时频分析和Fisher聚类的转发式干扰抑制算法

针对雷达对抗中转发式欺骗干扰的抑制问题,提出了一种基于时频分析和Fisher聚类的干扰鉴别及抑制算法。通过STFT变换,分析并提取了回波与干扰信号的时频特性差异,在信号检测基础上,采用Fisher聚类法实现了干扰与回波的分离,并通过时频滤波实现干扰抑制。仿真结果表明,能有效对抗频移调制实时转发干扰,当干扰与回波处于不同时辨单元时,可直接滤除干扰信号,且对干信比不敏感;处于相同时辨单元时,可有效抑制干信比小于25 dB的干扰信号。

A Suppression Arithmetic of Repeater Jamming Based on Time-Frequency Analysis and Fisher Clustering

In view of the suppression of transmitting deceptive jamming in radar countermeasure, this paper proposes a discrimination and suppression arithmetic based on time-frequency analysis and fisher clustering. Through STFT conversion, the paper analyzes and extracts the time-frequency characteristic of mixed signals by the arithmetic, and then distinguishes the jamming via fisher clustering. Finally, the arithmetic restrains the false targets through time-frequency filtering. The simulation results show that the arithmetic can restrain the deception jamming with frequency shift effectively. When the jamming and the echo are in different unites, the jamming can be filtered directly in any jam-to-signal ratio (JSR), and the interference can be suppressed whose JSR is under 25dB.