利用线极化天线快速测量圆极化天线轴比的方法

Fast measuring axial ratio of circular polarization antennas based on linear polarization antenna

针对轴比测试需要连续旋转线极化天线极化轴,在高频段旋转关节难以消除高速旋转带来的电缆抖动所引起的幅度和相位不一致性,提出了一种快速、精确测量圆极化天线轴比的测试方法。基于椭圆极化波的正交分解理论,该方法利用线极化天线对待测圆极化天线进行两组正交的线极化幅度测量,通过计算得到圆极化天线的轴比等极化椭圆参数的信息。在此基础上又提出了只用三个线极化分量测量圆极化天线轴比的方法。通过在微波暗室中对圆极化天线进行多次测试,验证了该方法的有效性。该方法提高了圆极化天线的测试效率,降低了测试难度,对于工程应用有重要的应用价值。

Axial ratio （AR） test requires continuous rotation of polarization axis of linear polarization（LP） antenna, however high-speed rotation of rotary joint brings cable jitter, which causes inconsistencies between amplitude and phase. Since it is difficult to eliminate the jitter at high frequency, a fast and accurate measurement method of the AR of CP antennas was presented. The method, which is based on the orthogonal decomposition theory of elliptically polarized wave, employs LP antenna to measure two groups of orthogonal LP amplitude of the CP antennas under test. Therefor axial ratio of circularly polarized antennas and other parameters of elliptic polarization can be obtained by calculating. And on this basis, an innovative method of measuring the AR of CP antennas using only three linear polarization components was proposed. By measuring CP antennas in an anechoic chamber repeatedly, the method was proved to be effective. This method can increase the efficiency of measuring CP antennas, ease the difficulty level of test, and is of great importance to engineering application.