As the laser signal of inverse synthetic aperture imaging LADAR (ISAIL) has high frequency, large bandwidth and short wavelength, conventional range-Doppler can not be used again. This paper analyzes the characteristic of echo signals, finishes time-frequency analysis for the signal after optical heterodyne processing with reassign smoothed pseudo WVD and Radon transform. The velocity of targets is estimated and the echo signal is compensated accurately, and the high resolution two dimensional imaging can be realized. The simulation shows that this method is effective, and the images achieved by the ISAIL system have higher quality than the microwave inverse synthetic radar system.%逆合成孔径成像激光雷达发射的激光信号具有极高载频、超大带宽和极短波长的特性,传统的距离-多普勒算法不再适用.在对回波信号特征进行分析的基础上,利用重排Wigner分布和Radon变换对光外差探测后的信号进行时频分析,估计出目标的径向速度,实现对回波信号的精确运动补偿.最后利用改进的距离-多普勒算法,完成对目标的超高分辨二维成像.仿真验证了成像算法的有效性,并通过与微波波段逆合成孔径雷达的比较,证明了逆合成孔径成像激光雷达可以实现对运动目标更快速、更高分辨的成像.
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