| 摘要 |
PURPOSE:To keep the communication through an idle communication channel by detecting the movement of a slave set to the outside of a communication zone, and setting the channel having been communicated therethrough and a control channel to the channel of a master set alternately. CONSTITUTION:When an outer-communication zone detection means detects the movement of a slave set to the outer-communication zone, the control channel and the communication channel are set alternately for a prescribed time to detect the presence of the signal from each channel by a signal detection means 2. When the signal detection means 2 detects a signal from the control channel, the communication is restarted via an idle communication channel. Furthermore, when a signal from the communication channel is detected, the communication is restarted through the communication channel. When the slave set returns in the communication zone, the master set detects a signal from the slave set through either channel to attain smooth communication. |
