逆合成孔径激光雷达(ISAL)相比逆合成孔径雷达(ISAR), 其信号源具有更小的发散角, 同分辨下具有更小的合成孔径累积角度的优点, 从而获得关注。但是因为ISAL采用激光器为雷达信号源, 而且激光雷达与微波雷达调制原理不同, 导致在ISAR中主流的扩频方案如线性调频并不适用于真实的ISAL。为了获得高重复性的并且在极短时间内宽频的探测信号, 采用了光通信中广泛使用的最长序列相位调制。在说明了其远场回波信号模型和对应的成像算法之后, 指出了其与传统算法之间的区别。最后, 使用由多个散射中心点组成的成像目标, 进行了成像算法仿真和结果分析。仿真参数与成像结果表明: 该方法为一种可采用的实时ISAL调制方法。

The inverse synthetic aperture lidar(ISAL) have attracted increasing attention for its merits including smaller divergence angle of the signal source and smaller synthetic aperture under same cross-range resolution when compared with its inverse synthetic aperture radar (ISAR) counterpart. However, by using lidar instead of radar as the signal source, the most popular spread-spectrum techniques such as linear frequency modulation are not suitable for a practical ISAL. In order to obtain a highly repeatable and a broad frequency signal in a very short time, a maximum length sequence coded phase modulation method, which was a widespread method in optical communication, was adopted in this paper. The far-field signal model and the corresponding imaging algorithm were introduced in the first place. The main differences from traditional algorithms were addressed thereafter. Finally, a well-designed simulation target composed of several scattered center points was used to verify the validity of the proposed imaging algorithm. The results are analyzed with imaging parameters to prove the method introduced by this paper is adaptable for real-time ISAL.