This paper describes a new technique, called the empirical mode decomposition (EMD), that allows the decomposition of one-dimensional signals into intrinsic oscillatory modes. The components, called intrinsic mode functions (IMFs), allow the calculation of a meaningful multicomponent instantaneous frequency. Applied to a seismic trace, the EMD allows us to study the di erent intrinsic oscillato...

Abstract : In this paper we show that a complex dynamic representation (logenvelope and instantaneous frequency) can be used efficiently to compress the spectrum and band−shift a discrete−time signal. The original method and algorithm conceived here do not violate the amplitude−phase relationships typical of natural sound signals. This is achieved by simultaneous modification via transmapping o...

Lai et al. [Phys. Rev. E 62, R29 (2000)] claim that the angular velocity of the phase point moving along the chaotic trajectory in a properly chosen projection (the instantaneous frequency) is intermittent. Using the same examples, namely the Rössler and the Lorenz systems, we show the absence of intermittency in the dynamics of the instantaneous frequency. This is confirmed by demonstrating th...

The major impulse-like excitation in the speech signal is due to abrupt closure of vocal folds, which takes place at glottal instant (GCI) or epoch each cycle. GCIs are used many areas science and technology, such as prosody modification, voice source analysis, formant extraction synthesis. It difficult observe these discontinuities (corresponding GCIs) because superimposed time-varying respons...