System and method for power control command for device-to-device transmissions

Patent metadata

Field	Value
Publication number	US-10588098-B2
Application number	US-201916281719-A
Country	US
Kind code	B2
Filing date	Feb 21, 2019
Priority date	May 8, 2014
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

A transmit power control rule for device-to-device (D2D) transmissions may not be necessary during periods in which no uplink transmissions are scheduled to be received by an enhanced Node B base station (eNB). When uplink transmissions are not scheduled to be received by the eNB, the eNB may send a transmit power control (TPC) command to a D2D capable user equipment (D2D UE) that instructs the D2D UE to perform a D2D transmission at a pre-defined transmit power level (e.g., maximum transmit power level). When uplink transmissions are scheduled to be received the eNB, the eNB may send a TPC command to the D2D UE that instructs the D2D UE to perform a D2D transmission at a transmit power level defined by a power control rule.

First claim

What is claimed is:

1. A method for power control for device-to-device (D2D) communications in a wireless communication network, the method comprising:
sending, by a base station, a first indication to a user equipment (UE), the first indication instructing the UE to perform a first D2D transmission at a pre-defined transmit power level over first time-frequency resources available to carry the first D2D transmission; and
sending, by the base station, a second indication to the UE, the second indication instructing the UE to perform a second D2D transmission at a transmit power level defined by a power control rule over second time-frequency resources available to carry the second D2D transmission, the transmit power level defined by the power control rule being lower than the pre-defined transmit power level.

2. The method of claim 1 , wherein each of the first and second indications is valid for a specific period.

3. The method of claim 2 , wherein the specific period comprises one or more subframes.

4. The method of claim 2 , wherein the specific period is communicated from the base station to the UE via higher layer signaling.

5. The method of claim 1 , wherein parameters of the power control rule are configured by higher layer signaling.

6. The method of claim 1 , wherein the power control rule comprises an open-loop power control rule.

7. The method of claim 1 , wherein the first and second indications are communicated using a downlink control information (DCI) format.

8. The method of claim 7 , wherein the first and second indications are transmitted on a physical downlink control channel (PDCCH).

9. The method of claim 7 , wherein the first and second indications are transmitted on an enhanced physical downlink control channel (EPDCCH).

10. The method of claim 7 , wherein the DCI format associates the first and second indications with the UE by carrying a radio network temporary identifier (RNTI).

11. The method of claim 1 , wherein the power control rule is in accordance with at least one uplink transmission scheduled to be received by the base station over second time-frequency resources available to carry the second D2D transmission.

12. A base station comprising:
a non-transitory memory storage comprising instructions; and
one or more processors in communication with the memory storage, wherein the one or more processors execute the instructions to:
send a first indication to a user equipment (UE), the first indication instructing the UE to perform a first device-to-device (D2D) transmission at a pre-defined transmit power level over first time-frequency resources available to carry the first D2D transmission; and
send a second indication to the UE, the second indication instructing the UE to perform a second D2D transmission at a transmit power level defined by a power control rule over second time-frequency resources available to carry the second D2D transmission, the transmit power level defined by the power control rule being lower than the pre-defined transmit power level.

13. The base station of claim 12 , wherein the first and second indications are communicated using a downlink control information (DCI) format.

14. The base station of claim 13 , wherein the first and second indications are transmitted on a physical downlink control channel (PDCCH).

15. The base station of claim 13 , wherein the first and second indications are transmitted on an enhanced physical downlink control channel (EPDCCH).

16. The base station of claim 13 , wherein the DCI format associates the first and second indications with the UE by carrying a radio network temporary identifier (RNTI).

17. The base station of claim 12 , wherein each of the first and second indications is valid for a specific period.

18. The base station of claim 17 , wherein the specific period comprises one or more subframes.

19. The base station of claim 17 , wherein the specific period is communicated from the base station to the UE via higher layer signaling.

20. The base station of claim 12 , wherein parameters of the power control rule are configured by higher layer signaling.

21. The base station of claim 12 , wherein the power control rule comprises an open-loop power control rule.

22. The base station of claim 12 , wherein the power control rule is in accordance with at least one uplink transmission scheduled to be received by the base station over second time-frequency resources available to carry the second D2D transmission.

Assignees

• Futurewei Technologies Inc

Inventors

• Bagheri Hossein
• Al-Shalash Mazin Ali
• Sartori Philippe
• Soong Anthony C K

Classifications

• H04W52/386

  centralized, e.g. when the radio network controller or equivalent takes part in the power control · CPC title

• H04W52/08

  Closed loop power control · CPC title

• H04W52/243

  taking into account interferences · CPC title

• H04W52/325

  Power control of control or pilot channels · CPC title

• H04W92/18

  between terminal devices · CPC title