极化信息是电磁波的固有属性可以提高信号的传输效率和信息的提取精度是和信号方位信息同等重要的信息。电磁波在空间中任意一点的大小和方向均为时间的函数该函数即为电磁波的极化。一般可以根据电磁波的矢量端点形成的轨迹在垂直于传播方向的平面上的投影的形状将极化分为线极化、椭圆极化和圆极化其中若椭圆极化的投影椭圆的长轴与短轴相等此时椭圆极化即为圆极化且电场大小不变但电场方向一直变化；若椭圆极化的投影椭圆的短轴为

Polarization information is an inherent property of electromagnetic waves, which can improve the transmission efficiency of signals and the accuracy of information extraction. It is equally important information as signal directional information. The size and direction of an electromagnetic wave at any point in space are functions of time, which is the polarization of the electromagnetic wave. Polarization can be divided into linear polarization, elliptical polarization and circular polarization based on the shape of the projection of the vector endpoint trajectory of the electromagnetic wave on the plane perpendicular to the propagation direction. If the long and short axes of the elliptical polarization projection are equal, the elliptical polarization becomes circular polarization, and the magnitude of the electric field remains constant but the direction of the electric field keeps changing. If the short axis of the elliptical polarization projection is zero, the elliptical polarization degenerates into linear polarization, and the magnitude of the electric field changes but the direction remains constant. Therefore, circular polarization and linear polarization are two extreme cases of elliptical polarization. According to the direction of rotation of the electric field vector over time, elliptical polarization can also be divided into left-handed elliptical polarization and right-handed elliptical polarization. Similarly, for circular polarization, it can be divided into left-handed circular polarization and right-handed circular polarization. If the polarization information of a vector signal is written as a fixed function of time, the vector signal can be divided into unpolarized waves, completely polarized waves and partially polarized waves. Completely polarized waves have completely correlated horizontal and vertical components of the electric field vector, with a constant ratio between them. Partially polarized waves have incoherent horizontal and vertical components of the electric field vector, with a ratio that varies dynamically over time, and the polarization parameter is also a dynamic function of time. Unpolarized waves can be regarded as a special case of partially polarized waves, where the horizontal and vertical components of the electric field vector are completely uncorrelated, and they are defined as random polarized waves. For ease of discussion and analysis, the incoming signals assumed in this article are completely polarized waves.