基于STFT和时变滤波的调频干扰抑制方法

FM Interference Suppression Based on STFT and Time-varying Filtering

分析调频(FM)干扰对伪随机二相编码连续波(PRC-CW)雷达相关检测性能的影响,当FM干扰超出伪码调相雷达自身抗干扰容限时,相关输出严重恶化。针对上述问题,考虑到伪码在时频平面上是近似均匀和平坦的,而FM干扰则具有较好的时频聚集性,提出了基于STFT和时变滤波的FM干扰抑制方法。对不同信干比(SJR)情况下干扰抑制前后的相关输出进行的仿真分析表明:该方法能够有效去除干扰,相关输出得到显著改善。

The influence of FM interference on correlation detection performance of the pseudo random code continuous wave （PRC-CW） radar is analyzed. It is found that the correlation output deteriorates greatly when the FM interference exceeds the anti-interference limitation of the radar. According to the fact that the pseudo random code is occupying the whole time frequency plane whereas the FM interference signal is well concentrating on the TF plane,a method of FM interference suppression is proposed based on STFT and time-varying filtering. The correlation output under different signal-lamming ratio （SJR） situations is simulated and the result shows that the method can effectively suppress the FM interference and improve the correlation output significantly.