伪码调相连续波引信压制式宽带干扰抑制的包络滤波方法

该文分析了几种典型压制式宽带干扰（BPSK干扰、调频干扰）对伪码调相连续波引信相关输出的影响。分析发现当干扰强度超出伪码调相引信的抗干扰容限时，其相关输出严重恶化，因此必须在相关检测前对上述干扰进行抑制。提出了一种通过包络滤波的宽带干扰抑制新方法。接收信号经过正交解调输出I，Q两路信号，由I，Q两路分量获得解调信号的瞬时包络和瞬时相位。包络序列在变换域通过门限滤波去除有用信号和白噪声成分从而得到干扰信号包络。利用滤波后的包络和瞬时相位重构出干扰同相信号，最后将干扰信号从I路放大信号中去除即得到所需信号。仿真分析发现该方法能较好地抑制干扰，尤其是对强干扰，相关输出得到明品改善。该方法计算简单，易于理解，容易工程实现。

The Oppressive Broadband Interference Excision through Envelope Filtering for Pseudo-random Code Phase Modulation Fuze System

The effects of several types of oppressive broadband interference (BPSK interference, FM interference) on pseudo noise coded fuze system are analyzed. It is found that the correlation output is deteriorated when the interference power is larger than the anti-interference limit of the fuze system. So it is very necessary to excise the above interference before correlation. A new simple technique of excising interference through envelope filtering is put forward. The received signal is quadrature demodulated to inphase and quadphase signal. The instantaneous envelope and phase are got with the inphase and quadphase signal. The envelope of interference is obtained by envelope notch filtering in the frequency domain. The interference is reconstructed using the notched envelope sequence and the phase sequence. Then the reconstructed interference is subtracted from the received signal. It is found by simulation that the technique proposed in this paper can effectively excise the broadband interference, especially for strong interference. And the correlation output is improved obviously. The technique is easy to be understood. It has low computational complexity and therefore is easy to realize.