and means for extracting encoded information conveyed in the first received signal, the obtained information comprising the measured power level and the extracted encoded information signal wherein the transmission level of the first signal or the encoded information is varied by the base station to dynamically regulate interference to the base station uplink frequency band generated by a plurality of peer to peer wireless terminals; and

means for controlling peer to peer transmission power for at least some peer to peer signal transmissions in said uplink frequency band as a function of the result of the evaluation of said first received signal,

wherein said means for controlling controls peer to peer transmission power using a first function which limits peer to peer transmission power to a lower level for a first received signal power level than for a second received signal power level which is hi her than said first received signal power level.

29. The wireless communications device of claim 28, further comprising:

means for determining from the evaluation of the received signal whether the wireless communications device is permitted to transmit peer to peer communications signals in said uplink frequency band or whether the wireless terminal is restricted from transmitting peer to peer communications signals in said uplink frequency band.