一种电离层场向不规则体各向异性散射模型

电离层场向不规则体散射具有很强的方向性, 利用电离层场向不规则体散 射进行VHF频段超视距通信时, 需要准确可靠地确定其散射分布特性及路径损 耗等参数. 基于电离层不规则体场向散射的特点, 以地球地磁场为坐标系统, 提出了一种电离层场向不规则体各向异性散射模型, 该模型能够计算前向和后 向散射链路的路径损耗分布、时延展宽和相干带宽等参数, 同时运用该模型对 雷达横向截面的计算结果与已有文献的数据结果进行对比, 证明了该模型的准确性. 该模型能够计算电离层场向不规则体VHF频段的散射分布及路径损耗等参数, 为VHF散射通信链路的设计、布站提供依据和技术指导. 

An Anisotropic Scattering Model of Ionospheric Field-aligned Irregularities

As influenced by geomagnetic field, electron density fluctuations of ionospheric irregularities are highly elongated in the direction of geomagnetic field, and the scattering of the irregularities are also highly directional, which could be potentially used as long-distance communication circuits in VHF band. Based on the characteristic of ionospheric Field-Aligned Irregularities Scattering (FAIS), an anisotropic scattering model of ionospheric field-aligned irregularities is proposed in the geomagnetic reference frame. The parameters such as path loss, delay spread and coherence bandwidth of forward and back scattering are calculated by the model. The results of Radar Cross Section (RCS) predicted by the model have a good agreement with data in literatures. The model given herein can be helpful to construct ionospheric irregularities scattering communication systems in VHF band.