| 摘要 |
PURPOSE:To reduce the power consumption of a mobile body by detecting a series of time information inserted into a message of a prescribed period at the mobile body side and inactivating the receiver of each mobile body till a prescribed time zone when the message received next at each mobile body is sent based on the information. CONSTITUTION:A computer 20 is provided with a frame number detection circuit 21, a designated frame number storage circuit 22 and a clock 23. A frame number detected from a demodulated output of a receiver 11 by the detection circuit 21 is a series of time information and the designated frame number stored in the storage circuit 22 corresponds to the transmission time zone of the designated message addressed to the mobile station. Then based on the detected frame number by the detection circuit 21 and the designated frame number from the storage circuit 22, the reception timing of the designated message is calculated and the clock 23 is set and the clock 23 controls the switching of a switch 14. Thus, the power consumption of the mobile body is reduced. |
