REMOTE SECURITY EQUIPMENT UTILIZED PIEZOELECTRIC CABLE

摘要

PURPOSE: A remote security device is provided to accurately detect external intrusion. CONSTITUTION: An analog circuit part(20) is composed of an OP amp, a comparator, a monostable multivibrator, and a sensor module. The OP amp is connected to a piezoelectric cable(10) and amplifies an electric signal which is generated according to pressure applied from the outside of the piezoelectric cable. The comparator compares the amplified electric signal with a threshold voltage. The monostable multivibrator applies the output signal of the comparator to an input terminal and generates an edge waveform output signal. A sensor module generates an output signal by removing and amplifying noise from the electric signal. An information processor(50) stores inputted data and determines the property of external pressure by comparing a digital output signal with the delayed edge waveform digital output signal of the monostable multivibrator according to an inputted command.