利用压缩感知的逆合成孔径激光雷达成像新方法

Novel imaging method using compressed sensing for the inverse synthetic aperture imaging ladar

受限于激光调制技术,在较长的积累时间内,逆合成孔径成像激光雷达发射脉冲之间的相干性难以保持,导致方位向散焦,影响成像效果.为此提出了一种在较短相干积累时间内,利用较少回波数据实现同等分辨率的瞬时成像算法.此算法利用压缩感知理论,将逆合成孔径成像激光雷达成像问题转换为利用正交基压缩感知重构稀疏信号的问题,通过优化求解的方式对目标像优化重建,且在低信噪比时通过构造权矩阵,提高算法对目标像的恢复性能.室内逆合成孔径成像激光雷达验证系统实测数据验证了算法的可行性和有效性.

Limited by the laser modulation technique, the coherence between transmitting pulses of the inverse synthetic aperture imaging ladar （ISAIL） can not be kept, which leads to the unfocused image in the azimuth direction. Here, an instantaneous imaging algorithm is proposed to achieve the high resolution with less echo data in a short coherence time. Based on the theory of compressed sensing, the ISAIL imaging is converted into a reconstruction issue using the orthogonal base. The reconstruction of the target is resolved by optimizing the function. Under the situation of a low SNR, the performance of the imaging algorithm is improved by constructing a weighted matrix. Experimental results using measured data of the indoor ISAIL system validate the feasibility and effectiveness of our method.