该文研究了线性调频(LFM)信号和单频信号分数阶Fourier变换(FRFT)模函数的一些性质,根据这些性质提出了两种基于FRFT模之差的海杂波背景下匀加速运动目标检测的新方法。一种方法利用接收信号与其延时信号的FRFT模之差,另一种方法利用接收信号正旋转角的FRFT模与负对称旋转角FRFT模的镜像之差。两种方法能较有效地抑制海杂波,对信杂比有一定的改善,在低信杂比下具有较好的检测效果。对实测海杂波数据进行仿真,证实了两种方法的有效性。
In this paper, the characteristic of FRFT modules about LFM signal and monochromatic signal is researched. Based on this characteristic, two new methods based on difference of FRFT modules for moving target detection are proposed. One is based on difference of FRFT modules of echo signal and its time-lapse signal. The other is based on difference of FRFT modules with two symmetry inverse rotation angles of echo signal, and one of the FRFT modules has been overturned. In these methods, sea clutter is suppressed effectively. SCR can be improved to some extent, and the detection performance is good in low SCR. Finally, simulation results show the effectivity of proposed methods.