MIMO雷达低空目标检测及参数估计研究

发布时间：2018-04-16 04:08

本文选题：MIMO雷达 + 低空检测　；参考：《国防科学技术大学》2014年博士论文

【摘要】：低空飞行目标检测及跟踪作为雷达面临的四大威胁之一,至今未能有效的解决。多发多收(Multi-Input Multi-Output,MIMO)雷达做为近年备受关注的新雷达体制。MIMO雷达利用分集增益在目标检测、参数估计、目标跟踪、目标识别及抗干扰等方面较之传统雷达有着明显的优势。基于以上认识,MIMO雷达可以做为解决低空飞行难目标检测的技术途径。近年来国内外学者对MIMO雷达在目标检测、成像识别、参数估计进行了广泛深入的研究,然而基于MIMO雷达技术的低空目标检测及参数估计却很少涉及。为解决了低空目标检测及参数估计问题,论文围绕低空MIMO雷达理论模型、低空MIMO雷达检测器设计及低空MIMO雷达参数估计等关键问题展开研究,主要工作概括如下:第一章:首先阐述了低空目标检测及跟踪研究背景和意义,介绍了目前低空目标检测及跟踪的研究现状及MIMO雷达概念、分类以及其在目标检测领域的应用;归纳和总结了低空目标检测若干关键技术问题。第二章:以目前广泛采用Swerling目标模型为基础,研究MIMO雷达对低空Swerling目标的检测性能。首先推导了考虑大气折射和地球曲率的反射系数;介绍了MIMO雷达低空多径信号模型,推导了低空非起伏目标和起伏目标的检测概率和虚警概率,并通过仿真实验分析了MIMO雷达对低空Swerling目标模型的检测性能。为了从理论上证明MIMO雷达在低空目标检测的优势,第三章主要分析对比了MIMO雷达和相控阵雷达在低空目标检测的性能。首先分别推导了MIMO雷达和相控阵雷达低空多径信号模型;运用奈曼-皮尔逊(Neyman-Pearson)准则分别推导了MIMO雷达和相控阵雷达的低空检测概率和虚警概率;最后以相对熵为准则,分别分析了MIMO雷达和相控阵雷达的系统设计问题。理论分析和实验结果表明:对于低空目标检测问题,MIMO雷达要优于相控阵雷达,且MIMO雷达检测性能还跟天线数目、目标高度有关。低空雷达背景杂波模型常采用复合高斯模型。第四章研究了基于复合高斯杂波模型的低空MIMO雷达检测器设计问题。首先建立低空MIMO雷达多径矢量信号模型;在此基础上,设计了二次线性广义似然比检测器、广义似然比检测器和Rao检测器三种检测器,并分析三种检测器的低空检测性能。研究发现,GLRT和Rao检测器都具有恒虚警率特性(Constant False Alarm Rate,CFAR),二次线性广义似然比检测器检测器的低空检测性能要优于广义似然比检测器和Rao检测器,多径效应在低空检测重要性;雷达天线和目标高度都对低空检测性能有着显著地影响。第五章:针对期望最大化(Expectation-Maximization,EM)算法收敛慢的问题,本章提出了基于参数扩展期望最大化(Parameter-Expanded ExpectationMaximization,PX-EM)的MIMO雷达低空运动目标参数估计方法。主要内容包括:(1)推导了MIMO雷达低空运动目标多径信号模型,为低空参数估计奠定了理论基础;(2)针对目标参数和杂波参数的联合估计问题,提出了最大似然估计算法;(3)针对未知参数,提出了基于PX-EM算法的最大似然估计算法;(4)分别推导了纹理分量服从伽马分布和反伽马分布的克拉美-罗下界。第六章:总结了全文工作,并提出了若干需要进一步研究的问题。综上,论文以近年来深受关注的MIMO雷达为研究对象,在系统概念、理论模型、系统设计、检测器设计及参数估计等方面进行了初步探索。本文的研究成果将进一步丰富MIMO雷达理论体系,对认识、理解低空目标检测和参数估计都有一定的参考价值。
[Abstract]:Low altitude target detection and tracking is one of the four major threat to radar, failed to effectively solve so far. MTMR (Multi-Input Multi-Output MIMO) radar is of concern in recent years new radar.MIMO radar system with diversity gain in target detection, parameter estimation, target tracking, target recognition and anti-jamming is the traditional radar has obvious advantages. Based on the above understanding, MIMO radar can do to solve the low altitude target detection difficult approach. In recent years, domestic and foreign scholars on the MIMO radar in target detection, image recognition, parameter estimation was carried out extensive and in-depth research, but the estimation of low altitude target MIMO radar detection and parameter based on rarely involved. In order to solve the low altitude target detection and parameter estimation problem, the low altitude radar MIMO model, low MIMO and low M radar detector design Study on the key problems of IMO radar parameter estimation, the main works are summarized as follows: the first chapter: first elaborated the low altitude target detection and tracking research background and significance, introduces the current low altitude target detection and tracking the status quo and Research on MIMO radar concept, classification and its application in the field of target detection; and summarized some key problems low altitude target detection technology. The second chapter: the current widely used Swerling target model based on the detection performance of MIMO radar for low altitude target Swerling. Firstly, considering the reflection coefficient of atmospheric refraction and the curvature of the earth; the MIMO of low altitude radar multipath signal model, detection probability and false alarm probability is low and non fluctuating targets the ups and downs of target, and analyze the detection performance of MIMO radar for low altitude target Swerling model through simulation experiments. In order to MIMO from the theory of Shanghai Ming Lei In the low altitude target detection, the third chapter mainly analyzed the performance of MIMO radar and phased array radar in the low altitude target detection. Firstly, the MIMO radar and phased array radar low altitude multipath signal model are derived by Naiman; Pearson (Neyman-Pearson) criterion is derived MIMO radar and phased array radar low detection probability and false alarm probability at last; relative entropy as the criterion, analyzes system design problems of MIMO radar and phased array radar. Theoretical analysis and experimental results show that for the problem of low altitude target detection of MIMO radar is superior to the phased array radar, and the detection performance of MIMO radar with antenna number, target height. Low altitude radar clutter model is often used to composite the Gauss model. The fourth chapter studies the composite Gauss clutter model for low altitude radar detector design based on MIMO. Firstly, the establishment of low MIMO ray As the vector signal multipath model; on this basis, designed two linear generalized likelihood ratio detector, generalized likelihood ratio detector and the Rao detector three detectors, and analysis of low altitude detection performance of the three detectors. The study found that GLRT and Rao detectors have constant false alarm rate (Constant False Alarm Rate, CFAR). Two linear generalized likelihood ratio of low altitude detection performance of the detector detector is better than that of the generalized likelihood ratio detector and Rao detector, the multipath effect in the low altitude detection importance; radar antenna and the target height of low altitude detection performance has a significant influence. The fifth chapter: Based on the expectation maximization (Expectation-Maximization, EM) the problem of slow convergence of the algorithm. The chapter is put forward based on the expectation maximization (Parameter-Expanded expanded parameter ExpectationMaximization, PX-EM) estimation of low altitude targets MIMO radar parameter method. The contents include: (1) low altitude targets MIMO radar multipath signal model is derived, which laid a theoretical foundation for the parameter estimation of low altitude; (2) estimation of target parameters and clutter parameters, proposed a maximum likelihood estimation algorithm; (3) with unknown parameters, proposed a maximum likelihood estimation algorithm PX-EM algorithm based on the derived; (4) texture component to gamma distribution and inverse gamma distribution of the CramerRao bound. The sixth chapter summarizes the work, and puts forward some problems that need further research. To sum up, the MIMO radar nearly years has attracted much attention as the research object, in the system concept, theoretical model the system design, has carried on the preliminary exploration of detector design and parameter estimation. The results of this study will further enrich the theoretical system of MIMO radar, understanding, understanding of low altitude target detection and parameter estimation are certain Reference value.

【学位授予单位】：国防科学技术大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN958

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