Method and apparatus for stopping device-to-device operation in wireless communication system

Patent metadata

Field	Value
Publication number	US-9706341-B2
Application number	US-201414906758-A
Country	US
Kind code	B2
Filing date	Aug 4, 2014
Priority date	Aug 4, 2013
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A method and apparatus for stopping a device-to-device (D 2 D) operation in a wireless communication system is provided. A user equipment (UE) supporting proximity services (ProSe) stops an on-going D 2 D operation if at least one of conditions is satisfied. For example, when the UE detects any cell, when the UE finds a suitable cell, when the UE finds an acceptable cell, when the UE enters a connected state, or when the UE initiates radio resource control (RRC) connection establishment procedure, the UE may stops the on-going D 2 D operation.

First claim

The invention claimed is:

1. A method for stopping, by a user equipment (UE) supporting proximity services (ProSe), a device-to-device (D2D) operation in a wireless communication system, the method comprising:
stopping an on-going D2D operation if the UE belonging to a ProSe group finds an acceptable cell or a suitable cell;
transmitting an indication of leaving the ProSe group to a group owner (GO) of the ProSe group if the D2D operation is stopped, wherein the ProSe group is for public safety; and
leaving the ProSe group,
wherein the acceptable cell is a cell where a limited service is provided, and
wherein the suitable cell is a cell where a regular service is provided.

2. The method of claim 1 , wherein the UE is configured for at least one ProSe group by a network or a server.

3. The method of claim 1 , wherein the D2D operation includes at least one of monitoring a D2D discovery message, transmitting a D2D discovery message, monitoring a D2D communication message, transmitting a D2D communication message, monitoring D2D reference signal or D2D-related message or data from other UE, transmitting D2D reference signal or D2D-related message or data to other UE, or requesting initiation of D2D discovery or D2D communication to a network or other UE.

4. The method of claim 1 , wherein a group identity (ID) of the ProSe group corresponds to the public safety.

5. The method of claim 1 , further comprising:
receiving information on cells near the ProSe group from the GO of the ProSe group.

6. The method of claim 5 , wherein the information on cells includes at least one of frequencies of the cells or IDs of the cells.

7. The method of claim 1 , further comprising:
transmitting a group ID of the ProSe group to a network during connection establishment.

8. The method of claim 1 , further comprising:
initiating, by the UE, a radio resource control (RRC) connection establishment procedure.

9. The method of claim 1 , further comprising:
entering, by the UE, a connected state.

10. A user equipment (UE) for supporting proximity services (ProSe) in a wireless communication system, the UE comprising:
a radio frequency (RF) unit that transmits or receives a radio signal; and
a processor, coupled to the RF unit, that:
stops an on-going D2D operation if the UE belonging to a ProSe group finds an acceptable cell or a suitable cell;
controls the RF unit to transmit an indication of leaving the ProSe group to a group owner (GO) of the ProSe group if the D2D operation is stopped, wherein the ProSe group is for public safety; and
leave the ProSe group,
wherein the acceptable cell is a cell where a limited service is provided, and
wherein the suitable cell is a cell where a regular service is provided.

11. The UE of claim 10 , wherein the UE is configured for at least one ProSe group by a network or a server.

Assignees

• Lg Electronics Inc

Inventors

• Lee Youngdae
• Jung Sunghoon

Classifications

• H04W8/005

  Discovery of network devices, e.g. terminals · CPC title

• H04W76/30

  Connection release · CPC title

• H04W36/06

  Reselecting a communication resource in the serving access point · CPC title

• H04W56/0015

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

• H04W76/14

  Direct-mode setup · CPC title