Patent ID: 7724182

Claim:
A radar system which transmits a radar wave, receives a reflected wave that is the radar wave which has been reflected or scattered by an object, and detects the object by the reflected wave, said radar system comprising: a transmitter which transmits the radar wave via a transmission antenna; a receiver which receives the reflected wave via a receiving antenna; a delay line which has an end connected to an output port of said transmitter and an other end connected to an input port of said receiver, and which delays the radar wave by a predetermined delay amount; a detector which detects a waveform having a strength equal to or higher than a predetermined strength, from a signal provided from said receiver which obtains the signal from one of the reflected wave and the radar wave delayed by said delay line; and a judger which judges, when self-diagnosis is performed, whether the waveform detected by said detector is a waveform of the radar wave delayed by said delay line according to the predetermined delay amount, and when the waveform is not the waveform of the radar wave delayed by said delay line, determines that an abnormality occurs in said radar system, wherein said radar system employs a spread spectrum scheme using a pseudo noise code, and wherein a line length of said delay line is shorter than a line length of a maximum delay line by which the radar wave is delayed by a delay amount equivalent to one cycle of a code length of the pseudo noise code.