Apparatus and method for adjustment of transmitter power in a system

• US 10,595,282 B2
• Filed: 10/30/2017
• Issued: 03/17/2020
• Est. Priority Date: 07/26/2010
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Forrester, John, Guckian, Paul A., Lu, Lin, Shahidi, Reza, Mahajan, Amit, Hamdy, Walid M., Ngai, Francis M.
• Primary Examiner(s): Jia, Xin
• Application Number:
  US15/797,470
• Publication Number:
  US 20180070320A1
• Time in Patent Office: 869 Days
• CPC Class Codes: H04W 52/226 using past references to control power, e.g. look-up-table
• CPC Class Codes: H04W 52/281 taking into account user or data type priority
• 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 propose methods for determining power level of one or more transmitters based on a power level of a primary transmitter when the transmitters are located in close proximity of each other. The power levels may be determined such that a combined power of all the transmitters is compliant with regulatory radio frequency (RF) safety requirements. For certain aspects, power level of the lower priority transmitters may be determined utilizing one or more look-up tables. For another aspect, power level of the lower priority transmitters may be calculated using an algorithm based on the power level of the priority transmitter. In aspects, the power level of lower priority transmitters and the time duration for which the transmitters are active may be selected dynamically so that the time averaged power of the transmitters for a defined period of time falls below the RF exposure limit.

Claims

1. A method for wireless communications, comprising:

identifying a first transmitter power level for a first transmitter unit to transmit signals over a wireless network;

selecting a transmitter power back-off value for a second transmitter unit, from a look-up table (LUT) including a plurality of predetermined back-off values for the second transmitter unit, each of the predetermined back-off values associated with a transmitter power level or a range of transmitter power levels for the first transmitter unit, wherein;

the selecting comprises selecting the transmitter power back-off value for the second transmitter unit in the LUT corresponding to the identified first transmitter power level for the first transmitter unit; and

the first and the second transmitter units operate near simultaneously using one or more transmit antennas; and

adjusting a transmitter power level of the second transmitter unit to transmit signals over a wireless network by applying the selected transmitter power back-off value, wherein a total of the transmitter power levels of the first and the second transmitter units is less than or equal to an allowable total transmitter power level based on a radio frequency (RF) exposure limit.

2. The method of claim 1, wherein the transmitter power levels or range of transmitter power levels for the first transmitter unit in the LUTs are further associated with a plurality of predetermined transmitter power back-off values for a third transmitter unit, and wherein the second transmitter unit and the third transmitter unit transmit using with a different transmission frequency.

3. The method of claim 2, further comprising:

selecting at least a second transmitter power back-off value for at least the third transmitter unit from the LUT corresponding to the first transmitter power level, wherein the first, second, and third transmitter units operate near simultaneously using one or more transmit antennas; and

adjusting at least a transmitter power level of at least the third transmitter unit based on at by applying the selected second transmitter power back-off value, wherein a total of the transmitter power levels of the first, second, and third transmitter units is less than or equal to the allowable total transmitter power level.

4. The method of claim 1, wherein the second transmitter unit is associated with a lower priority than the first transmitter unit.

5. The method of claim 4, further comprising:

determining the priority of the first and the second transmitter units based on one or more of data priorities, available frequency bands, load of a network, radio frequency conditions, available technologies, and cost of data connection.

6. The method of claim 1, wherein the first and the second transmitter units are located on different apparatuses.

7. An apparatus for wireless communications, comprising:

means for identifying a first transmitter power level for a first transmitter unit to transmit signals over a wireless network;

means for selecting a transmitter power back-off value for a second transmitter unit, from a look-up table (LUT) including a plurality of predetermined back-off values for the second transmitter unit, each of the predetermined back-off values associated with a transmitter power level or a range of transmitter power levels for the first transmitter unit, wherein;

the selecting comprises selecting the transmitter power back-off value for the second transmitter unit in the LUT corresponding to the identified first transmitter power level for the first transmitter unit; and

the first and the second transmitter units operate near simultaneously using one or more transmit antennas; and

means for adjusting a transmitter power level of the second transmitter unit to transmit signals over a wireless network by applying the selected transmitter power back-off value, wherein a total of the transmitter power levels of the first and the second transmitter units is less than or equal to an allowable total transmitter power level based on a radio frequency (RF) exposure limit.

8. The apparatus of claim 7, wherein the transmitter power levels or range of transmitter power levels for the first transmitter unit in the LUTs are further associated with a plurality of-predetermined transmitter power back-off values for a third transmitter unit, and wherein the second transmitter unit and the third transmitter unit transmit using with a different transmission frequency.

9. The apparatus of claim 8, further comprising:

means for selecting at least a second transmitter power back-off value for at least the third transmitter unit from the LUT corresponding to the first transmitter power level, wherein the first, second, and third transmitter units operate near simultaneously using one or more transmit antennas; and

means for adjusting at least a transmitter power level of at least the third transmitter unit based on at by applying the selected second transmitter power back-off value, wherein a total of the transmitter power levels of the first, second, and third transmitter units is less than or equal to the allowable total transmitter power level.

10. The apparatus of claim 7, wherein the second transmitter unit is associated with a lower priority than the first transmitter unit.

11. The apparatus of claim 10, further comprising:

means for determining priority of the first and the second transmitter units based on one or more of data priorities, available frequency bands, load of a network, radio frequency conditions, available technologies, and cost of data connection.

12. The apparatus of claim 7, wherein the first and the second transmitter units are located on different apparatuses.

13. An apparatus for wireless communications, comprising:

at least one processor coupled with a memory and configured to;

identify a first transmitter power level for a first transmitter unit to transmit signals over a wireless network;

select a transmitter power back-off value for a second transmitter unit, from a look-up table (LUT) including a plurality of predetermined back-off values for the second transmitter unit, each of the predetermined back-off values associated with a transmitter power level or a range of transmitter power levels for the first transmitter unit, wherein;

the selecting comprises selecting the transmitter power back-off value for the second transmitter unit in the LUT corresponding to the identified first transmitter power level for the first transmitter unit; and

the first and the second transmitter units operate near simultaneously using one or more transmit antennas; and

adjust a transmitter power level of the second transmitter unit to transmit signals over a wireless network by applying the selected transmitter power back-off value, wherein a total of the transmitter power levels of the first and the second transmitter units is less than or equal to an allowable total transmitter power level based on a radio frequency (RF) exposure limit.

14. The apparatus of claim 13, wherein the transmitter power levels or range of transmitter power levels for the first transmitter unit in the LUTs are further associated with a plurality of-predetermined transmitter power back-off values for a third transmitter unit, and wherein the second transmitter unit and the third transmitter unit transmit using with a different transmission frequency.

15. The apparatus of claim 14, wherein the at least one processor is configured to:

select at least a second transmitter power back-off value for at least the third transmitter unit from the LUT corresponding to the first transmitter power level, wherein the first, second, and third transmitter units operate near simultaneously using one or more transmit antennas; and

adjust at least a transmitter power level of at least the third transmitter unit based on at by applying the selected second transmitter power back-off value, wherein a total of the transmitter power levels of the first, second, and third transmitter units is less than or equal to the allowable total transmitter power level.

16. The apparatus of claim 13, wherein the second transmitter unit is associated with a lower priority than the first transmitter unit.

17. The apparatus of claim 16, further comprising:

determining priority of the first and the second transmitter units based on one or more of data priorities, available frequency bands, load of a network, radio frequency conditions, available technologies, and cost of data connection.

18. The apparatus of claim 13, wherein the first and the second transmitter units are located on different apparatuses.

19. A non-transitory computer readable medium having computer executable code stored thereon for wireless communication, comprising:

code for identifying a first transmitter power level for a first transmitter unit to transmit a signal over a wireless network;

code for selecting a transmitter power back-off value for a second transmitter unit, from a look-up table (LUT) including a plurality of predetermined back-off values for the second transmitter unit, each of the predetermined back-off values associated with a transmitter power level or a range of transmitter power levels for the first transmitter unit, wherein;

the selecting comprises selecting the transmitter power back-off value for the second transmitter unit in the LUT corresponding to the identified first transmitter power level for the first transmitter unit; and

the first and the second transmitter units operate near simultaneously using one or more transmit antennas; and

code for adjusting a transmitter power level of the second transmitter unit to transmit signals over a wireless network by applying the selected transmitter power back-off value, wherein a total of the transmitter power levels of the first and the second transmitter units is less than or equal to an allowable total transmitter power level based on a radio frequency (RF) exposure limit.

20. The non-transitory computer readable medium of claim 19, wherein the transmitter power levels or range of transmitter power levels for the first transmitter unit in the LUTs are further associated with a plurality of-predetermined transmitter power back-off values for a third transmitter unit, and wherein the second transmitter unit and the third transmitter unit transmit using with a different transmission frequency.

21. The non-transitory computer readable medium of claim 19, wherein the second transmitter unit is associated with a lower priority than the first transmitter unit.

22. The non-transitory computer readable medium of claim 21, further comprising:

code for determining priority of the first and the second transmitter units based on one or more of data priorities, available frequency bands, load of a network, radio frequency conditions, available technologies, and cost of data connection.