CAJ | 학술논문

当目标机动飞行时,常规的距离多普勒算法进行成像时会散焦甚至无法成像.为实现机动目标的快速高分辨成像,研究了一种基于压缩感知(CS)的机动目标高分辨成像方法.首先,在小角度条件下,将目标机动等效为匀加速转动,在分析机动目标方位向回波特征的基础上,构建了更加符合回波特征的匹配傅立叶字典;然后,依据不同散射点的旋转角加速度与旋转初速度的比值是相同的这一信息,将回波沿快时间积分后,变换为一列方位向信号,结合CS重构进行参数估计;最后,采取矩阵形式的重构算法快速获得ISAR图像.仿真和理论分析验证了本文方法的有效性.
당목표궤동비행시,상규적거리다보륵산법진행성상시회산초심지무법성상.위실현궤동목표적쾌속고분변성상,연구료일충기우압축감지(CS)적궤동목표고분변성상방법.수선,재소각도조건하,장목표궤동등효위균가속전동,재분석궤동목표방위향회파특정적기출상,구건료경가부합회파특정적필배부립협자전;연후,의거불동산사점적선전각가속도여선전초속도적비치시상동적저일신식,장회파연쾌시간적분후,변환위일렬방위향신호,결합CS중구진행삼수고계;최후,채취구진형식적중구산법쾌속획득ISAR도상.방진화이론분석험증료본문방법적유효성.
The imaging would be defocused or even not be imaged by the conventional range Doppler (RD) algorithm when a target carries on a maneuvering flight. For implementing the fast imaging with high resolution for a maneuvering target, an imagine method with high resolution for maneuvering target is studied, based on compressive sensing (CS) in this paper. In this scheme, at first, the target maneuvering can be equivalent to an uniformly accelerative rotation in the case of small angle, and the matching Fourier dictionary is constructed that is more in line with the echo features, after analyzing the echoes'characteristics in the azimuth of maneuvering target,and then, in accordance with the information that the ratios of the rotational angular acceleration to the rotational initial velocity are identical at various scattering points, the echoes are integrated over the fast time and converted to a column of azimuth-oriented signals, and the parameter estimation is carried by combining with the cs reconstruction, and finally, the ISAR image is fast obtained by adopting the reconstruction algorithm in matrix form. By simulation and theoretical analysis, this proposed method is proved to be of effectiveness.