高频地波雷达天线阵抗电离层干扰

Adaptive nulling of ionospheric self-interference for HFSWR

高频表面波雷达是近年发展起来用于超视距监测大面积海洋环境的工具,但由于天线本身的特性和天线场的限制,发射天线辐射波束E面有一定的宽度或向上翘起一定角度,其辐射的电磁波能量除了沿海面绕射传播外,还有一部分能量以一定的角度向上半空间辐射,与电离层和所经路径上的散射体相互作用后,其后向散射信号又以原路径回到雷达,并对雷达形成严重的自干扰。本文基于自适应天线理论,在对功率倒置算法改进的基础上,介绍了一种自适应对消电离层自干扰新方法,雷达现场观测实验表明,本方法可以抑制电离层自干扰。

HF surface wave radar （HFSWR） as an effective tool inspecting the environment of the ocean in beyond-the-horizon area has been developing in recent years. However, because the radiating beam of transmitting antenna is of certain width in the E plane and inevitably turns up some degree, its electromagnetic radiating power propagates not only along the sea surface but also to the upper space, and as a result, after interacting with ionosphere or scattering object on its path, the backscattered signal then returns to the radar in the same coming path. Based on the performance for suppression of interference and eigenspace analysis, this paper explains the essence of power inversion array. The algorithm proposed can increase the depeth of the null in the direction of the weak interference. An effective method for ionosphere interference suppression in HF surface wave radar based on an improved power inversion algorithm is presented. Experimental results acquired with the HF system OSMAR confirm that the method can achieve effective ionosphere interference suppression.