A DIRECT EVALUATION OF MONO-COMPONENTS BY INSTANTANEOUS FREQUENCY

作者：Niu, Kaifu^*; Peng, Lizhong; Peng, Silong

来源：International Journal of Wavelets, Multiresolution and Information Processing, 2012, 10(3): 1250028.

DOI：10.1142/S0219691312500282

• Mono-component signal
• instantaneous frequency
• envelope
• offset of local extremum
• weak intrinsic mode function

We present a new criterion based on instantaneous frequency (IF) to distinguish mono-components (MCs). We first notice that the "offset of local extremum" caused by low-frequency envelope is often significant on envelope extraction, which determines the calculation of IF for MCs. We estimate the upper and lower bounds of the offset for a general family of signals. Conducted by the offset estimation, we propose a direct and effective algorithm to calculate IF. Our algorithm, which is based on an empirical pursuit of knots and natural splines, provides an accurate estimation of the envelope and derives a well-behaved IF. A theoretical explanation for the good approximation of proposed envelope is also stated. Experiment results show the fast convergence of our algorithm, which leads to a reliable IF and local mean to provide a flexible criterion for MC classification. We emphasize that it is important to pursue a certain balance among different requirements to define MC depending on specific applications.

• 出版日期2012-5
• 单位中国科学院; 北京大学