Nonlinear Time-Varying Spectral Analysis: HHT and MODWPT
نویسندگان
چکیده
Time-frequency distribution has received a growing utilization for analysis and interpretation of nonlinear and nonstationary processes in a variety of fields. Among them, two methods, such as, the empirical mode decomposition EMD with Hilbert transform HT which is termed as the Hilbert-Huang Transform HHT and the Hilbert spectrum based on maximal overlap discrete wavelet package transform MODWPT , are fairly noteworthy. Comparisons of HHT and MODWPT in analyzing several typical nonlinear systems and examinations of the effectiveness using these two methods are illustrated. This study demonstrates that HHT can provide comparatively more accurate identifications of nonlinear systems than MODWPT.
منابع مشابه
Empirical Mode Decomposition Based Instantaneous Spectral Analysis and its Applications to Heterogeneous Petrophysical Model Construction
Spectral analysis is an important step in seismic data processing and interpretation. The frequency contents of seismic traces vary with time due to the fact that the earth is non-stationary medium. Methods were available to improve the temporal and spectral resolution, such as windowed Fourier transform, wavelet transform, S-transform and Matching Pursuit Decomposition, etc. This paper describ...
متن کاملNonlinear and Non-stationary Vibration Analysis for Mechanical Fault Detection by Using EMD-FFT Method
The Hilbert-Huang transform (HHT) is a powerful method for nonlinear and non-stationary vibrations analysis. This approach consists of two basic parts of empirical mode decomposition (EMD) and Hilbert spectral analysis (HSA). To achieve the reliable results, Bedrosian and Nuttall theorems should be satisfied. Otherwise, the phase and amplitude functions are mixed together and consequently, the ...
متن کاملThe Hilbert–Huang Transform: A High Resolution Spectral Method for Nonlinear and Nonstationary Time Series
The Fourier transform remains one of the most popular spectral methods in time-series analysis, so much so that the word “spectrum” is virtually equivalent to “Fourier spectrum” (Huang et al., 2001). This method assumes that a time series extends from positive to negative infinity (stationarity) and consists of a linear superposition of sinusoids (linearity). However, geophysical signals are ne...
متن کامل○E The Hilbert–Huang Transform: A High Resolution Spectral Method for Nonlinear and Nonstationary Time Series
The Fourier transform remains one of the most popular spectral methods in time-series analysis, so much so that the word “spectrum” is virtually equivalent to “Fourier spectrum” (Huang et al., 2001). This method assumes that a time series extends from positive to negative infinity (stationarity) and consists of a linear superposition of sinusoids (linearity). However, geophysical signals are ne...
متن کاملPublication of Little Lion Scientific R&D, Islamabad PAKISTAN NON LINEAR AND NON-STATIONARY DATA ANALYSIS USING HILBERT-HUANG TRANSFORM
The newly developed method known as Hilbert-Huang Transform (HHT) is ideal for nonlinear and nonstationary data analysis as it is totally adaptive in nature. This paper will discuss the fundamentals of HHT method which consists of the empirical mode decomposition and Hilbert spectral transform. As a part of analysis, the HHT method is applied on two different data sets in which one is the annua...
متن کامل