Method for transmitting and receiving control information for device-to-device (D2D) communication in wireless communication system and apparatus therefor
The present invention relates to a method and an apparatus for receiving control information of a terminal for device-to-device (D2D) ProSe in a wireless communication system. Specifically, the method comprises the steps of: receiving information on radio resources which are semi-statically configured for device-to-device proximity service (D2D ProSe); and receiving downlink control information (DCI) indicating whether or not D2D ProSe is activated on a specific radio resource of the radio resources, wherein the downlink control information is available only in a search procedure in which a resource for transmitting a terminal-specific search signal is allocated.
1. A method of receiving control information, which is received by a user equipment (UE) for a device-to-device (D2D) proximity service (ProSe) in a wireless communication system, the method comprising:
receiving information on radio resources semi-statically configured for the D2D ProSe; and
receiving a downlink control information (DCI) for indicating whether to activate the D2D ProSe on a specific radio resource among the radio resources,
wherein the DCI is valid in a discovery procedure to which a resource for UE-specifically transmitting a discovery signal is allocated,
wherein whether to activate the D2D ProSe is indicated using a resource block assignment field of a DCI format used for determining whether to activate semi-persistent scheduling, and
wherein a size of the resource block assignment field is determined according to a system bandwidth.
2. The method of claim 1 , wherein a length of a DCI format associated with the downlink control information corresponds to a length equal to or less than a predetermined length.
3. The method of claim 1 , wherein a length of a DCI format associated with the downlink control information is determined according to a bandwidth configured for the D2D ProSe.
4. The method of claim 1 , wherein the specific radio resource is indicated by an index of a D2D resource unit using the resource block assignment field.
5. The method of claim 1 , wherein the resource block assignment field is configured by first bits and second bits,
wherein the first bits are used for indicating an index of a D2D resource unit, and
wherein the second bits are used for indicating a D2D discovery subframe.
6. The method of claim 1 , wherein either a procedure of transmitting and receiving a D2D discovery signal or a procedure of transmitting and receiving a D2D communication signal is determined according to a position of the specific radio resource.
7. The method of claim 1 , wherein whether to activate the D2D ProSe is indicated by redefining a specific field among fields of the DCI format used for determining whether to activate the semi-persistent scheduling.
8. A user equipment (UE) for receiving control information for a device-to-device (D2D) proximity service (ProSe) in a wireless communication system, the UE comprising:
a transceiver; and
a processor configured to:
control the transceiver to receive information on radio resources semi-statically configured for the D2D ProSe, and
control the transceiver to receive a downlink control information (DCI) for indicating whether to activate the D2D ProSe on a specific radio resource among the radio resources,
wherein the DCI is valid in a discovery procedure to which a resource for UE-specifically transmitting a discovery signal is allocated,
wherein whether to activate the D2D ProSe is indicated using a resource block assignment field of a DCI format used for determining whether to activate semi-persistent scheduling, and
wherein a size of the resource block assignment field is determined according to a system bandwidth.