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The spectrum of radar signal will be modulated by moving target or vibration and turning part of the target,
this is called micro-Doppler effect. It is a new way of using micro-Doppler effect to realize the feature extraction and
target recognition. Because the complex vibration target has more complicated frequency component than the single
frequency target, so it is very useful to do the research of simulation and experiment of laser micro-Doppler effect for
detecting complex vibration. In this paper, the research on simulation and experiment of laser micro-Doppler effect for
detecting complex vibration of moving target was developed based on the simulation research of micro-Doppler effect in
lidar. Firstly, the geometry of complex vibrating target detection in radar was established. Secondly, the simulation and
experiment signal sources were compared and also the returned signals in radar of the simulation and experiment were
compared, the compared results showed that the two complex signal sources were very similar, and the frequency
change trend of returned signals in radar was the same. Thirdly, joint time-frequency analysis method of the reassigned
smoothed pseudo Wigner-Ville distribution (RSPWVD) was introduced to analyze the signals. The results showed that
in RSPWVD, the waveform of the vibration target, the target vibration period, the Doppler frequency shift and the
target’s speed can be got. The simulation results and the experiment results got by the RSPWVD had the basically same
frequency characteristics. So the RSPWVD can reflect very well the micro-Doppler characteristics of moving target’s
complex vibration. In conclusion it proved the validity of the simulated model, also it proved that using this
time-frequency method to analyze the micro-Doppler signal of complex vibration was correct. And it laid the foundation
of further using lidar to realize the classification and identification of target.
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