| 摘要 |
PROBLEM TO BE SOLVED: To accurately perform a grouping of a peak for each target when there is a plurality of reflection points of a target.SOLUTION: A frequency spectrum (thereafter referred to as a first frequency spectrum) of a beat signal is calculated by subjecting the beat signal to FFT by use of the beat signal of a frequency increase segment or for T/2 of a frequency reduction segment. Further, out of the beat signal of the frequency increase segment or for the T/2 of the frequency reduction segment, only a part of a predetermined segment T' smaller than the T/2 is extracted, the extracted beat signal is used to be subjected to the FFT, and a second frequency spectrum is calculated. Respective peaks of the first frequency spectrum and the second frequency spectrum are detected and compared. Then, as to each peak of the second frequency spectrum, a grouping of a peak group of the first frequency spectrum included in the peak as one group is performed. |
