无线电工程

微波易于实现窄波束定向通信,其在电离层中的传播时受大气折射的影响,波束传播的方向会产生弯折。因此,微波的传播特性主要由大气折射率的变化决定,而大气折射率与相应传输层面的电子浓度有关。通过对线性条件下电离层临界频率和大气折射率公式的推导,并结合电离层电子浓度经验分布模型对电子浓度和大气折射率进行数值模拟,进而对电离层大气折射率的高度剖面图及其变化特性进行了分析,为微波卫星链路传播提供了理论参考。

The characteristics of microwave propagation through ionosphere is mainly determined by the diversification of the atmospheric refractive index,while the refractive index has positive correlation with the electron concentration at corresponding propagation layer.The critical frequency of ionosphere at linearity condition and the atmospheric refractive index formula are derived.And the numerical simulations are taken on the electron concentration and the atmospheric refractive index based on ionospheric electron concentration distributing model.Finally the diversification of the atmospheric refractive index relates to the altitude is also analyzed,which provides theoretic reference to practical microwave propagation through terrene-satetlite link.