基于变分信号分解的脉冲多普勒雷达抗扫频式干扰方法

Anti-sweep-jamming Method for PD Radar Based on Variational Signal Decomposition

针对脉冲多普勒(Pulse Doppler,PD)雷达遭受扫频式干扰时,接收机被干扰信号饱和导致的雷达虚警或漏警问题,分析扫频式干扰作用下PD雷达中频信号特征,提出基于变分信号分解的PD雷达抗扫频式干扰方法。利用目标回波时域稀疏性及干扰信号的频域窄带特性,通过极大极小惩罚项和2阶变分惩罚项分别约束中频信号中的目标回波脉冲串分量和干扰分量,设计了基于交替方向乘子法的迭代算法求解优化问题各分量。保留目标回波脉冲串分量,滤除扫频中频分量,从而抑制干扰对雷达的影响,并通过仿真和实测数据验证方法的有效性。研究结果表明:所提抗干扰方法在信干比-20 dB扫频式干扰作用下能够有效抑制扫频式干扰对PD雷达的影响,显著提高PD雷达的抗干扰性能。

When the pulse Doppler radar is subjected to sweep-jamming,its receiver channel is saturated by the jamming signal,which causes the radar false alarm or miss alarm.Aiming at the above problem,an IF signal model of pulse Doppler radar under sweep-jamming is established,and a separation method of target echo and jamming based on signal variational decomposition(SVD)is proposed.The proposed method uses total variation regularization to decompose the IF signal into two components:pulse and low-frequency narrowband signal.The pulse corresponds to the target echo,while the low-frequency narrowband signal corresponds to the jamming.The ow-frequency narrowband signal and noise are eliminated,and the pulse is retained and processed to detect the real target.The effectiveness of SVD was verified by simulation.The results show that the method can still effectively separate the target echo and jamming under the condition that signal-to-jamming ratio is lower than-20 dB,and greatly improve the target detection ability of pulse Doppler radar under the effect of sweep-jamming.