摘要
针对无限冲激响应(IIR)和有限冲激响应(FIR)数字滤波器在对鱼雷电磁引信的接收信号进行窄带滤波时均存在不同程度的缺陷,提出了一种采用Morlet组合小波构造带通滤波器的方法。该方法通过合理选择小波参数构造组合小波,可设计出具有零相位漂移、平顶通带和快速衰减过渡带的带通滤波器,同时利用组合小波的虚部是其实部的Hil-bert变换的特征,还可实现信号的包络检波。结合典型的电磁引信目标信号及背景干扰模型,在Matlab仿真环境中对上述方法进行了仿真分析。结果表明,采用Morlet组合小波的方法可在-5 dB的低信噪比的条件下有效滤除背景干扰,并获得精确的目标信号的检波包络,具有良好的应用前景。
Both infinite impulse response（IIR） and finite impulse response（FIR） digital filters are deficient in filtering the received signals of torpedo electromagnetic fuze. We therefore present a method to construct a band pass filter with Morlet combined wavelets. By appropriately selecting wavelet parameters, the band pass filter is designed with zero phase shift, fiat-topped passband, and rapid attenuation in transition band. Moreover, the signal envelope can be demodulated by making use of the feature that the imaginary part of the combined wavelets is the Hilbert transform of its real part. According to the representative models of electromagnetic fuze target signal and ambient noise, simulation analysis is carried out in Matlab simulation environment. The results show that our method can effectively eliminate the ambient noise in a low signal to noise ratio（SNR） condition down to-5 dB,and can accurately achieve target signal envelope.
出处
《鱼雷技术》
2009年第3期13-17,共5页
Torpedo Technology
关键词
鱼雷
Morlet组合小波
电磁引信
数字滤波器
检波
无限冲激响应
有限冲激响应
torpedo
Morlet combined wavelets
electromagnetic fuze
digital filter
demodulation
infinite impulse response （IIR）
finite impulse response（FIR）
