| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the deterioration of cross range resolution of radar equipment by preventing the fluctuation of a reference-point frequency to partitioned frequency spectra for Doppler tracking by detecting the reference-point frequency and outputting the detected frequency as a tracking point for the calculation of a phase correcting amount. SOLUTION: A partitioned frequency analyzing circuit 15 analyzes the frequency of received signals at a certain range pin of the range-corrected received signals D at every small section in the direction of time and a data segmenting circuit 19 segments the area data of each amplitude value exceeding a set threshold 20. A front-edge frequency detecting circuit 21 detects front-edge frequency in a segmented area as a reference-point frequency f<k> and outputs the detected reference-point frequency to a smoothing circuit 17. The circuit 17 smoothes the locus of the reference-point frequency in the direction of time and a phase correcting amount calculating circuit 18 calculates the phase correcting amount ph used for phase correction from the smoothed locus. Therefore, a stable reference-point frequency f<k> can be obtained by setting the threshold to a value larger than the rising point, because the variation of the rising waveform is small even when the maximum amplitude value fluctuates.</p> |
