摘要
为了提取高次频率耦合特征,定义了32维谱的概念,从理论上研究了32维谱的特有性质。理论研究表明:利用32维谱能完全抑制对称分布的噪声;利用复数信号的32维谱能分别提取参与4次频率耦合的分量和因4次频率耦合产生的新频率分量,也能分别提取参与二三对频率耦合的分量和因二三对频率耦合产生的新频率分量;利用实数信号的32维谱,可同时提取参与4次频率耦合、二三对频率耦合的分量和因频率耦合产生的新频率分量;无论是利用复数信号还是实数信号的32维谱,均无法提取频率独立的分量。基于实测数据的仿真实验表明:利用32维谱可有效提取水下目标辐射噪声的4次频率耦合与二三对频率耦合特征。
To extract higher order frequency coupling features, the conception of 3^-dimensional spectrum is firstly defined and its own properties are analyzed. 3 K-dimensional spectrum of complex signals can entirely suppress the symmetrically distributed noise. 31/2-dimensional spectrum of complex signals can extract the attended quartic frequency coupling components, the attended quadratic-to-cubic frequency coupling components, procreant frequency components for these coupling as well as their relative coupling intensities, respectively.31/2- dimensional spectrum of real signals can synchronously extract attended frequency coupling components, procreant frequency components for the coupling as well as their relative coupling intensity. However, 31/2-dimensional spectrum of complex or real signals can entirely suppress independent frequency components.
出处
《数据采集与处理》
CSCD
北大核心
2006年第3期292-296,共5页
Journal of Data Acquisition and Processing
基金
国家自然科学基金(60372086)资助项目
安徽省自然科学基金(050420304)资助项目
安徽省教育厅自然科学基金(2003KJ092
2005KJ008ZD)资助项目
安徽理工大学博士基金(2004YB05)资助项目
关键词
31/2维谱
高次频率耦合
相对耦合强度
二三对频率耦合
4次频率耦合
3K-dimensional spectrum
higher order frequency coupling
relative coupling intensity
quadratic-to-cubic frequency coupling
quartic frequency coupling
