大气波导传播类型及特性分析

Analysis of the types and characteristics of atmospheric duct propagation

电磁波在大气中传播时,除了正常的折射外,在特殊条件下还会产生超折射现象,从而形成大气波导传播。利用大气波导,可以扩大探测、截收、通信和电子对抗等电子系统的有效作用距离,为远距探测、预警和通信提供条件。同时,也会形成诸如向外扩展的电磁盲区,使雷达系统的杂波增强等不利因素。要实现大气波导超视距传播,须对将电磁波在大气波导环境中的传播进行研究。通过对大气波导类型及形成条件、电磁波实现大气波导传播的必要条件的分析,用射线描迹方法研究了大气波导传播的8种类型,同时对其特性进行了分析,从而为电子系统在各种大气波导环境下的应用奠定了基础。

Besides the normal refraction, there also exists the super-refraction in the process of the electromagnetic wave propagation in the atmosphere under certain particular conditions; accordingly the atmospheric duct propagation is produced. The effective range of detection, interception, communication and electronic warfare of the electronic system can be expanded by using atmospheric duct, providing for long-distance detection, early warning and communication. Oppositely, the at- mospheric duct still has its disadvantages, for example, it forms the expanding electromagnetic shadow zone and increases the clutter of the radar system. In order to realize the over-the-horizon atmospheric duct propagation, it is necessary to clarify the state of the electromagnetic wave propagation in the atmospheric duct. By analyzing the duct types, the formation conditions and the necessary conditions during the realization of atmospheric duct propagation, eight types of atmospheric duct propagation, as well as the analysis of the characteristic, are being researched by the means of the ray-tracing, establishing the foundation for the application of electronic systems in various circumstances