极化通道扩展和盲源分离联合抗移频干扰技术

多次移频干扰是一种有效的对抗线性调频(LFM)脉冲压缩雷达的相干干扰样式,应用于自卫式干扰时,能够形成多个超前和滞后分布的假目标。提出利用盲源分离(BSS)的方法来分离回波和干扰信号,并通过频率补偿实现对干扰的抑制。首先分析了利用正交极化辅助天线扩展接收通道的可行性,其次建立了通道扩展后的雷达接收信号模型,讨论了回波与干扰信号的可分离性,最后研究了基于最大信噪比盲源分离和频率补偿的干扰抑制方法,并讨论了干扰机附加噪声对抗干扰效果的影响。仿真结果表明本文提出的方法在干信比为20 d B时,仍可以有效地从回波和干扰混叠信号中提取出目标回波信号,从而实现对主瓣移频干扰的对抗。

Shift-frequency jamming suppression technique based on polarized channel expanding and blind source separation union

Multiple shift-frequency jamming is an effective coherent jamming type to linear frequency modulation (LFM) pulse compression radar,which could produce multiple false targets before and after real target when it is applied in self-defense jamming.Considering the jamming suppression problem,a method based on blind source separation (BSS) to separate echo and jamming signals and frequency compensation to suppress jamming signal is proposed.First,the feasibility of cross polarized channel expanding was illustrated.Second,a radar-receiving-signal model was established after channel expanding.The separability of echo and jamming signal was discussed.Finally,the jamming suppression method based on the maximum signal-tonoise ratio blind source separation and frequency compensation was studied,and the influence of accessional noise from jammer was analyzed.Simulation results show that the proposed method could extract the target echo signal from the mixed signal effectively even when the jamming-to-signal ratio is 20 dB,which will suppress the main lobe shift-frequency jamming.