| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a radar capable of finding the orientation of a target accurately even if the target, e.g. a preceding traveling vehicle, is located at the end of the scanning range of radar beam. SOLUTION: An FM modulated radar signal is radiated from a transmitting/ receiving antenna 27 while scanning the beam direction with a predetermined beam and a reflected signal from a target is mixed with a part of transmitting signal at a mixing section 25 to produce a beat signal 25a. An effective reflective cross-sectional area operating section 33 finds an effective reflective cross- sectional area, based on the receiving level under a state where the beam center impinges on the target, the antenna gain at the center of beam, and the detected distance to the target. When the target exists slightly on the outside of scanning range of the radar beam, an orientation operating section 32 the antenna gain from the receiving signal level if the effective reflective cross-sectional area of the target is known and finds the orientation of the target, based on the antenna gain thus determined and a previously registered angle-gain characteristics of radar beam.</p> |
