基于FFT的有源欺骗干扰抑制

Suppression of Active Deception Jamming Based on FFT

基于DRFM的干扰机转发的有源欺骗干扰由于具有目标回波相似的脉压增益和目标行为,严重影响了雷达获取真实目标信息的能力。针对该类干扰,根据雷达接收机匹配滤波器得到雷达回波脉压信号矩阵,对该脉压信号矩阵按行FFT得到雷达回波脉压信号频谱矩阵。基于该脉压信号频谱矩阵目标回波频点估计设置带通滤波器,并对脉压信号频谱矩阵滤波得到目标回波脉压信号频谱矩阵估计。对该目标回波脉压信号频谱矩阵按行IFFT得到目标回波脉压信号矩阵,从而得到了基于FFT的有源欺骗干扰抑制方法。仿真结果表明当雷达回波脉冲数为60时,在Swerling I目标起伏下,该算法干扰抑制深度为20dB左右。在Swerling II目标起伏下,该算法干扰抑制深度为19dB左右。

Based on DRFM iammer, active deception jamming seriously affects the capability of the ra- dar obtaining true target information because of its similar pulse compression gain of target echo and vivid target behavior. In view of this kind of jamming, according to the radar receiver matched filter, pulse com- pression signal matrix（PCSM） of radar echo is obtained. By FFT of the PCSM row, pulse compression sig- nal spectrum matrix（PCSSM） of radar echo is got. Based on frequency point estimation of target echo in the PCSSM, band-pass filter could be obtained. According to the filter and the PCSSM of radar echo, the PG- SSM of target echo could be got. Then the PCSM of target echo is obtained by IFFT of the PCSSM row. So the suppression of active deception jamming based on the FFT is got. The simulation results show that when the number of radar echo pulses is 60, the signal-to-jamming ratio improving factor of the FFT algorithm is about 20dB in Swerling I, while it is about 19dB in Swerling II.