Method and device for performing group communication using direct communication between terminals in wireless communication system

• US 9,712,995 B2
• Filed: 12/17/2013
• Issued: 07/18/2017
• Est. Priority Date: 12/20/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seo, Hanbyul, Kim, Byounghoon
• Primary Examiner(s): Choudhry, Samina
• Application Number:
  US14/650,830
• Publication Number:
  US 20150334555A1
• Time in Patent Office: 1,309 Days
• Field of Search: 370254
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 8/186 Processing of subscriber group data
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

The present application discloses a method of performing group communication using user equipment (UE) in a wireless communication system. In particular, the method includes: detecting a first group of discovery signals having a first tier counter value; generating a second group of discovery signals having a second tier counter value by using the first value; and transmitting the second group of discovery signals to another UE, wherein the tier counter indicates a tier value to which the UE belongs based on an initially activated UE or base station in the group communication.

Claims

1. A method for transmitting synchronization signals for a Device-to-Device (D2D) link at a user equipment (UE) in a wireless communication system, the method comprising;

receiving, by the UE, one or more first synchronization signals for the D2D link from one or more first UEs, each of the one or more first synchronization signals providing information on a priority of a corresponding first synchronization signal,

wherein the priority is determined based on whether the corresponding first synchronization signal is from a coverage providing a reception quality equal to or greater than a predetermined level;

selecting, by the UE, one of the one or more first synchronization signals having a highest priority based on the reception quality;

generating, by the UE, a second synchronization signal for the D2D link using the selected first synchronization signal when the reception quality of the selected first synchronization signal is lower than a threshold value; and

transmitting, by the UE, the second synchronization signal to at least one second UE.

2. The method of claim 1, wherein generating the second synchronization signal comprises configuring a priority of the second synchronization signal using the priority of the selected first synchronization signal.

3. The method of claim 1, further comprising:

obtaining a synchronization using the selected first synchronization signal.

4. The method of claim 1, wherein the priority is determined in decreasing order of a number of coverages through which the corresponding first synchronization signal is received.

5. A user equipment (UE) in a wireless communication system, the UE comprising:

a receiver;

a transmitter; and

a processor operatively connected to the receiver and the transmitter, the processor configured to;

receive one or more first synchronization signals for the D2D link from one or more first UEs, each of the one or more first synchronization signals providing information on a priority of a corresponding first synchronization signal,

wherein the priority is determined based on whether the corresponding first synchronization signal is from a coverage providing a reception quality equal to or greater than a predetermined level;

select one of the one or more first synchronization signals having a highest priority based on the reception quality;

generate a second synchronization signal for the D2D link using the selected first synchronization signal when the reception quality of the selected first synchronization signal is lower than a threshold value; and

transmit the second synchronization signal to at least one second UE.

6. The UE of claim 5, wherein the processor configures a priority of the second synchronization signal using the priority of the selected first synchronization signal.

7. The UE of claim 5, wherein the processor obtains a synchronization using the selected first synchronization signal.

8. The UE of claim 5, wherein the priority is determined in decreasing order of a number of coverages through which the corresponding first synchronization signal is received.