Method and device for transmitting synchronization signal for device-to-device communication

Patent metadata

Field	Value
Publication number	US-2017245227-A1
Application number	US-201515310091-A
Country	US
Kind code	A1
Filing date	May 11, 2015
Priority date	May 9, 2014
Publication date	Aug 24, 2017
Grant date	—

Abstract

The present invention relates to a communication technique for converging IoT technology with a 5 G communication system for supporting a higher data transmission rate than that of a 4 G system and subsequent systems, and a system thereof. The present invention can be applied to intelligent services on the basis of 5 G communication technology and IoT-related technology (for example, smart home, smart building, smart city, smart car or connected car, health care, digital education, retail, security, and safety related services and the like). The present invention provides a method and a device for transmitting a synchronization signal for device-to-device (D 2 D) communication. According to the present invention, a first terminal receives a D 2 D synchronization signal (D 2 DSS) and a physical D 2 D synchronization channel (PD 2 DSCH) corresponding to the D 2 DSS from a second terminal, and transmits the D 2 DSS to the second terminal according to a method preassigned with the second terminal so as to indicate that the first terminal has successfully received the D 2 DSS or the PD 2 DSCH.

First claim

What is claimed is:

1 . A method for transmitting a synchronization signal for Device-to-Device (D2D) communication, the method comprising:
receiving, by a first UE, a D2D synchronization signal (D2DSS) and a physical D2D synchronization channel (PD2DSCH) corresponding to the D2DSS from a second UE, and transmitting the D2DSS to the second UE according to a method pre-arranged with the second UE so as to indicate that the first UE has successfully received the D2DSS or the PD2DSCH.

2 . The method of claim 1 , wherein transmitting of the D2DSS to the second UE comprises: transmitting, by the first UE, both the D2DSS and the PD2DSCH to the second UE in order to notify that the first UE has successfully received both the D2DSS and the PD2DSCH.

3 . The method of claim 1 , wherein transmitting of the D2DSS to the second UE comprises: transmitting, by the first UE, the D2DSS to the second UE, using a pre-arranged sequence or resource.

4 . The method of claim 1 , further comprising:
acquiring, by the first UE, transmission power information of the D2DSS and transmission power information of the PD2DSCH from the received PD2DSCH, and estimating a path loss value between the second UE and the first UE on a basis of the received PD2DSCH; and setting, by the first UE, the transmission power of the D2DSS, this is transmitted to the second UE, on the basis of the acquired transmission power information and the estimated path loss value.

5 . A method for transmitting a synchronization signal for device-to-device (D2D) communication, the method comprising:
transmitting, by a first UE, a D2D synchronization signal (D2DSS) and a physical D2D synchronization channel (PD2DSCH) corresponding to the D2DSS to a second terminal; and determining, by the first UE, whether the D2DSS and PD2DSCH have been successfully transmitted depending on whether the D2DSS is received from a second UE, and transmitting a result of determination to a base station.

6 . The method of claim 5 , wherein the first UE transmits the result of determination to the base station, by using Uplink Control Information (UCI) or a predetermined bit of a Medium Access Control (MAC) payload.

7 . The method of claim 5 , wherein the first UE transmits, when a random access procedure is performed, the determination result to the base station.

8 . The method of claim 5 , further comprising:
transmitting, by the first UE, the determination result to the base station, then receiving, from the base station, a command for adjusting a transmission power of the D2DSS and PD2DSCH, and then adjusting the transmission power of the D2DSS and PD2DSCH according to the command.

9 . The method of claim 5 , further comprising: adjusting, by the first UE, a transmission power of the D2DSS and PD2DSCH on the basis of a predetermined rule according to the determination result.

10 . The method of claim 5 , further comprising: when it is determined that the D2DSS and PD2DSCH have been successfully transmitted, stopping, by the first UE, a transmission of the PD2DSCH and D2DSS.

11 . An apparatus for transmitting a synchronization signal for device-to-device (D2D) communication, the apparatus comprising:
a transceiver unit configured to receive, from another UE, a D2D synchronization signal (D2DSS) and a physical D2D synchronization channel (PD2DSCH) corresponding to the D2DSS, and transmit the D2DSS to the other UE according to a method pre-arranged with the other UE so as to indicate that the D2DSS or the PD2DSCH has been successfully received; and a controller configured to control an operation of the transceiver unit.

12 . The apparatus of claim 11 , wherein the transceiver unit transmits both the D2DSS and the PD2DSCH to the other UE so as to notify that both the D2DSS and the PD2DSCH have been successfully received.

13 . The apparatus of claim 11 , wherein the transceiver unit transmits the D2DSS to the other UE, using a pre-arranged sequence or resource.

14 . The apparatus of claim 11 , wherein the controller is configured to acquire, from the received PD2DSCH, transmission power information of the D2DSS and the transmission power information of the PD2DSCH, estimate a path loss value with the other UE on a basis of the received PD2DSCH, and set the transmission power of the D2DSS which is transmitted to the other UE on the basis of the acquired transmission power information and the estimated path loss value.

15 . An apparatus for transmitting a synchronization signal for device-to-device (D2D) communication, the apparatus comprising:
a transceiver unit configured to transmit, to another terminal, a D2D synchronization signal (D2DSS) and a physical D2D synchronization channel (PD2DSCH) corresponding to the D2DSS, receive the D2DSS from the other terminal, and transmit, to a base station, whether the D2DSS and the PD2DSCH have been successfully transmitted; and a controller configured to determine whether the D2DSS and the PD2DSCH have been successfully transmitted depending on whether the D2DSS is received from the other terminal and control an operation of the transceiver unit.

16 . The apparatus of claim 15 , wherein the transceiver unit transmits a result of determination to the base station, by using Uplink Control Information (UCI) or a predetermined bit of a Medium Access Control (MAC) payload.

17 . The apparatus of claim 15 , wherein, when a random access procedure is performed, the transceiver unit transmits a result of determination to the base station.

18 . The apparatus of claim 15 , wherein the transceiver unit transmits a result of determination to the base station, and then receives, from the base station, a command for adjusting a transmission power of the D2DSS and PD2DSCH, and
the controller adjusts the transmission power of the D2DSS and PD2DSCH according to the command.

19 . The apparatus of claim 15 , wherein the controller adjusts a transmission power of the D2DSS and PD2DSCH based on a predetermined rule according to a result of determination.

20 . The apparatus of claim 15 , wherein, when it is determined that the D2DSS and PD2DSCH have been successfully transmitted, the controller controls the transceiver unit to stop a transmission of the PD2DSCH and D2DSS.

Assignees

• Samsung Electronics Co Ltd
• Samsung Electronics Co Ltd

Inventors

• Jeong Cheol
• Ryu Hyun-Seok
• Park Seung-Hoon
• Xue Peng
• Yu Hyun-Kyu
• Choi Sang-Won

Classifications

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title

• H04W72/0413

  Electricity · mapped topic

• H04W52/242

  taking into account path loss · CPC title

• H04W56/001 Primary

  Synchronization between nodes · CPC title

• H04W52/383

  power control in peer-to-peer links · CPC title