USER EQUIPMENT, COMMUNICATION SYSTEM, AND BACKOFF CONTROL METHOD

摘要

This user equipment, which is capable of wireless device-to-device communication, is provided with the following: a resource-state detection unit that detects the state of each resource in a set of resources that can be used for device-to-device communication; a backoff control unit that, if the states detected by the resource-state detection unit satisfy a predetermined condition, puts the user equipment in a backoff state in which said user equipment does not transmit a discovery signal for a prescribed length of time; and a discovery-signal transmission unit that, if the user equipment is not in the aforementioned backup state, selects a resource from the abovementioned set of resources and uses the selected resource to transmit a discovery signal.