PURPOSE: To omit the ON/OFF operation of a radio wave during short time between paging signals from the paging signal subsequent to that one received by receiving the paging signal once by means of a first battery saving operation.
CONSTITUTION: Immediately after starting, whether or not a preamble signal PA is received is checked by turning on/off the power supply of a radio part 2. When the signal PA is received, the power supply is continuously turned on for a time period B3 and whether or not a synchronous code SC is received is checked. When the code SC is detected, a timer for time B4 is started and the receiving operation of a call signal following the code SC is actuated. When it is judged that the call signal is not transmitted, the power supply of the radio part 2 is continuously turned off for a time period of the residual time of the couting time B4. After the lapse of time B4, the power supply is continuously turned on for a time period B1 and whether or not the signal PA is detected is checked. When the signal PA is detected, the detection of the code SC is executed. When the code SC is not detected, the battery saving operation for a short time period B is actuated.