公开(公告)号：EP2987361A4

公开(公告)日：2016-05-18

申请号：EP14795413

申请日：2014-05-10

申请人： HUAWEI TECH CO LTD

发明人： SARTORI PHILIPPE ,  DESAI VIPUL ,  AL-SHALASH MAZIN ,  SOONG ANTHONYC K ,  CALCEV GEORGE ,  CLASSON BRIAN

IPC分类号： H04W48/08 ,  H04W4/00

CPC分类号： H04W76/023 ,  H04W4/005 ,  H04W8/005 ,  H04W56/0015 ,  H04W56/002

摘要： Embodiments are provided herein for determining a synchronizing master for device-to-device (D2D) communication in a cellular network environment. In an embodiment, a user equipment (UE) receives a discovery signal comprising a timing reference, and determines a transmitter of the discovery signal. In accordance with the determination of the transmitter of the discovery signal, the UE performs one of synchronizing to the timing reference in the discovery signal and transmitting a second discovery signal. The UE performs the synchronizing to the timing reference if the transmitter of the discovery is a cellular network. Alternatively, the UE transmits the second discovery signal upon determining that the transmitter of the discovery signal is a second UE that is out of coverage of a cellular network.