US Patent 10175346 Laser radar apparatus and wind velocity observation method

A wind velocity searching unit 30 is configured so as to, when a spectrum signal calculated by a spectrum calculating unit 22 is one in a range bin having a signal strength less than a first threshold Th1, determine a search center IF of the search scope for a Doppler frequency corresponding to a wind velocity in the range bin by using a wind velocity model selected by a wind velocity model selecting unit 29, and search for the wind velocity in the range bin from the spectrum signal within the search scope whose search center IF is determined thereby. As a result, the probability that the peak of noise is detected erroneously as the peak of the spectrum signal is reduced.