盲分离算法和FRFT联合抗雷达主瓣干扰技术研究

A Study on Radar Mainlobe Jamming Suppression Technique Based on Method of BSS-FRFT Union

压制干扰信号从天线主瓣进入雷达接收机,会严重影响雷达的性能,通常的旁瓣抗干扰技术难以奏效。而基于盲源分离算法(BSS)的抗主瓣干扰技术在低信噪比条件下性能恶化,因此本文提出了BSS和分数阶傅里叶变换(FRFT)联合抗主瓣干扰的技术。文章首先利用经典的BSS算法分离接收到的主瓣干扰混合信号,然后对有线性调频(LFM)信号特征的分离信号进行FRFT变换处理,并在FRFT域滤波去除大部分噪声的能量,最后FRFT逆变换恢复出目标信号。仿真实验表明,新算法相比BSS的抗主瓣干扰算法对脉冲压缩以后的峰值信噪比有较大的改善,较大地提高了脉冲压缩雷达的检测性能,具有良好的应用前景。

If the suppress jamming pour into the mainlobe of radar antenna, it would severely degenerate the performance of radar. The common ECCM measures of sidelobe have no effect. But the performance of the technique of anti-mainlobe-jamming based on blind source separation algorithm would deteriorate in the condition of low signal to noise ratio. In this paper, we present the technique of anti-mairdobe-jamming based on BSS with the fractional Fourier transform de-noise. The mixed interference and target signal is separated by the classical BSS algorithm in the first of all. Then the signal separated which is a linear frequency modulation signal is dealt with FRFF and filtered to cut away the almost energy of noise in FRFF domain. The target signal is recovered by the FRFF opposite transform at last. The experiment of simulation indicates that it is a supe- rior improvement for the peak SNR after pulse compression for the new algorithm than the process of BSS. Because the detec- tion performanee of the pulse compression radar is enhanced preferably, the new algorithm can be applied in practice.