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When detecting moving targets via photon counting Lidar, the target information contained in the echo photon statistical histogram is distorted, because the target position in a cumulative time changes. To solve the above distortion, this work proposed a method of acquiring moving target structural characteristics from the photon echo statistical histogram via waveform processing. Firstly, the probability distribution model of photon detection echo corresponding to a moving target was established. Then, the mathematical expressions of the laser radar cross section (LRCS) and depth structure corresponding to a moving target were derived by utilizing the photon waveform correction and waveform fitting filtering. Finally, the structural characteristics of a multi-layer moving target with a speed of 20m/s at 10km were obtained. Under the condition of SNR (signal-to-noise ratio) being 1.48, to detect a multi-layer moving target composed of two sub-targets with 0.5×1m, between which the distance was 0.5m, when the detection time was 0.01s (i.e., the cumulative number was 300), the consequential LRCS was 1.009m², and the ratio of LRCS within the moving target was 0.967:1. Meanwhile, the depth within the sub-targets was 0.493m, whose error was less than 0.7%. The proposed method in this work provided theoretical support for the acquisition of moving target detail information and the recognition of moving targets.
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