| 摘要 |
<p>PROBLEM TO BE SOLVED: To miniaturize a radar apparatus and to enhance its accuracy. SOLUTION: In a radar apparatus of an FM-CW system, a beat signal is frequency-converted by an FFT circuit 40. A signal processing circuit 44 first finds distribution of the signal level of the beat signal with reference to a frequency and to a measuring angle, by using the frequency component of the beat signal obtained in every period of every increase period and every decrease period. The signal level Lp and the frequency fp of the maximum point of a curved surface which expresses the distribution of every period as well as the central angleθm and the angle widthΔθa of an angle range are found as variables of data on the maximum point. In addition, data on maximum points in both periods are compared. The combination of the maximum points in which the difference between the variables is less than a reference value is found. On the basis of the data on the maximum points, the relative distance between a target and the radar apparatus and their relative speed as well as the position and the size of the target are found. As a result, the position and the size of the target can be found without narrowing the beam width of transmitting waves.</p> |
