基于蒸发波导传播的雷达定位误差研究

Radar Locating Error Based on Propagation of Electromagnetic Wave in Evaporation Duct

大气参数满足一定条件(修正折射率梯度小于0)时会形成大气波导,利用大气波导可实现雷达的超视距探测。由于近海面易形成蒸发波导,利用蒸发波导实现雷达的超视距探测已成为目前舰船雷达最实用的方法之一。雷达电波射线在不均匀大气中传播时会产生折射误差,为提高舰船雷达的定位精度,必须研究雷达在蒸发波导中超视距探测时的大气折射误差。根据电波传播理论,利用电波射线描迹技术,建立了舰船雷达在蒸发波导中实现超视距探测时的大气折射误差模型。仿真实验表明,蒸发波导条件下雷达超视距探测目标时的大气折射误差较大,且计算时不能采用常规的折射误差计算方法。

Atmospheric duct occurs when the atmospheric parameters satisfy certain conditions.The over-the-horizon radar detection would be able to achieve by making use of the atmospheric duct.At present one of the most practical ways for ships is using evaporation duct at sea surface to realize the over-the-horizon radar detection.As the radio wave radiation can produce refraction error in uneven atmosphere,it is necessary to study the atmospheric refraction error for over-the-horizon radar detection in evaporation duct.According to radio wave propagation theory,the model of atmospheric refraction error for the over-the-horizon radar detection in evaporation duct was established with the ray tracing techniques.Simulation proved that atmospheric refraction error is relatively large when radar carries out over-the-horizon detection in the evaporation duct,and the conventional method is not applicable to calculate the refraction error.