摘要
分析了小波多分辨率分解方法引起的频率混叠的问题,提出了直接采用窄带FIR滤波的方法提取感兴趣的数据,然后利用Morlet复解析小波变换方法提取螺旋桨轴频。通过设置合适的中心频率和带宽,提取调制信号的包络,对包络信号进行谱分析,提取螺旋桨的轴频等信息,对于推算目标速度具有重要价值。
The limitation of frequency overlap existing in multi-resolution wavelet decomposition is analyzed. And a narrowband FIR filter method directly to extract interested data is proposed. By using Morlet complex resolution wavelet transform and setting appropriate band and center frequency the envelope of modulated signal is extracted and then analyzed with frequency spectrum method, finally the screw propeller shaft frequency, which is the important value for object speed calculation, can be obtained.
出处
《声学技术》
CSCD
2010年第1期32-36,共5页
Technical Acoustics
关键词
小波分解
FIR滤波
MORLET小波
调制谱
轴频
multi-resolution wavelet decomposition
FIR filter
Morlet wavelet
modulation spectrum
shaft frequency
