光学学报, 2018, 38 (7): 0711002, 网络出版: 2018-09-05
基于Nelder-Mead单纯形法的逆合成孔径激光雷达联合补偿成像算法 下载: 836次
Jointly Compensated Imaging Algorithm of Inverse Synthetic Aperture Lidar Based on Nelder-Mead Simplex Method
成像系统 高分辨率成像 Nelder-Mead单纯形法 逆合成孔径激光雷达 运动补偿 imaging systems high-resolution imaging Nelder-Mead simplex method inverse synthetic aperture lidar motion compensation
摘要
逆合成孔径激光雷达(ISAL)的调制信号具有高频率、大带宽的特性,使传统逆合成孔径雷达的“一步一停”模型不再适用。通过建立精确的ISAL成像模型,分析了ISAL成像过程中存在的平动误差、转动误差和模型误差。针对传统ISAL采用平动、转动分离补偿时,由于平动误差补偿存在残余误差而影响转动误差补偿的问题,因此提出基于Nelder-Mead单纯形法和拟牛顿法的联合补偿成像算法。该算法首先采用Nelder-Mead单纯形法对目标运动参数进行优化迭代搜索,将得到的优化解作为运动补偿项对三类误差进行全局补偿,然后利用拟牛顿法补偿残余误差。仿真实验结果表明,与传统分离补偿算法相比,本文算法可以精确估计目标的运动参数,获得聚焦良好的高分辨率ISAL二维图像。
Abstract
The modulation signal of inverse synthetic aperture lidar(ISAL) has the characteristics of high frequency and wide bandwidth, making traditional “stop and go” model of inverse synthetic aperture radar unavailable. By establishing accurate imaging model for ISAL, translational error, rotational error, and model error existed in ISAL image formation process are analyzed. When applying translational compensation and rotational compensation separately to traditional ISAL, the residual error existed in translational motion compensation influences the precision of subsequent rotational motion compensation. Jointly compensated imaging algorithm based on the Nelder-Mead simplex method and the quasi-Newton method is proposed. The proposed algorithm iteratively searches for motion parameters of the target based on the Nelder-Mead simplex method, the obtained optimal solution is used as the motion compensation term to eliminate three kinds of errors globally. Then the quasi-Newton method is applied for removing the residual error. Simulation results show that compared with the traditional separate compensation algorithm, the proposed algorithm can estimate motion parameters of target accurately and obtain a better quality of ISAL image.
刘盛捷, 付翰初, 魏凯, 张雨东. 基于Nelder-Mead单纯形法的逆合成孔径激光雷达联合补偿成像算法[J]. 光学学报, 2018, 38(7): 0711002. Shengjie Liu, Hanchu Fu, Kai Wei, Yudong Zhang. Jointly Compensated Imaging Algorithm of Inverse Synthetic Aperture Lidar Based on Nelder-Mead Simplex Method[J]. Acta Optica Sinica, 2018, 38(7): 0711002.