User equipment, feedback control method, and retransmission control method

Abstract

User equipment to be used as receiving user equipment in a mobile communication system supporting D2D communication, the user equipment includes a feedback unit that receives a D2D signal from transmitting user equipment, and that transmits, to the transmitting user equipment, a feedback signal with respect to the D2D signal by using a predetermined resource; and a receiver that receives a retransmission D2D signal transmitted from the transmitting user equipment based on the feedback signal.

1 . A user equipment to be used as a receiving user equipment in a mobile communication system supporting Device-to-Device (D2D) communication, the user equipment comprising:
 a feedback unit that receives a D2D signal from a transmitting user equipment, and that transmits, to the transmitting user equipment, a feedback signal with respect to the D2D signal by using a predetermined resource; and   a receiver that receives a retransmission D2D signal transmitted from the transmitting user equipment based on the feedback signal.   
     
     
         2 . The user equipment according to  claim 1 , wherein the feedback unit determines the predetermined resource based on, resource information explicitly or implicitly reported from the transmitting user equipment. 
     
     
         3 . The user equipment according to  claim 1 , wherein the feedback unit determines the predetermined resource based on scheduling control information corresponding to the D2D signal, the scheduling control information being received from the transmitting user equipment. 
     
     
         4 . The user equipment according to  claim 1 , wherein the feedback unit uses, as the predetermined resource, a resource in a Scheduling Assignment (SA) resource pool, or a resource in a resource pool for D2D data transmission. 
     
     
         5 . The user equipment according to  claim 1 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted. 
     
     
         6 . A user equipment to be used as a transmitting user equipment in a mobile communication system supporting Device-to-Device (D2D) communication, the user equipment comprising:
 a receiver that receives, from a receiving user equipment, a feedback signal with respect to a D2D signal transmitted to the receiving user equipment; and   a transmitter that transmits, to the receiving user equipment, a retransmission D2D signal with respect to the D2D signal, based on the feedback signal.   
     
     
         7 . The user equipment according to  claim 6 , further comprising:
 a control information transmitter that transmits, to the receiving user equipment, scheduling control information including transmission resource information of the D2D signal,   wherein the scheduling control information includes resource information to be used for determining a resource for transmitting the feedback signal in the receiving user equipment.   
     
     
         8 . The user equipment according to  claim 7 , wherein the control information transmitter transmits, to the receiving user equipment, the scheduling control information including information indicating the D2D signal to be retransmitted, prior to the retransmission D2D signal being transmitted. 
     
     
         9 . A feedback control method to be executed by a user equipment that is used as a receiving user equipment in a mobile communication system supporting Device-to-Device (D2D) communication, the feedback method comprising:
 a feedback step of receiving a D2D signal from a transmitting user equipment, and transmitting, to the transmitting user equipment, a feedback signal with respect to the D2D signal by using a predetermined resource; and   a reception step of receiving a retransmission D2D signal transmitted from the transmitting user equipment, based on the feedback signal.   
     
     
         10 . A retransmission control method to be executed by a user equipment that is used as a transmitting user equipment in a mobile communication system supporting Device-to-Device (D2D) communication, the retransmission control method comprising:
 a reception step of receiving, from a receiving user equipment, a feedback signal with respect to a D2D signal transmitted to the receiving user equipment; and   a transmission step of transmitting, to the receiving user equipment, a retransmission D2D signal with respect to the D2D signal, based on the feedback signal.   
     
     
         11 . The user equipment according to  claim 2 , wherein the feedback unit determines the predetermined resource based on scheduling control information corresponding to the D2D signal, the scheduling control information being received from the transmitting user equipment. 
     
     
         12 . The user equipment according to  claim 2 , wherein the feedback unit uses, as the predetermined resource, a resource in an SA resource pool, or a resource in a resource pool for D2D data transmission. 
     
     
         13 . The user equipment according to  claim 3 , wherein the feedback unit uses, as the predetermined resource, a resource in an SA resource pool, or a resource in a resource pool for D2D data transmission. 
     
     
         14 . The user equipment according to  claim 11 , wherein the feedback unit uses, as the predetermined resource, a resource in an SA resource pool, or a resource in a resource pool for D2D data transmission. 
     
     
         15 . The user equipment according to  claim 2 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted. 
     
     
         16 . The user equipment according to  claim 3 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted. 
     
     
         17 . The user equipment according to  claim 4 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted. 
     
     
         18 . The user equipment according to  claim 11 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted. 
     
     
         19 . The user equipment according to  claim 12 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted. 
     
     
         20 . The user equipment according to  claim 13 , wherein the receiver receives the scheduling control information for reporting a transmission resource of a retransmission D2D signal, prior to receiving the retransmission D2D signal, and the scheduling control information includes information indicating the D2D signal to be retransmitted.