大型数字阵面子阵优化研究

发布时间：2018-03-25 11:36

本文选题：空时自适应处理　切入点：子阵优化　出处：《南京大学》2014年硕士论文

【摘要】：如何有效地抑制地杂波是机载预警雷达需要解决的首要问题。与地基雷达不同,机载雷达的平台运动会造成地杂波多普勒谱的扩展,杂波谱的扩展会覆盖低速目标,进而影响系统的目标检测性能。近年来,随着元器件技术和信号处理技术的发展,自适应杂波抑制技术从一维扩展到二维,空时自适应处理(STAP)因而成为了抑制杂波的关键技术并逐步进入工程实践阶段。该技术同时对来自一个相干处理间隔的阵面天线单元信号和脉冲信号进行处理,因而可以有效地提高地杂波和干扰环境下的目标检测性能。然而,相控阵阵面结构庞大,包含几百甚至几千个阵元,在目前的元器件技术和信号处理技术水平下还无法实现阵元级STAP处理。本论文研究了如何在空域降维,即如何将阵面划分为子阵才能获得最优系统性能的问题。本论文的主要工作如下：1.总结了一些已有的子阵优化工作,从栅瓣的形成、杂波自由度和非理想因素三方面分析了子阵划分带来的物理影响,进而提出了两类子阵优化准则：基于阵面结构和阵元加权准则、基于训练数据样本准则。2.构建了子阵优化问题的数学模型,将两类子阵优化准则转化为不同的目标函数,设计了专用的遗传算法对子阵优化问题进行了求解。3.使用大量仿真数据比较了两类优化准则得到的子阵划分形式对系统性能的影响,通过比较结果分析了两类子阵优化准则的适用范围。本论文提出的两类子阵优化准则和子阵优化算法在工程实践中都有一定价值,也可以给相关领域的研究提供借鉴。
[Abstract]:How to suppress ground clutter effectively is the first problem to be solved for airborne early warning radar. Different from ground radar, the platform sports of airborne radar results in the expansion of Doppler spectrum of ground clutter, and the expansion of clutter spectrum will cover low speed targets. In recent years, with the development of component technology and signal processing technology, adaptive clutter suppression technology extends from one-dimensional to two-dimensional. Space-time adaptive processing (STAP) has thus become a key technology for clutter suppression and has gradually entered the stage of engineering practice, which simultaneously processes both array antenna unit signals and pulse signals from a coherent processing interval. Therefore, the performance of target detection in ground clutter and jamming environment can be improved effectively. However, the phased array has a large structure, which contains hundreds or even thousands of elements. At the present level of component technology and signal processing technology, the array element level STAP processing can not be realized. In this paper, we study how to reduce the dimension in the spatial domain. That is, how to divide the array surface into subarrays to obtain the optimal system performance. The main work of this paper is as follows: 1. The physical effects of subarray partitioning are analyzed from three aspects of clutter degree of freedom and non-ideal factors, and two kinds of subarray optimization criteria are proposed: based on array plane structure and matrix element weighting criterion. Based on the training data sample criterion. 2. The mathematical model of subarray optimization problem is constructed, and the two subarray optimization criteria are transformed into different objective functions. A special genetic algorithm is designed to solve the submatrix optimization problem. 3. Using a large number of simulation data, the effects of the submatrix partition form obtained by the two optimization criteria on the system performance are compared. The application range of two kinds of subarray optimization criteria is analyzed by comparing the results. The two subarray optimization criteria and subarray optimization algorithms proposed in this paper have some value in engineering practice and can also be used for reference in the research of related fields.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN959.73

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