Power control of device-to-device synchronization signal

Patent metadata

Field	Value
Publication number	US-2016255597-A1
Application number	US-201514762680-A
Country	US
Kind code	A1
Filing date	Mar 13, 2015
Priority date	Mar 18, 2014
Publication date	Sep 1, 2016
Grant date	—

Abstract

A method and system for setting a power of a secondary device-to-device synchronization signal, SD2DSS, by a first wireless device to enable a second wireless device to synchronize timing of the second wireless device to a timing of the first wireless device are disclosed. According to one aspect, a method includes determining power of a first signal transmitted by the first wireless device, and setting the power of the SD2DSS based on the power of the first signal.

First claim

1 . A method of setting a power of a secondary device-to-device synchronization signal, SD2DSS, by a first wireless device to enable a second wireless device to synchronize timing of the second wireless device to a timing derived from the first wireless device, the method comprising:
determining power of a first signal transmitted by the first wireless device; and setting the power of the SD2DSS based on the power of the first signal.

2 . The method of claim 1 , wherein the first signal is a primary device to device synchronization signal, PD2DSS.

3 . The method of claim 2 , wherein the PD2DSS includes a Zadoff-Chu, ZC, sequence and the SD2DSS includes an M sequence.

4 . The method of claim 2 , wherein the power of the SD2DSS is set to be less than the power of the PD2DSS by a configurable power offset.

5 . The method of claim 4 , further comprising receiving the configurable power offset via a base station.

6 . The method of claim 2 , wherein the power of the SD2DSS is the minimum of a nominal value of the power of the PD2DSS and a power threshold.

7 . The method of claim 1 , wherein the set power of the SD2DSS is adjusted only when the power of the first signal exceeds a predetermined amount.

8 . The method of claim 1 , wherein a same circuitry generates the SD2DSS and a secondary synchronization signal, SSS.

9 . A wireless device configured to set a power of a secondary device-to-device synchronization signal, SD2DSS, to enable a second wireless device to synchronize timing of the second wireless device to a timing of the wireless device, the wireless device comprising:
a processor; and a memory, the memory containing instructions executable by the processor, the instructions when executed configure the processor to:
determine power of a first signal transmitted by the wireless device; and
set the power of the SD2DSS based on the power of the first signal.

10 . The wireless device of claim 9 wherein the first signal is a primary device to device synchronization signal, PD2DSS.

11 . The wireless device of claim 10 , wherein the PD2DSS includes a Zadoff-Chu, ZC, sequence and the SD2DSS includes an M sequence.

12 . The wireless device of claim 10 , wherein the power of the SD2DSS is set to be less than the power of the PD2DSS by a configurable power offset.

13 . The wireless device of claim 12 , further comprising a transceiver configured to receive the configurable power offset via a base station.

14 . The wireless device of claim 10 , wherein the power of the SD2DSS is a minimum of a nominal value of the power of the PD2DSS and a power threshold.

15 . A wireless device, comprising:
a signal power determiner module configured to determine power of a first signal; and a secondary device to device synchronization signal, SD2DSS, power setting module configured to set power of the SD2DSS based on the determined power of the first signal.

16 . The wireless device of claim 15 , wherein the first signal is a primary device to device synchronization signal, PD2DSS (S 104 ).

17 . The wireless device of claim 16 , wherein the PD2DSS includes a Zadoff-Chu, ZC sequence and the SD2DSS includes an M sequence.

18 . The wireless device of claim 16 , wherein the power of the SD2DSS is a minimum of a nominal value of the power of the PD2DSS and a power threshold.

19 . A method of determining and transmitting one of a power offset and a power threshold to a wireless device, the method comprising:
determining at least one of a power offset and a power threshold for setting a power of a secondary device to device synchronization signal, SD2DSS, by a wireless device; and transmitting at least one of the power offset and the power threshold to the wireless device.

20 . A network node, comprising:
a processor; a memory containing instructions that when executed by the processor configure the processor to determine at least one of a power offset and a power threshold for setting a power of secondary device to device synchronization signal, SD2DSS by a wireless device; a communication interface configured to transmit at least one of the power offset and the power threshold to the wireless device; and the memory configured to store the at least one of the power offset and the power threshold.

21 . A network node, comprising:
a power offset determiner module configured to determine a power offset to be used by a wireless device, to set a secondary device to device synchronization signal, SD2DSS; and a power threshold determiner module configured to determine a power threshold to be used by the wireless device to determine whether to set a power of the SD2DSS.

Assignees

• Ericsson Telefon Ab L M

Inventors

• Zhao Zhenshan
• Sorrentino Stefano

Classifications

• H04W56/0015

  one node acting as a reference for the others · CPC title

• H04W52/36

  with a discrete range or set of values, e.g. step size, ramping or offsets · CPC title

• H04W52/322 Primary

  Power control of broadcast channels · CPC title

• H04L27/2614

  Peak power aspects · CPC title

• H04W4/70

  Services for machine-to-machine communication [M2M] or machine type communication [MTC] · CPC title