| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain highly accurate information on target from the searching results of target by FM-CW system. SOLUTION: A target 22 is searched by transmitting a search signal 40 for every constant angular interval while scanning through an antenna 23. The transmission angle of the search signal is shifted in the reciprocal search. The direction of the target 22 can be detected as accurately as at the time when the target is searched at a fine angular difference by combining the results of search obtained by repeating scanning a plurality of times while shifting the angle. Relative movement of the target 22 incident to a plurality of times of scanning is regarded as Doppler shift and the data are combined while taking account of frequency shift. Uncombinable data is handled as unnecessary reflected data and a position, where unnecessary reflected data concentrate, is judged as the shoulder of a road. The height of a stationary target is also judged from the variation state of reflection signal level at the time of approaching it.</p> |
