Patent ID: 6614384
Filing Date: 2003-09-02
Classification: G01S,G08B,H04B

Abstract:
A security system comprising:a transmitting impulse radio unit for transmitting an impulse radio signal including a series of impulses; a receiving impulse radio unit for receiving the impulse radio signal at and after a predetermined time and generating a first waveform which is a time domain representation of the received impulse radio signal that indicates an actual distortion of the transmitted impulse radio signal that was transmitted within a protection zone at and after the predetermined time; said receiving impulse radio unit for receiving the impulse radio signal at and after a subsequent time and generating a second waveform which is a time domain representation of the received impulse radio signal that indicates an actual distortion of the transmitted impulse radio signal that was transmitted within the protection zone at and after the subsequent time; and a processor for comparing the first waveform to the second waveform to determine whether there is a change between the first waveform and the second waveform caused by an intruder entering the protection zone.