| 摘要 |
<p>A modulation signal generation circuit (29) performs frequency modulation of a VCO (24) with a triangular wave for operation as an FM-CW radar. A signal processing circuit (30) gives a modulation signal for detection generated from the modulation signal generation circuit (29) to the VCO (24). A high-frequency signal subjected to frequency modulation in the VCO (24) is transmitted as a radio wave from a transmission antenna and is reflected on a target and the reflected radio wave is received at a reception antenna. The reception signal and the high-frequency signal are mixed by a mixer (26) to provide a beat signal and frequency shift corresponding to a voltage V1 is detected from the frequency of the beat signal. If the voltage V1 of the modulation signal for detection is switched, the frequency shift corresponding to different voltage V1 can be provided and the frequency modulation characteristic can be detected. <IMAGE> <IMAGE> <IMAGE></p> |
