基于隐函数导数法的双基弧形阵列SAR二维频谱及成像算法  

A Two-Dimensional Spectrum and Imaging Algorithm for Arc Array Bistatic SAR Using Derivatives of An Implicit Function

作　　者：黄平平[1,2] 李凯 徐伟 谭维贤 高志奇[1,2] HUANG Pingping;LI Kai;XU Wei;TAN Weixian;GAO Zhiqi(College of Information Engineering,Inner Mongolia University of Technology,Hohhot,Inner Mongolia 010051,China;Inner Mongolia Key Laboratory of Radar Technology and Application,Hohhot,Inner Mongolia 010051,China)

机构地区：[1]内蒙古工业大学信息工程学院,内蒙古呼和浩特010051 [2]内蒙古自治区雷达技术与应用重点实验室,内蒙古呼和浩特010051

出　　处：《信号处理》2021年第4期496-506,共11页Journal of Signal Processing

基　　金：国家自然科学基金(61631011,61761037,61971246,62071258);内蒙古自治区自然科学基金(2020ZD18)。

摘　　要：双基弧形阵列合成孔径雷达(Arc array Bistatic synthetic aperture radar, AA-BiSAR)是一种新型全方位观测阵列成像雷达系统,其成像范围大、数据收集速率快且不易被侦测。然而,在弧形阵列SAR模式中,双基弧形阵列SAR天线特殊的圆弧型结构,回波信号的二维频谱难以用传统的驻定相位原理进行解析。针对以上问题,本文引入隐函数的思想,将驻定相位点视为多普勒频率的一个隐函数,在对隐函数方程进行求导后运用代数运算求解出该驻相点,从而可以直接利用驻定相位原理来推导出双基弧形阵列SAR的二维频谱,并基于此频谱研究了一种适用于双基弧形阵列SAR的高分辨率成像处理方法,最后点目标的仿真结果验证了结论的正确性与该成像方法的有效性。Arc array Bistatic synthetic aperture radar(AA-BiSAR) is a novel imaging system for full azimuth observation, which can obtain high data acquisition efficiency and reduce vulnerability of arc-array monostatic SAR. Due to the special arc antenna configuration of AA-BiSAR, it is difficult to have access to the two-dimensional frequency spectrum for AA-BiSAR via the principle of stationary phase(POSP). In view of the above problems, the method of implicit function is introduced into AA-BiSAR in this paper. The stationary phase can be considered as an implicit function of the Doppler frequency, and after deriving the implicit function equation, the stationary point can be solved by algebraic operation. On that account, the 2-D spectrum can be directly obtained by using the principle of stationary phase. On the basis of the previously obtained spectrum, an imaging algorithm based on the derived spectrum is developed for AA-BiSAR. The numerical simulation results of point target demonstrate the validity and effectiveness of the approach.

关 键 词：双基弧形阵列合成孔径雷达 全方位观测 成像方法 隐函数导数法 二维频域 

分 类 号：TN958[电子电信—信号与信息处理]