通过推导单频信号和线性调频(LFM)信号旋转角正负对称的分数阶Fourier变换(FRFT)模函数,得到一个有用的结论:单频信号正负对称旋转角的FRFT模值相等,模函数关于中心点对称,而对于LFM信号,其模幅度差别很大。根据此结论提出了一种基于观测信号正负对称旋转角的FRFT模之差的反辐射导弹(ARM)检测方法。此方法可以有效地消除载机信号的干扰。仿真结果表明,此方法在低信噪比下能有效地检测出ARM。
In this paper, the FRFT models with two symmetry inverse rotation angles of LFM signal and monochromatic signal are researched. A conclusion is obtained:the FRFT models with two symmetry in- verse rotation angles of LFM signal are different and the FRFT models of monochromatic signal are the same. Based on this characteristic, a new method for detecting ARM based on difference of FRFT models is pro- posed. In this method, the ARM carrier signal is suppressed effectively, and the detection performance is good in low SNR. Simulation results show its effectivity.