摘要
平滑能量分离算法能够跟踪调幅调频信号的瞬时频率,结合广义解调和复解析Gabor滤波器的优点能够克服平滑能量分离算法只适用于单分量窄带信号以及对噪声敏感的局限性。理论分析了负频干扰对传统广义解调多分量分离方法的影响,在此基础上提出了一种新的基于广义解调的平滑能量分离算法,该方法利用广义解调将非平稳信号转化为准平稳信号,再通过复解析Gabor滤波器对其进行滤波以达到单分量信号分离的效果,分离出来的准平稳信号无需进行逆广义解调,直接采用平滑能量分离算法求取瞬时频率,经过频率补偿得到原始信号的瞬时频率。仿真和试验结果表明该方法能够克服负频率干扰,且比传统方法具有更高的解调精度,进一步扩大了平滑能量分离算法的应用范围。
The smoothed energy separation algorithm can track the instantaneous frequency of amplitude modulation and/or fre quency modulation signal, but it is subject to narrowband mono-component signal and sensitive to noise. Combining the virtues of generalized demodulation and Oabor filter, the limitations of the smoothed energy separation algorithm can be eliminated. The cause of negative frequency interference after generalized demodulation of multi-component signal is analyzed. A new smoothed energy separation algorithm based on generalized demodulation is proposed. By generalized demodulation, non-sta tionary signal is transformed into quasi-stationary signals, and the smoothed energy separation algorithm is used directly to estimate the frequency of the quasi-stationary signal which extracted by complex Gabor filter. Then, without reverse generalized demodulation needed, the instantaneous frequency of the original non-stationary signal can be obtained lay frequency compensa tion. The simulation and experimental results show that the proposed method can eliminate negative frequency interference and has higher demodulation accuracy comparing with traditional method, which extends the application range of energy separation algorithm.
出处
《振动工程学报》
EI
CSCD
北大核心
2014年第2期281-288,共8页
Journal of Vibration Engineering
基金
国家自然科学基金资助项目(51005078
51075150)
广东省博士启动基金资助项目(S2011040003851)
华南理工大学中央高校基本科研业务费资助项目(2012ZM0045
2012ZM0044)
关键词
信号分析
瞬时频率
能量算子
广义解调
GABOR滤波
signal analysis； instantaneous {requeney； energy operator； generalized demodulation； Gabor filter
