对解线调处理的ISAR的相干干扰技术

逆合成孔径雷达(ISAR)通常采用解线调处理的方法来得到频域距离像.本文提出一种附加调制的相干干扰方法,即对接收的雷达信号产生附加的频率调制后转发,干扰谱就能覆盖距离像的频域范围,破坏ISAR一维距离成像;对频率调制后的信号再附加相位调制,就能破坏ISAR二维多普勒成像.这种干扰信号能获得一定的处理增益,因此能节省干扰功率.

Coherent Jamming Technique Countering ISAR

For the reduction of sampling bandwidth,Inverse synthetic aperture radar(ISAR) echoes are usually dechirped first in the receiver.Then the dechirped signal employs FFT to get the range image in frequency domain.In general,the bandwidth of the target image is much less than that of the radar signals.So the narrowband signal can be used to modulate the receiving signal.Coherent jamming is proposed for jamming ISAR.Some video signals modulate the receiving signal in frequency domain,then the resulting signal is retransmitted.The dechirped output of the coherent jamming will produce cover jamming.Thus,ISAR can not obtain the range image.The paper also studies the effect of phase modulated jamming on the Doppler image.The coherent jamming can obtain some processing gain,so it can save jamming power.Theoretical analysis and computer simulation justify the validity and efficiency of this jamming technique.