对反射层析激光雷达近场小系统成像进行了理论分析与模拟验证,当目标处于瑞利索末菲衍射区域,到达目标的波前属于球面波衍射。根据奈奎斯特定律对球面波反射层析图像重建所需角度采样数,单投影采样点数约束条件进行了推导。引入了折线的方法,用于避免平方开方的距离运算,缩短图像重建时间。数值模拟表明此方法可以在降低计算量的前提下实现图像重建,随着探测距离的拉长,折线重建图像与参考图像相似度越来越高。

Theoretical analysis and simulation were made for near-field small system imaging of reflective tomography laser radar. In the Rayleigh-Sommerfeld diffraction domain,wavefront of the target belongs to spherical wave diffraction. According to Nyquist criterion,the constraints including the number of sampling angles and the number of sampling points in each projection for spherical wave reflective tomography were obtained. Broken lines method was introduced to avoid square and extraction operation and shorten imaging time. The simulation results show that double broken lines method was effective in solving the computational complexity problem in image reconstructed. Also with the increasing distance between the detector and the target,images reconstructed by the double broken lines method are close to the reference image.