Patent ID: 9750055
Date: 2017-08-29
CPC Classifications: H04L,H04W

Claim:
1. A user terminal that supports cellular communication and device-to-device (D2D) proximity service, comprising: a receiver configured to receive first information from a base station, the first information indicating a D2D resource pool reserved from among uplink radio resources of the cellular communication, wherein the uplink radio resources include physical random access channel (PRACH) resources used for PRACH transmission in the cellular communication; the receiver further configured to receive second information from the base station, the second information designating the PRACH resources; a controller configured to select radio resources from among the D2D resource pool, the radio resources used for D2D transmission, wherein the controller selects the radio resources while avoiding selection of the PRACH resources; and a transmitter configured to transmit D2D signals to other user terminals using the selected radio resources, the D2D signals including a D2D discovery signal used to discover a proximity user terminal.