交叉极化比对平板天线动中通收发系统性能的影响

Influence of the Cross Polarization Ratio on the Performance of Transceiver System in Flat-Antenna SOTM

交叉极化比是平板天线卫星动中通系统设计和加工的产物,它是衡量系统性能的一项重要参数。针对交叉极化比导致的极化误差,重点研究了交叉极化比对平板天线卫星动中通信号发射和接收系统的影响。通过理论推导和实际测试,结果表明不合理的交叉极化比会导致较大的极化误差,降低发射系统的发射效率,减小接收系统信噪比,导致系统性能恶化。为减小交叉极化的影响,建议等效口径0.6 m的平板天线卫星动中通的交叉极化比指标不小于30 d B。

Polarization isolation ratio is the result of the design and manufacture error of the flat-antenna SOTM sys- tem, and it is an important parameter to measure the performance of the antenna. For the polarization isolation ratio caused by polarization isolation, the effect of polarization isolation ratio on the signal transmitting and receiving system of the flat-an- tenna SOTM is studied. Through theoretical deduce and test, the result shows that unreasonable polarization isolation ratio would lead to large polarization error, reduce the transmission efficiency of the system and the signal to noise ratio of the re- ceiving system, and finally result in deterioration of the system performance. In order to reduce the influence of cross polari- zation, the proposed polarization isolation ratio index of the flat-antenna SOTM system whose eqtfivalent aperture is 0.6 m is not less than 30 dB.