Patent ID: 9705644
Date: 2017-07-11
CPC Classifications: H04L,H04W

Claim:
1. A method for performing a device-to-device (D2D) communication by a user equipment (UE) in a wireless communication system, the method comprising: receiving, by the UE from an evolved Node B (eNB), a hybrid automatic repeat and request (HARQ) process configuration for configuring a specific downlink HARQ process among several downlink HARQ processes as a D2D HARQ process; and transmitting, by the UE, an uplink acknowledgement/negative acknowledgement (ACK/NACK) for the D2D communication by using a soft buffer for the D2D HARQ process according to the D2D HARQ process, wherein the soft buffer for the D2D HARQ process is allocated based on a soft buffer for the specific downlink HARQ process indicated by the HARQ process configuration, and wherein a size of the soft buffer for the D2D HARQ process is configured to be larger than a size of a soft buffer for an eNB-to-UE HARQ process.