| 摘要 |
PURPOSE:To grasp accurately numbers of empty cars, by calling the empty cars from a base station with an aural signal and encoding response signals in the empty cars and transmitting response signals time-differentially from the empty cars. CONSTITUTION:A base station calls empty cars with an aural signal, and a polling signal is transmitted when a press button is turned off at the end of calling. When a mobile station receives the polling signal, a timer is operated by the fall of this signal. Operating times t1-t7 of timers are different in mobile stations. When a response button is depressed in the mobile station to respond to the call signal, a signal obtained by encoding the car number of the mobile station is transmitted to the base station just when a corresponding time-out of operating times t1-t7 of timers is elapsed. |
