一种基于去斜的高速目标ISAR成像新方法  

Novel Algorithm of High-Speed Target ISAR Imaging Based on Stretch Method

作　　者：罗文茂[1] 崔应留 

机构地区：[1]南京信息职业技术学院通信学院,江苏南京210023 [2]南京审计学院工学院,江苏南京211815

出　　处：《系统仿真学报》2016年第4期851-858,866,共9页Journal of System Simulation

基　　金：国家自然科学基金(61170105);南京信息职业技术学院‘青蓝工程’

摘　　要：目标高速运动会使回波脉冲压缩结果畸变,导致ISAR的传统R-D成像算法失效。据此,提出了一种基于调频傅里叶变换的高速目标成像算法。该算法对去斜差频信号进行调频傅里叶变换,得到每个回波的距离和速度估计,对成像积累时间内的速度估计值求平均,得到目标的精确速度估计,以此构造补偿信号消除脉内和脉间走动,从而得到正确的成像结果。由于调频傅里叶变换在脉冲重复周期内完成,所以该算法能满足实时性要求。该算法能同时进行目标运动参数估计和成像,且算法结构简单,抗噪能力强,易于工程实现。The pulse compression result will be distorted while the target moves very fast and it cannot get right ISAR images. A novel algorithm based on chirp-Fourier transform was proposed to solve this problem. In the scheme, every echo＇s differential frequency signal of stretch processing was calculated by chirp-Fourier transform to estimate the target＇s location and speed, and the target＇s precious speed could be averaged by the estimations during the whole dwell time. Then the penalty function could be constructed to eliminate the intra and inter-pulse motion, and it could get right ISAR images. Because the chirp-Fourier transform was completed during the pulse repetition period, the algorithm could meet the real-time requirement. Further more the algorithm could simultaneously accomplish moving parameters estimation and imaging. The algorithm has the advantages of simple structure and strong anti-noise ability, so it is easy to implement in Engineering.

关 键 词：ISAR成像 去斜处理 线性调频信号 调频傅里叶变换 运动参数估计 

分 类 号：TN957.52[电子电信—信号与信息处理]