高频雷达自适应波束形成抗干扰研究

Research for interference suppression in HF radar based on ADBF

高频波段上分布的大量短波信号降低了高频雷达的探测性能,需要采用自适应波束形成技术加以抑制。但是,在高频雷达的相干积累时间内,短波干扰经过电离层反射传播后通常会呈现明显的空时非平稳性。为了适应这种非平稳性,要求在相干积累时间内自适应权向量应是时变的,同时能保持杂波的相干性。提出了基于递归最小二乘(RLS)的高频雷达自适应波束形成方法。该方法兼顾了短波干扰抑制和杂波相干性保持,而且递归运行,收敛速度快,数值稳定性高。实测数据处理证明了该方法的有效性。

The shortwave radio interferences in High-Frequency（HF） band severely degrade the detection performance of HF radar.The ADBF technique can be used to suppress the interferences.In the CIT of HF radar,however,the interferences exhibit spatially and temporally nonstationary when they propagate across the ionosphere.Therefore the weight vectors of ADBF are required to be time-variant during the CIT and at the same time the coherence of clutter has to be hold.The RLS-based ADBF of HF radar is presented in this paper.The novel approach can effectively suppress the shortwave interferences and simultaneously hold the coherence of clutter,moreover,it is of recursive computation,fast convergence speed and high numerical stabilization.Finally the effectiveness of the presented approach is demonstrated by real radar data.