Publication 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 annual mean global surface temperature anomaly and the other is the noise component measured by the Equatorial Atmosphere Radar located in Indonesia. The analysis of two data sets indicates that the HHT method is able to extract each and every frequency component, which might not be possible with the Fourier spectral analysis. Specifically, this study indicates that the decomposed components in EMD of HHT, namely the intrinsic mode function components contain observable, physical information inherent to the original data. Finally, the study illustrates that the HHT-based Hilbert spectra are able to reveal the time-frequency distributions more precisely.