Author : G.Madhavilatha 1
Date of Publication :6th March 2017
Abstract: Hilbert-Huang transform (HHT) is a new technique for processing and analyzing the non-linear and non-stationary signal, however it still has some drawbacks. This method has inadequacy estimating both the maximum and also the minimum values of the signals at both ends of the border, or envelopes. Traditional HHT produce boundary error in empirical mode decomposition (EMD) method. to overcome this disadvantage, this paper proposes an improved empirical mode decomposition algorithm for processing complex signal. Our work mainly focuses on two aspects. On one hand, we develop a method to get the extreme points of observation interval boundary by introducing the linear extrapolation into EMD. This method is simple however effective in suppressing the error-prone effects of decomposition. On the other hand, a completely unique envelope fitting technique is proposed for processing complex signal, that employs a method of non uniform rational B-splines curve. This technique will accurately measure the average value of instantaneous signal, which helps to achieve the accurate signal decomposition. In this paper new technique was implemented on nonlinear and non stationary radar signal, which not only eliminated end effect but also observed SNR improvement compared with HHT.
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