运动目标的全极化一维成像方法研究  

Fully Polarized One-Dimensional Imaging for Moving Target

作　　者：李棉全[1] 马梁[1] 李永祯[1] 戴幻尧[1] 王雪松[1] 

机构地区：[1]国防科技大学电子科学与工程学院,长沙410073

出　　处：《宇航学报》2011年第5期1136-1142,共7页Journal of Astronautics

基　　金：国家自然科学基金重点项目(60736006);国家自然科学基金青年科学基金项目(60802078)

摘　　要：提出了一种新的运动目标全极化一维成像方法,该方法利用解线性调频处理的小场景回波成像特性,使用小于发射脉冲宽度的时间延迟来实现不同极化通道之间的隔离,既能克服瞬时极化测量体制受发射波形特性限制的缺点,又能抑制传统分时极化测量体制长时间间隔导致的目标极化特性去相关效应。建立了运动目标的回波模型,分析了各相位因子的性质,针对不同的相位因子特性提出了相应的补偿方法:首先利用目标互易性原理对不同极化通道之间的相位差进行补偿,然后根据最小熵值准则实现对时延一次项和高次项精确补偿。仿真结果表明本文方法的有效性。In order to solve the probelem of decorrelation of target polarization characteristic in time division polarization measurement and the waveform limit in instantaneous polarization radar,a new fully polarized one-dimension imaging method for moving target is proposed based on dechirping.One trait of dechirping is the imaging of small scene.A delayed and smaller than the pulse width between two orthogonal polarized signals is used to get the isolation between different polarized channels.The smaller delay also can eliminate the decorrelation of target polarization characteristic induced by traditional long time division.An echo model for moving target is presented,and the theoretic model of phase signature is derived.According to different factors influencing the echo phase,a new compensation method is proposed.First,the inconsistent phase between different polarized channels is compensated by using the principle of reciprocity of target.Then,the phase is accurately compensated based on the entropy minimization principle.Numerical simulation results illustrate the validity of proposed method.

关 键 词：运动目标 全极化一维距离像 最小熵值准则 解线性调频 

分 类 号：TN95[电子电信—信号与信息处理]