ENTRANCE AND EXIT MANAGEMENT SYSTEM PROVIDED WITH ENERGY-SAVING CIRCUIT AND PORTABLE TRANSMITTER-RECEIVER PROVIDED WITH THE ENERGY-SAVING CIRCUIT

摘要

PROBLEM TO BE SOLVED: To extend a service life of a battery that is a power supply of the portable transmitter-receiver by de-energizing the power supply of the portable transmitter-receiver when a possessor of the portable transmitter-receiver moves within a usually decided space and energizing the power supply of the portable transmitter-receiver only when the possessor exits from a designated gateway. ;SOLUTION: The portable transmitter-receiver C comprises two kinds of tag antennas, a noise cut filter circuit and a flip-flop circuit that selects ON/OFF of a power supply. When the portable transmitter-receiver C is going to exit from a gateway, a power supply of the portable transmitter-receiver C is turned on by a radio wave from a transmitter A installed at the gateway 51, the portable transmitter-receiver C transmits a radio wave to inform a receiver D of a position of the portable transmitter-receiver C. Once the portable transmitter-receiver C is about to enter the gateway 51, the power supply of the portable transmitter-receiver C is turned off by a radio wave from other transmitter B installed at the gateway 51.;COPYRIGHT: (C)2000,JPO