US Patent No. 10,251,167


Patent No. 10,251,167
Issue Date April 02, 2019
Title D2d Signal Transmission Method And User Equipment
Inventorship Hakseong Kim, Seoul (KR)
Hanbyul Seo, Seoul (KR)
Assignee LG ELECTRONICS INC., Seoul (KR)

Claim of US Patent No. 10,251,167

1. A method for broadcasting a device-to-device (D2D) signal by a user equipment (UE) positioned outside a coverage of a base station (BS), the method comprising:transmitting a first message including a preamble sequence to a first D2D UE in a cluster, wherein an index of the preamble sequence is determined based on a resource used for transmission of the first message;
receiving a second message from the first D2D UE in the cluster as a response to the first message, wherein the second message contains scheduling information to broadcast a third message;
broadcasting the third message in the D2D signal to a plurality of D2D UEs in the cluster based on the scheduling information;
receiving a plurality of ACK/NACKs (acknowledgement/negative-acknowledgements) for the third message from the plurality of D2D UEs in the cluster; and
re-broadcasting the third message in a D2D signal to the plurality of D2D UEs in the cluster if a proportion of NACK among the plurality of ACK/NACKs is equal to or larger than a certain value.