LFM雷达移频干扰特征的消隐方法研究

The Study on Characteristic Blanking Technique in Frequency Shifting Jamming for LFM Radar

移频干扰是对抗LFM雷达的一种有效干扰方法,然而常规移频干扰的载波频偏特征可能被用来识别干扰信号,为此,该文提出一种新的干扰特征消隐方法。为了隐藏或者消除这个载波频偏,新方法将对干扰信号的脉宽进行一定的截短。此外,新方法还可以通过打乱载波频偏与干扰信号移频量的原有换算关系来破坏雷达对干扰信号的识别。和传统干扰信号相比,新方法在脉宽上将和目标回波有失配,但是这个失配损失是可以接受的。理论分析和仿真结果证明了该方法的正确性和有效性。

Shift-frequency jamming is an effective jamming to the Linear Frequency Modulation （LFM） radar. However, the feature of carrier frequency offset of the traditional shift-frequency jamming may be used to identify the jamming signal. So a new method is proposed to hide or subtract the feature of the traditional shift-frequency jamming in this paper. For the purpose of hiding or subtracting the carrier frequency offset, the pulse width of jamming signal will be truncated with a proper magnitude. Furthermore, the new method can also disturb original conversion relationship between carrier frequency offset and the frequency shifting of the jamming signal to reduce the ability of identifying false target. Compared with the traditional shift-frequency jamming, the new method has pulse width mismatch between the jamming signal and the echo. But the loss of the mismatch is acceptable. The new method is testified with the theory analysis and simulation results.