【作者】 卢剑奇；

【导师】 赵拥军；

【作者基本信息】 解放军信息工程大学 ， 信号与信息处理， 2006， 硕士

【摘要】 雷达信号的建模与仿真在雷达系统的设计过程中具有重要地位。本课题分析了雷达接收的目标回波信号和杂波信号的统计模型，并对它们进行了计算机仿真。 在目标回波的仿真过程中，第一，以雷达方程为基础，对目标回波的数学表达式进行了深入分析。第二，阐述了雷达目标截面积(RCS)确定性模型的三种主要估算方法，以及几种简单形状几何目标的RCS计算公式和微波波段常见目标平均RCS数据。分析了雷达RCS的统计模型—Swerling模型的数学表达式，并给出了产生Swerling起伏的方法。第三，阐述产生均匀分布随机序列的两种方法：平方取中法和线性同余法的基本原理。通过对它们的结果进行比较，决定采用线性同余法来产生(0，1)均匀分布随机序列。第四，本文详细阐述了基本线阵原理，对等距线阵模型接收的回波信号进行了仿真。第五，根据目标运动轨迹，通过数学推导得出目标在线阵平面内做直线运动时的瞬时波达方向表达式。 本文对相干相关杂波模型进行了仿真。第一，阐述了零记忆非线性变换法和球不变随机过程法的基本思想及四种不同的幅度分布(瑞利分布、对数正态分布、韦布尔分布、K分布)在雷达杂波仿真中适用的不同场合。第二，分析了设计成形滤波器的三利，方法：AR模型法、最小相位法和频率抽样法。在比较了三种方法产生序列的相关特性之后，选择了相关性能最好的频率抽样法来设计成形滤波器。第三，本文深入分析了功率谱为高斯谱、幅度分别服从上述四种分布的杂波模型。同时介绍了较能贴近雷达杂波物理成因的非中心x~2伽马分布的产生原理。第四，对各种杂波模型进行了计算机仿真，得到了比较满意的结果。更多还原

【Abstract】 The Modeling and Simulation of radar signal plays an important role in the design of modern radar system. This paper analyses the statistical model of target echo and clutter received by radar.In the simulation for target echo, First we analyse the mathematical expression for radar target echo on the base of radar equation. Second, presenting three main calculational methods of the deterministic model of Radar Cross Section(RCS), and introducing the calculational formula for some simple object, some average RCS data of familiar objects in microwave band. Meanwhile, the statistical model of RCS—Swerling model are studied and the method to produce the Swerling sequences be given. Third, two algorithms for producing uniform distribution are analysed thoroughly by us—mid-square method and linear congruential method. Through the comparision of the performance of the two algorithms, we select the latter to produce the uniform distribution sequence in (0,1). Fourth, presenting the primary principle of line array and simulating the target echo received by ULA. Fifth, we derive the mathematical equation of the instantaneous DOA, when the target moving in line and in the same plane as ULA.This paper simulates the correlated-coherent radar clutter model. First, presenting the basic theory of zero memoriless nonlinear method and sphere invariable random process method、 the different fields where the four amplitude distributions(rayleigh、 log-normal、 weibull、 K) can be applied in. Second, analyzing three algorithms to design shaping filter: AR modele、 minimun phase、 frequency sampling. After comparing the correlation performance of sequences which are generated in these algorithms separately, we decided to use frequency sampling method has the best performance to design shaping filter. Third, this paper analyse clutter models which submit Gauss power spectrum and forenamed four amplitude distributions. Meanwhile, we introduce the noncentral chi-square gamma distribution that can interpret the physical reason of radar clutter better. Fourth, we simulate different clutter models, the result is useful for practical work.更多还原