UPLINK POWER CONTROL FOR WIRELESS COMMUNICATION

• US 20110105059A1
• Filed: 04/21/2010
• Published: 05/05/2011
• Est. Priority Date: 05/04/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Bhushan, Naga, Montojo, Juan, Chen, Wanshi, Gaal, Peter, Damnjanovic, Jelena M.
• Granted Patent: US 8,583,160 B2
• Time in Patent Office: Days
• US Class Current: 455/127.1
• 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 52/242 taking into account path loss
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/30 using constraints in the total amount of available transmission power
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity

Abstract

Certain aspects of the present disclosure provide closed loop and open loop power control techniques for each antenna of the user equipment (UE). The access point may measure the received signals from each antenna of the user equipment, calculate a power adjustment parameter for each antenna of the UE, and transmit the parameters to the UE. The UE may use the adjustment parameters to determine the transmit power value for each antenna. In addition, the UE may measure the path loss for each antenna and update the transmit power per antenna based on the path loss and other parameters.

Claims

1. A method for wireless communications, comprising:

receiving power adjustment parameters for a subset of antennas;

calculating values of transmit power for the subset of antennas using the received power adjustment parameter associated with each of the antennas; and

transmitting signals from the subset of antennas using power equal to the calculated value of transmit power.

2. The method of claim 1, further comprising:

adjusting the calculated value of transmit power for the subset of antennas based on the value of path loss in signals received by each antenna.

3. The method of claim 1, further comprising:

determining the subset of antennas from which to transmit signals based at least on an optimization of power consumption.

4. The method of claim 1, further comprising:

receiving information about the subset of antennas;

calculating values of transmit power for the subset of antennas using the received information about the subset of antennas and power adjustment parameter associated with each of the antennas; and

adjusting the subset of antennas from which to transmit signals and the transmit power for the subset of antennas based on the calculated values.

5. The method of claim 1, wherein N_T power adjustment parameters are received for N_T antennas, one for each antenna.

6. The method of claim 1, wherein N_T−

1 power adjustment parameters are received for N_T−

1 antennas, relative to one of the antennas that is not included in the N_T−

1 antennas.

7. The method of claim 1, wherein a common power adjustment parameter for all the antennas and N_T relative power adjustment parameters, one for each of the N_T antennas are received, wherein the transmit power per antenna is calculated based on both the common power adjustment parameter and the relative power adjustment parameter.

8. The method of claim 7, wherein the dynamic range of the common power adjustment parameter is larger than the dynamic range of the relative power adjustment parameters.

9. The method of claim 7, wherein the rate of update for the common power adjustment parameter and the relative power adjustment parameters are different.

10. The method of claim 7, wherein the granularity of the common power adjustment parameter and the relative power adjustment parameters are different.

11. A method for wireless communications, comprising:

transmitting power headroom information about a subset of antennas used for transmission including individual power headroom information for a plurality of transmit antennas, wherein the power headroom information comprises a difference between a current transmit power of each antenna and a maximum transmit power.

12. A method for wireless communications, comprising:

performing measurements on the signals received from a subset of antennas of an apparatus;

calculating a plurality of power adjustment parameters, one for each antenna in the subset of antennas of the apparatus based on the measurements; and

transmitting the power adjustment parameters for the subset of the antennas of the apparatus to calibrate the corresponding antenna(s) of the apparatus.

13. The method of claim 12, further comprising:

determining the subset of antennas from which to transmit signals by the apparatus based at least on the power headroom information transmitted by the apparatus, wherein the power headroom information comprises a difference between a current transmit power of each antenna and the maximum transmit power; and

transmitting information about subset of antennas to the apparatus.

14. The method of claim 12, wherein calculating a plurality of power adjustment parameters comprises:

calculating the power adjustment values for a different subset of antennas of the apparatus at each processing interval to cover all of the antennas of the apparatus in a plurality of processing intervals.

15. The method of claim 12, wherein the adjustment parameters are transmitted by radio resource control (RRC) signaling.

16. The method of claim 12, further comprising:

receiving a plurality of values of transmit power for a subset of antennas of the apparatus; and

updating the power adjustment parameters for the subset of antennas of the apparatus based on the received value of transmit power for those antennas.

17. The method of claim 12, wherein the plurality of power adjustment parameters are calculated based at least on the power headroom report transmitted by the apparatus.

18. The method of claim 12, further comprising:

determining the subset of antennas from which to transmit signals by the apparatus to reduce power consumption of the apparatus; and

transmitting information about the subset of antennas to the apparatus.

19. The method of claim 18, further comprising:

determining the subset of antennas from which to transmit signals by the apparatus based at least on a power headroom report received from the apparatus.

20. An apparatus for wireless communications, comprising:

logic for receiving power adjustment parameters for a subset of antennas;

logic for calculating values of transmit power for the subset of antennas using the received power adjustment parameter associated with each of the antennas; and

logic for transmitting signals from the subset of antennas using power equal to the calculated value of transmit power.

21. The apparatus of claim 20, further comprising:

logic for adjusting the calculated value of transmit power for the subset of antennas based on the value of path loss in signals received by each antenna.

22. The apparatus of claim 20, further comprising:

logic for determining the subset of antennas from which to transmit signals based at least on an optimization of power consumption.

23. The apparatus of claim 20, further comprising:

logic for receiving information about the subset of antennas;

logic for calculating values of transmit power for the subset of antennas using the received information about the subset of antennas and power adjustment parameter associated with each of the antennas; and

logic for adjusting the subset of antennas from which to transmit signals and the transmit power for the subset of antennas based on the calculated values.

24. The apparatus of claim 20, wherein N_T power adjustment parameters are received for N_T antennas, one for each antenna.

25. The apparatus of claim 20, wherein N_T−

1 power adjustment parameters are received for N_T−

1 antennas, relative to one of the antennas that is not included in the N_T−

1 antennas.

26. The apparatus of claim 20, wherein a common power adjustment parameter for all the antennas and N_T relative power adjustment parameters, one for each of the N_T antennas are received, wherein the transmit power per antenna is calculated based on both the common power adjustment parameter and the relative power adjustment parameter.

27. The apparatus of claim 26, wherein the dynamic range of the common power adjustment parameter is larger than the dynamic range of the relative power adjustment parameters.

28. The apparatus of claim 26, wherein the rate of update for the common power adjustment parameter and the relative power adjustment parameters are different.

29. The apparatus of claim 26, wherein the granularity of the common power adjustment parameter and the relative power adjustment parameters are different.

30. An apparatus for wireless communications, comprising:

logic for transmitting power headroom information about a subset of antennas used for transmission including individual power headroom information for a plurality of transmit antennas, wherein the power headroom information comprises a difference between a current transmit power of each antenna and a maximum transmit power.

31. An apparatus for wireless communications, comprising:

logic for performing measurements on the signals received from a subset of antennas of an apparatus;

logic for calculating a plurality of power adjustment parameters, one for each antenna in the subset of antennas of the apparatus based on the measurements; and

logic for transmitting the power adjustment parameters for the subset of the antennas of the apparatus to calibrate the corresponding antenna(s) of the apparatus.

32. The apparatus of claim 31, further comprising:

logic for determining the subset of antennas from which to transmit signals by the apparatus based at least on the power headroom information transmitted by the apparatus, wherein the power headroom information comprises a difference between a current transmit power of each antenna and the maximum transmit power; and

logic for transmitting information about subset of antennas to the apparatus.

33. The apparatus of claim 31, wherein calculating a plurality of power adjustment parameters comprises:

calculating the power adjustment values for a different subset of antennas of the apparatus at each processing interval to cover all of the antennas of the apparatus in a plurality of processing intervals.

34. The apparatus of claim 31, wherein the adjustment parameters are transmitted by radio resource control (RRC) signaling.

35. The apparatus of claim 31, further comprising:

logic for receiving a plurality of values of transmit power for a subset of antennas of the apparatus;

logic for updating the power adjustment parameters for the subset of antennas of the apparatus based on the received value of transmit power for those antennas.

36. The apparatus of claim 31, wherein the plurality of power adjustment parameters are calculated based at least on the power headroom report transmitted by the apparatus.

37. The apparatus of claim 31, further comprising:

logic for determining the subset of antennas from which to transmit signals by the apparatus to reduce power consumption of the apparatus; and

logic for transmitting information about the subset of antennas to the apparatus.

38. The apparatus of claim 37, further comprising:

logic for determining the subset of antennas from which to transmit signals by the apparatus based at least on a power headroom report received from the apparatus.

39. An apparatus for wireless communications, comprising:

means for receiving power adjustment parameters for a subset of antennas;

means for calculating values of transmit power for the subset of antennas using the received power adjustment parameter associated with each of the antennas; and

means for transmitting signals from the subset of antennas using power equal to the calculated value of transmit power.

40. An apparatus for wireless communications, comprising:

means for transmitting power headroom information about a subset of antennas used for transmission including individual power headroom information for a plurality of transmit antennas, wherein the power headroom information comprises a difference between a current transmit power of each antenna and a maximum transmit power.

41. An apparatus for wireless communications, comprising:

means for performing measurements on the signals received from a subset of antennas of an apparatus;

means for calculating a plurality of power adjustment parameters, one for each antenna in the subset of antennas of the apparatus based on the measurements; and

means for transmitting the power adjustment parameters for the subset of the antennas of the apparatus to calibrate the corresponding antenna(s) of the apparatus.

42. A computer-program product for wireless communications, comprising a computer readable medium having instructions stored thereon, the instructions being executable by one or more processors and the instructions comprising:

instructions for receiving power adjustment parameters for a subset of antennas;

instructions for calculating values of transmit power for the subset of antennas using the received power adjustment parameter associated with each of the antennas; and

instructions for transmitting signals from the subset of antennas using power equal to the calculated value of transmit power.

43. A computer-program product for wireless communications, comprising a computer readable medium having instructions stored thereon, the instructions being executable by one or more processors and the instructions comprising:

instructions for transmitting power headroom information about a subset of antennas used for transmission including individual power headroom information for a plurality of transmit antennas, wherein the power headroom information comprises a difference between a current transmit power of each antenna and a maximum transmit power.

44. A computer-program product for wireless communications, comprising a computer readable medium having instructions stored thereon, the instructions being executable by one or more processors and the instructions comprising:

instructions for performing measurements on the signals received from a subset of antennas of an apparatus;

instructions for calculating a plurality of power adjustment parameters, one for each antenna in the subset of antennas of the apparatus based on the measurements; and

instructions for transmitting the power adjustment parameters for the subset of the antennas of the apparatus to calibrate the corresponding antenna(s) of the apparatus.

45. An apparatus for wireless communications, comprising at least one processor configured to:

receive power adjustment parameters for a subset of antennas;

calculate values of transmit power for the subset of antennas using the received power adjustment parameter associated with each of the antennas; and

transmit signals from the subset of antennas using power equal to the calculated value of transmit power.

46. An apparatus for wireless communications, comprising at least one processor configured to:

transmit power headroom information about a subset of antennas used for transmission including individual power headroom information for a plurality of transmit antennas, wherein the power headroom information comprises a difference between a current transmit power of each antenna and a maximum transmit power.

47. An apparatus for wireless communications, comprising at least one processor configured to:

perform measurements on the signals received from a subset of antennas of an apparatus;

calculate a plurality of power adjustment parameters, one for each antenna in the subset of antennas of the apparatus based on the measurements; and

transmit the power adjustment parameters for the subset of the antennas of the apparatus to calibrate the corresponding antenna(s) of the apparatus.