METHOD AND DEVICE FOR PERFORMING DEVICE-TO-DEVICE COMMUNICATION IN WIRELESS COMMUNICATION SYSTEM

• US 20150146687A1
• Filed: 04/29/2013
• Published: 05/28/2015
• Est. Priority Date: 04/27/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Hakseong, Seo, Hanbyul
• Granted Patent: US 9,674,760 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/03 Reselecting a link using a direct mode connection
• CPC Class Codes: H04W 36/36 by user or terminal equipment
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 76/14 Direct-mode setup

Abstract

A method for performing device-to-device (D2D) communication in a wireless communication system is provided. A master user equipment sets a D2D link with a slave user equipment. The master user equipment performs D2D communication with the slave user equipment through the D2D link. The master user equipment receives handover information of the slave user equipment from the slave user equipment. The master user equipment transmits the handover information of the slave user equipment to an evolved NodeB of a handover source cell.

Claims

1. A method for performing device-to-device (D2D) communication in a wireless communication system, the method comprising:

establishing, by a master user equipment (UE), a D2D link with a slave UE;

performing, by the master UE, the D2D communication with the slave UE through the D2D link;

receiving, by the master UE from the slave UE, handover information of the slave UE; and

transmitting, by the master UE to a base station of a handover source cell, the handover information of the slave UE.

2. The method of claim 1, wherein the handover information of the slave UE contains a UE identifier (ID) which is used by the slave UE in the handover source cell.

3. The method of claim 2, wherein the UE ID is a cell-radio network temporary identifier (C-RNTI).

4. The method of claim 1, further comprising receiving, by the master UE from the base station of the handover source cell, handover information of a handover target cell.

5. The method of claim 4, wherein the handover information of the handover target cell contains a UE ID which is used by the slave UE in the handover target cell.

6. The method of claim 4, further comprising transmitting, by the master UE to the slave UE, the handover information of the handover target cell.

7. The method of claim 6, wherein the handover information of the handover target cell contains a physical cell ID of the handover target cell.

8. The method of claim 6, wherein the handover information of the handover target cell contains a timing advance value for the handover target cell of the master UE.

9. The method of claim 1, wherein the establishing of the D2D link comprises:

transmitting, by the master UE to the base station of the handover source cell, a request message for a connection of the D2D link, wherein the request message contains a UE ID which is used by the slave UE in the handover source cell;

receiving, by the master UE from the base station of the handover source cell, a physical downlink control channel (PDCCH) order in response to the request message;

transmitting, by the master UE to the slave UE, a random access preamble through a physical random access channel (PRACH) on the basis of the PDCCH order; and

receiving, by the master UE from the slave UE, a response for the random access preamble.

10. A user equipment (UE) for performing device-to-device (D2D) communication with a slave UE in a wireless communication system, the UE comprising:

a reception module for receiving a signal from an external device;

a transmission module for transmitting the signal to the external device; and

a processor for controlling the apparatus having the reception module and the transmission module and configured to;

receive, from the slave UE, handover information of the salve UE; and

transmit, to a base station of a handover source cell, the handover information of the slave UE.

11. The UE of claim 10, wherein the handover information of the slave UE contains a UE identifier (ID) which is used by the slave UE in the handover source cell.

12. The UE of claim 10, wherein the processor receives handover information of a handover target cell from the base station of the handover source cell.

13. The UE of claim 12, wherein the handover information of the handover target cell contains a UE ID which is used by the slave UE in the handover target cell.

14. The UE of claim 12, wherein the processor is configured to transmit, to the slave UE, the handover information of the handover target cell.

15. The UE of claim 14, wherein the handover information of the handover target cell contains a physical cell ID of the handover target cell.

16. The UE of claim 14, wherein the handover information of the handover target cell contains a timing advance value for the handover target cell of the master UE.