A user equipment (UE) communication method, a device, and a communications system are provided. A first UE sends a notification message to a cellular network access device, wherein the notification message indicates that the first UE requests to be a beacon device. The first UE receives, from the cellular network access device, a message indicating that the first UE is the beacon device. The first UE sends detection signal, wherein the detection signal is for a second UE to detect the detection signal.