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合成孔径成像激光雷达是一种新的主动式有源的成像系统,可以获得比合成孔径雷达更高的分辨率,和更接近光学图片的效果。首先,在理想条件下分析了调频连续波的信号模型,推导出在连续波系统聚束模式下一种适用于机载合成孔径成像激光雷达系统的频率变标算法。然后,使用傅里叶变换法对符合von Karman谱的随机相位屏模拟大气湍流,并分析了Fried参量和合成孔径长度之间的关系。最后,仿真说明真空中采用方位预处理可以消除图像重影,并且补偿多普勒频移项可以消除8.6～9.3dB的能量损失和使图像散焦的现象。而在有大气影响时,合成孔径长度的选择小于Fried参量时,图像方位向可以良好聚焦。
Synthetic Aperture Imaging Lidar is a new active active imaging system that offers higher resolution than synthetic aperture radar and closer to optical imagery. Firstly, the signal model of FM continuous wave is analyzed under the ideal conditions, and a frequency scaling algorithm suitable for airborne synthetic aperture imaging lidar system is deduced under the condition of continuous beam system. Then, a random phase plate complying with the von Karman spectrum was used to simulate the atmospheric turbulence using the Fourier transform method, and the relationship between Fried parameters and the length of the synthetic aperture was analyzed. Finally, the simulation shows that the azimuth preprocessing in the vacuum can eliminate the image ghost, and compensating the Doppler shift term can eliminate the energy loss of 8.6 ~ 9.3dB and defocus the image. However, when there is atmospheric influence, the choice of the synthetic aperture length is less than the Fried parameter, the image orientation can be well focused.