基于窄带的自旋目标成像算法研究

A Study on Spinning Targets Imaging Algorithm Based on Narrow-band

随着空天活动的日益频繁,对空天微动目标监视鉴别变得越来越重要。文中研究了一种基于压缩感知和反投影技术的窄带逆合成孔径雷达成像方法,该方法主要考虑了在实际应用中雷达资源有限,而窄带信号也会受到干扰或缺失导致难以对其成像。首先,运动补偿后通过压缩感知算法对稀疏窄带信号进行恢复;其次,通过高性能Gabor时频变换对恢复的窄带信号进行时频分析,得到目标信号时频分布图;然后,通过组相关方法稳健地估计出目标的旋转周期;最后,利用反投影算法实现对目标的有效成像、仿真数据验证了所提方法的有效性和可行性。

With the increasing frequency of air-space activities,it is becoming more and more important to monitor and identify aerospace micro-motion targets.In this paper,a narrow-band ISAR imaging method based on compressive sensing and back-projection is studied.This method mainly considers two factors which will influence the imaging of micro-motion targets in practical applications:limited radar resources and disturbed or absent narrow-band signal.First,compressive sensing algorithm is employed to reconstruct the sparse narrow-band echo after motion compensation.Second,time-frequency analysis is performed on the narrow-band echo via high-performance Gabor time-frequency transform to obtain the time-frequency distribution map of the target signal.Third,rotation period of target is estimated robustly through group correlation method.Finally,back-projection algorithm is adopted to realize imaging of the target effectively.The effectiveness and feasibility of the proposed method is verified by simulation data.