Phase modulated lidar imaging design and simulation

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 crossrange 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 farfield 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 imagingalgorithm. The results are analyzed with imaging parameters to prove the method introduced by this paper is adaptable for real-time ISAL.