中文摘要：

从自由空间中的三阵子天线求入射电磁波极角和方位角的基本原理出发，结合电场各个分量与极化方式之间的关系给出了左手极化波计算波达角的公式，及地球表面上方三阵子天线判断入射波极化方向的方法；本文提出了一种新颖的滤除地面反射波的方法，保证了波达角的求解精度；利用获得的高精度的波达角和测得的电场强度，计算出了电磁波的各种极化参数，这些极化参数可以作为电离层研究和电磁波在电离层中传播研究的参考。

英文摘要：

Based on the principal theory of tripole antenna in free space to compute the polar angle and azimuth angle of the incident electromagnetic wave （EMW）, and the relations between each component of electric field and polarization, the formula for computing direction of arrival （DOA） of left-hand polarization electromagnetic wave and the method of determining the sense of the incident wave are presented. A novel method to filter out the reflected wave from the earth surface is put forward, which ensures the accuracy of the DOA, various polarization parameters are gained from DOA computed and electric field intensity, these polarization parameters serve as reference data for research of ionosphere and electromagnetic wave propagation in the ionosphere.