| 摘要 |
<p>PURPOSE:To make it possible to perform accurate identification by providing an FM-CW radar device for receiving the reflected wave from a body to be detected and for outputting the beat signal, a high-speed Fourier transformation (FFT) circuit, a peak-power-spectrum detecting means and an obstacle detecting means. CONSTITUTION:When the transmitting signal which is modulated with the modulating signal having a specified waveform is transmitted, the echo from a body to be detected which is located at the forward position is received. The obtained received signal is mixed with a part of the transmitted signal, and the beat signal representing the relative speed of the body to be detected is obtained. The beat signal further undergoes FFT processing in an FFT circuit 38, and the spectrum of the beat signal is obtained. The signal is supplied into a peak- power-spectrum detecting means 46. Since a constant-value part is included in the modulating signal, the transmitted signals have the non-modulated parts, respectively. The difference frequency caused by a distance (r) does not appear in the non-modulated part, and the doppler component caused by the relative speed (v) appears. An obstacle detecting means 50 judges whether the body to be detected is the moving body or not based on the relative speed.</p> |
