雷达极化域调控超分辨的原理与方法  

Principle and approach to polarization modulation for radar super-resolution

作　　者：王罗胜斌 王雪松[1] 徐振海[1] Luoshengbin WANG;Xuesong WANG;Zhenhai XU(State Key Laboratory of Complea Electromagnetic Environment Effects on Electronics and Information System,National University of Defense Technology,Changsha 410037,China)

机构地区：[1]国防科技大学电子信息系统复杂电磁环境效应国家重点实验室,长沙410037

出　　处：《中国科学：信息科学》2023年第5期993-1007,共15页Scientia Sinica(Informationis)

基　　金：国家自然科学基金(批准号:61625108)资助项目。

摘　　要：分辨是雷达领域的经典问题,尽管经过几十年的发展,但“分不开、辨不清”的矛盾在雷达各类应用中日益凸显.在雷达分辨研究中,模糊函数理论占据绝对主流,同时尝试突破瑞利(Rayleigh)分辨极限的超分辨研究层出不穷,这些方法具有一定的超分辨效果,但因其前提假设而在工程应用中受限.传统分辨理论并未考虑电磁场的极化特性,利用极化技术可大幅提升雷达分辨能力,研究极化与分辨的关系具有重大理论价值.本文从模糊函数出发,重点分析目标幅度和相位对分辨效果的影响,得出“等幅反相”可使雷达突破分辨率极限,结合雷达收发极化调控技术,创新性提出极化域变焦理论,通过全极化域距离像阐释超分辨原理,并且针对实际雷达系统,提出极化域变焦多目标检测与分辨方法,实现多目标的正确判决和距离的有效估计.仿真结果表明,极化域变焦处理对交叉极化不敏感,在高信噪比条件下可将雷达分辨力提升约20倍.As a classical topic in the radar field,radar resolution theory has been developing for decades.However,the fact that the radar fails to resolve multiple closely spaced targets is increasingly prominent in various applications.The theory of ambiguity function occupies a very important place in the research on radar resolution.Meanwhile,many super-resolution theories trying to break through the Rayleigh resolution limit are being proposed.Though these super-resolution approaches are partially effective,their practical use is limited because of the presupposition.The traditional resolution theory ignores the polarization of the electromagnetic field.Polarization enables radars to have super-resolution capacity.The research on the relationship between polarization and resolution has major theoretical significance.In this paper,we analyze the effect of amplitude and phase on resolution.It is known that optimal resolution can be achieved with equal amplitude and opposed phase.On this basis,we present an innovative polarimetric zoom theory for radar super-resolution.Based on radar polarization modulation,the principle of super-resolution is presented by introducing the concept of a fullpolarization domain range profile.Additionally,we design an algorithm for multitarget detection and estimation using polarimetric zoom.Each target can be successfully detected and precisely measured.Finally,the simulation results demonstrate that the proposed approach is not sensitive to cross-polarization,and the resolution power can be improved by 20 times at high SNR.

关 键 词：极化调控 雷达超分辨 模糊函数 极化域变焦理论 全极化域距离像 

分 类 号：TN957.51[电子电信—信号与信息处理]