| 摘要 |
PROBLEM TO BE SOLVED: To make power consumption zero during its standby by extracting with its surface acoustic wave device a specific pattern included in a reception signal received with a reception antenna to store the output voltage of this surface acoustic wave device in its storage circuit, and by switching on a switching circuit when the output voltage of the storage circuit exceeds a fixed value. SOLUTION: In a radio switching device 1, when a transmission signal is received by an antenna 11, applying it to the input pattern terminal of an SAW correlator 12, it is processed as a surface acoustic wave to transfer to a storage circuit 16 an output signal 14 of the SAW corrector 12 whose waveform has correlation peaks at every fixed period of a carrier. The storage circuit 16 takes in itself only the power component of these correlation peaks to charge its output capacitor. Then, when the output voltage of the storage circuit 16 exceeds a fixed value and the output capacitor is discharged by a threshold discharger 18, a relay SW (SW/ON in the case of this discharging) R2 is switched on to feed the voltage of a battery 20 to an application circuit 21. Therefore, the consumption power of the battery 20 in the case of the standby of the radio switching device 1 can be made zero. |
