【作者】 马学文；

【导师】 黄际英；

【作者基本信息】 西安电子科技大学 ， 无线电物理， 2001， 硕士

【摘要】 本篇论文目的是通过研究雨杂波中的目标的极化特性来寻找收发雷达的最佳化方式以提高目标的接收信号或增强接收信杂比。首先根据国内外学者已有的究成果，将雷达极化学里常用概念给以重新定义或描述，本文从单个雨滴的散入手，用统计的方法计算出雨区的Mueller散射矩阵，并对后向散射功率从极的角度做了分析，将其分成完全极化部分和完全非极化部分，这对于分析雷达杂波的接收有重要的指导意义。提高雷达目标的回波功率和提高信杂比（SCR在雷达检测中有十分重要的意义，本文就雷达回波功率的问题从变极化的角度了分析。根据散射波的性质不同，雷达目标可分为相干目标和非相干目标。对相干目标，利用“三步法”的方法可以得到雷达最佳极化；对于非相干目标，中用Kennaugh矩阵得到散射功率，然后用拉格朗日乘子法求出最佳极化和最接收功率。最后，我们同样用Kennaugh矩阵分别表示出目标信号和杂波的接功率，然后将信杂比用收发雷达的极化状态表示出来，用拉格朗日乘子法结合代法求出最优化的雷达的极化状态。这种优化往往是以削弱目标信号的接收换的，但这对于雷达目标检测来说是必要的。需要注意的是，上面我们考虑的只共极化通道和交叉极化通道的后向散射接收功率，所以收发雷达的极化状态不是独立的。更多还原

【Abstract】 The purpose of this paper is to improve the received signal and SCR (the ratio of signal to clutter) by study of the polarization character of the target in rain clutter and finding the optimum polarization states of the antennae. In this paper, all notions and prescripts are redefined based on the existed documents. In ohier to obtain the Mueller matrix in rain area, the back scattering character of one raindrop is studied, and the Mueller matrix is then obtained by means of statistics. The power of the reflected waves are classified according to the polarization states, and it is a matter of great significance. To enhance the reflected signal of the radar target, which is important in the field of radar target recognition, the three-step method and Lagrange factor method are used. It is also discussed how to get the optimum polarimetric state of the antennae when the SCR is optimum. Although it could weaken the signal of the target in clutter, it is reasonable to radar target detection. It should be noted that in this paper the polarimetric states of receiving and transmitting antenna are same or cross which are not independent.更多还原