User equipment power level selection for downlink transmissions

• US 9,854,536 B2
• Filed: 08/03/2015
• Issued: 12/26/2017
• Est. Priority Date: 08/03/2015
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Chandrasekhar, Vikram, Madan, Ritesh K., Nabar, Rohit Umesh, Shirali, Kedar Durgadas
• Primary Examiner(s): Yao, Kwang B
• Assistant Examiner(s): NGO, NGUYEN HOANG
• Application Number:
  US14/816,990
• Publication Number:
  US 20170041885A1
• Time in Patent Office: 876 Days
• Field of Search: 370252, 370312, 370328, 370329, 370332
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/225 Calculation of statistics, e.g. average, variance
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/281 taking into account user or data type priority
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/346 distributing total power among users or channels

Abstract

An example method is provided in one example embodiment and includes receiving an indication of an average signal power for a downlink connection between a cell and each of a plurality of user equipment devices associated with the cell, receiving an indication of an average interference measurement on the downlink connection between the cell and each of the plurality of user equipment devices associated with the cell, and computing an average spectral efficiency for each of the plurality of user equipment devices based upon the respective average signal power and average interference measurement. The method further includes determining a transmission power level from among a plurality of available transmission power levels for one or more downlink resources for each of the plurality of user equipment devices based upon the computed average spectral efficiency for each of the plurality of user equipment devices.

Claims

1. A method, comprising:

receiving an indication of an average signal power for a downlink connection between a cell and each of a plurality of user equipment devices associated with the cell;

receiving an indication of an average interference measurement on the downlink connection between the cell and each of the plurality of user equipment devices associated with the cell;

computing an average spectral efficiency for each of the plurality of user equipment devices based upon the respective indications of average signal power and average interference measurement; and

determining a transmission power level from among a plurality of available transmission power levels for one or more downlink resources for each of the plurality of user equipment devices based upon the computed average spectral efficiency for each of the plurality of user equipment devices;

wherein the transmission power level is chosen for a particular one of the plurality of user equipment devices from a plurality of available transmission power levels such that the average spectral efficiency of user equipment devices with a higher power level is higher than the average spectral efficiency if the particular user equipment device shares resources with other user equipment devices that are served by resources with a lower power level.

2. The method of claim 1, wherein the average spectral efficiency for each user equipment device is computed as a function of the average signal power divided by the average spectral efficiency for each user equipment device.

3. The method of claim 1, wherein the available transmission power levels include a first power level and a second power level, the second power level being greater than the first power level.

4. The method of claim 3, wherein user equipment devices that are interior to the cell are served at the first power level and the remaining user equipment devices within the cell are served at the second power level.

5. The method of claim 3, wherein determining the transmission power level includes:

ordering the plurality of user equipment devices in decreasing order of the computed spectral efficiency for each user equipment device;

determining whether each of the ordered plurality of user equipment devices meets a first condition for being assigned the second power level;

iteratively assigning the second power level for each of the ordered plurality of user equipment devices that meet the first condition; and

iteratively assigned the first power level for each of the plurality of user equipment devices that does not meet the first condition.

6. The method of claim 5, wherein the first condition includes if the particular user equipment device UE_i of the ordered user equipment devices UE₁ . . . UE_N receives a higher rate when it shares resources with user equipment devices UE₁ . . . UE_i-1 with the second power level than if the particular user equipment device UE_i is assigned the first power level.

7. The method of claim 3, wherein user equipment devices that are at an edge of the cell are served at the second power level and the remaining user equipment devices within the cell are served at the first power level.

8. The method of claim 3, wherein determining the transmission power level includes:

ordering the plurality of user equipment devices in increasing order of signal-to-interference-plus-noise ratio (SINR) within a reuse one portion of the frequency spectrum for each user equipment device;

determining whether each of the ordered plurality of user equipment devices meets a second condition for being assigned the second power level;

iteratively assigning the second power level for each of the ordered plurality of user equipment devices that meet the second condition; and

iteratively assigned the first power level for each of the plurality of user equipment devices that does not meet the second condition.

9. The method of claim 8, wherein the second condition includes if the particular user equipment device UE_i of the ordered user equipment devices UE₁ . . . UE_N receives a greater estimated throughput rate when assigned all resources with the second power level divided by a current index value i is greater than an average spectral efficiency when assigned the second power level multiplied by the total resources with the first power level divided by a function of a total number of user equipment devices and the index value.

10. The method of claim 1, wherein the transmission power level is determined adaptively responsive to a change in channel condition of one or more of the plurality of user equipment devices if an average throughput of the cell will improve by at least a predetermined amount.

11. One or more non-transitory tangible media that includes code for execution and when executed by a processor operable to perform operations comprising:

receiving an indication of an average signal power for a downlink connection between a cell and each of a plurality of user equipment devices associated with the cell;

receiving an indication of an average interference measurement on the downlink connection between the cell and each of the plurality of user equipment devices associated with the cell;

computing an average spectral efficiency for each of the plurality of user equipment devices based upon the respective indications of average signal power and average interference measurement; and

determining a transmission power level from among a plurality of available transmission power levels for one or more downlink resources for each of the plurality of user equipment devices based upon the computed average spectral efficiency for each of the plurality of user equipment devices;

wherein the transmission power level is chosen for a particular one of the plurality of user equipment devices from a plurality of available transmission power levels such that the average spectral efficiency of user equipment devices with a higher power level is higher than the average spectral efficiency if the particular user equipment device shares resources with other user equipment devices that are served by resources with a lower power level.

12. The media of claim 11, wherein the average spectral efficiency for each user equipment device is computed as a function of the average signal power divided by the average spectral efficiency for each user equipment device.

13. The media of claim 11, wherein the available transmission power levels include a first power level and a second power level, the second power level being greater than the first power level.

14. The media of claim 13, wherein determining the transmission power level includes:

ordering the plurality of user equipment devices in decreasing order of the computed spectral efficiency for each user equipment device;

determining whether each of the ordered plurality of user equipment devices meets a first condition for being assigned the second power level;

iteratively assigning the second power level for each of the ordered plurality of user equipment devices that meet the first condition; and

iteratively assigned the first power level for each of the plurality of user equipment devices that does not meet the first condition.

15. The media of claim 13, wherein user equipment devices that are at an edge of the cell are served at the second power level and the remaining user equipment devices within the cell are served at the first power level.

16. The media of claim 13, wherein determining the transmission power level includes:

ordering the plurality of user equipment devices in increasing order of signal-to-interference-plus-noise ratio (SINR) within a reuse one portion of the frequency spectrum for each user equipment device;

determining whether each of the ordered plurality of user equipment devices meets a second condition for being assigned the second power level;

iteratively assigning the second power level for each of the ordered plurality of user equipment devices that meet the second condition; and

iteratively assigned the first power level for each of the plurality of user equipment devices that does not meet the second condition.

17. An apparatus, comprising:

a memory element configured to store data,

a processor operable to execute instructions associated with the data, and

at least one module being configured to;

receive an indication of an average signal power for a downlink connection between a cell and each of a plurality of user equipment devices associated with the cell;

receive an indication of an average interference measurement on the downlink connection between the cell and each of the plurality of user equipment devices associated with the cell;

compute an average spectral efficiency for each of the plurality of user equipment devices based upon the respective indications of average signal power and average interference measurement; and

determine a transmission power level from among a plurality of available transmission power levels for one or more downlink resources for each of the plurality of user equipment devices based upon the computed average spectral efficiency for each of the plurality of user equipment devices;

wherein the available transmission power levels include a first power level and a second power level, the second power level being greater than the first power level;

wherein determining the transmission power level includes;

ordering the plurality of user equipment devices in decreasing order of the computed spectral efficiency for each user equipment device;

determining whether each of the ordered plurality of user equipment devices meets a first condition for being assigned the second power level;

iteratively assigning the second power level for each of the ordered plurality of user equipment devices that meet the first condition; and

iteratively assigned the first power level for each of the plurality of user equipment devices that does not meet the first condition.

18. An apparatus, comprising:

a memory element configured to store data,

a processor operable to execute instructions associated with the data, and

at least one module being configured to;

receive an indication of an average signal power for a downlink connection between a cell and each of a plurality of user equipment devices associated with the cell;

receive an indication of an average interference measurement on the downlink connection between the cell and each of the plurality of user equipment devices associated with the cell;

compute an average spectral efficiency for each of the plurality of user equipment devices based upon the respective indications of average signal power and average interference measurement; and

determine a transmission power level from among a plurality of available transmission power levels for one or more downlink resources for each of the plurality of user equipment devices based upon the computed average spectral efficiency for each of the plurality of user equipment devices;

wherein the available transmission power levels include a first power level and a second power level, the second power level being greater than the first power level;

wherein determining the transmission power level includes;

ordering the plurality of user equipment devices in increasing order of signal-to interference-plus-noise ratio (SINR) within a reuse one portion of the frequency spectrum for each user equipment device;

determining whether each of the ordered plurality of user equipment devices meets a second condition for being assigned the second power level;

iteratively assigning the second power level for each of the ordered plurality of user equipment devices that meet the second condition; and

iteratively assigned the first power level for each of the plurality of user equipment devices that does not meet the second condition.