Method for controlling timing advance for direct communication between terminals in wireless communication system, and apparatus therefor
Disclosed is a method for transmitting a signal by a terminal via a device to device (D2D) link in a wireless communication system. Specifically, the method comprises: a step for receiving information on a timing advance (TA) value from a base station; a step for transmitting the TA value to a counterpart terminal via a first D2D control channel; and a step for transmitting a D2D data channel based on the first D2D control channel to the counterpart terminal by applying the TA, wherein the TA is not applied to the first D2D control channel. In particular, when the information on the updated TA value is received from the base station, it is desirable to transmit the D2D data channel based on the first D2D control channel to the counterpart terminal by applying the updated TA, but in the case of applying the updated TA, not to apply the information on the TA value included in the first D2D control channel.
1. A method for transmitting a signal via a Device-to-Device (D2D) link by a first User Equipment (UE) in a wireless communication system, the method comprising:
setting an information related to a first timing advance (TA) value obtained based on a first TA command received from a Base Station (BS);
transmitting, to a second UE, the information related to the first TA value via a first D2D control channel; and
transmitting, to the second UE, a first D2D data channel related to the first D2D control channel by applying the first TA value to the first D2D data channel;
setting an information related to a second TA value updated based on the first TA value and a second TA command received from the BS;
transmitting, to the second UE, the information related to the second TA value via a second D2D control channel; and
transmitting, to the second UE, a second D2D data channel related to the second D2D control channel by applying the second TA value to the second D2D data channel,
wherein the first D2D control channel and the second D2D control channel carry a control information for a D2D communication, and
wherein the first D2D control channel and the second D2D control channel are transmitted without applying the first TA value and the second TA value.
2. The method according to claim 1 , wherein an uplink signal for the BS is transmitted by applying the updated second TA value.
3. The method according to claim 1 , wherein the first D2D data channel is transmitted based on the first TA value until the second D2D control channel is transmitted.
4. A User Equipment (UE) for conducting communication via a Device-to-Device (D2D) link in a wireless communication system, the UE comprising:
a transceiver configured to transmit and receive signals to and from another UE or a Base Station (BS); and
a processor configured to process the signals,
wherein the processor is further configured to:
set an information related to a first timing advance (TA) value obtained based on a first TA command received from the BS,
control the transceiver to transmit the information related to the first TA value via a first D2D control channel,
control the transceiver to transmit a first D2D data channel related to the first D2D control channel by applying the first TA value to the first D2D data channel,
set an information related to a second TA value updated based on the first TA value and a second TA command received from the BS,
control the transceiver to transmit the information related to the second TA value via a second D2D control channel, and
control the transceiver to transmit a second D2D data channel related to the second D2D control channel by applying the second TA value to the second D2D data channel,
wherein the first D2D control channel and the second D2D control channel carry a control information for a D2D communication, and
wherein the first D2D control channel and the second D2D control channel are transmitted without applying the first TA value and the second TA value.
5. The UE according to claim 4 , wherein an uplink signal for the BS is transmitted by applying the updated second TA value.
6. The UE according to claim 4 , wherein the first D2D data channel is transmitted based on the first TA value until the second D2D control channel is transmitted.