Font Size: a A A

Signal Denoising By Wavelet Transform For Microchip Capillary Electrophoresis

Posted on:2006-09-27Degree:MasterType:Thesis
Country:ChinaCandidate:J H HuangFull Text:PDF
GTID:2168360152475793Subject:Measuring and Testing Technology and Instruments
Abstract/Summary:PDF Full Text Request
As a promising type of miniaturized total analysis system(μTAS), Integrated capillary electrophoresis (ICE) has undergone a rapid progress in recent years. Due to its high throughout ,low sample requirement, ICE has be widely recognized as a powerful tool for chemical analyses. However, when the system of laser-induced fluorescence is used to do some analysis, some background noises are introduced into the signal because of the influence of instrument high voltage,and some other factors. Therefore, to achieve high sensitivity and accuracy, the denoising of capillary electrophoresis signal is necessary before data processing.Wavelet transform(WT) ,emerging as a novel technique, has been shown to be very useful in many fields . Compared with windowed fourier transform, WT adopts a more comfortable windowing technique with variably sized time regions, Wavelets are functions that are both localized in the time and the frequency domains .Because of this property, both time and frequency characteristics of the signal are captured in WT. Therefore, Wavelet transform was applied to noise on removal capillary electrophoresis electropherograms.Several typical wavelet functions, including Daubechies> Coiflets and Symmlets, were evaluated. Four types of determining threshold methods, Sqtwolog,Rigrsure,Heursure,Minimax combined with hard and soft threshold methods are compared. The denoising study on synthetic signals shows that wavelet function Daubecbies 12 with a level decomposition of 5 and the threshold method of Sqtwolog-hard provide the optimum denoising strategy .Using this strategy ,the noise on signals for capillary electrophoresis can be removed adequately. Compared with the Fourier transform denoising method, wavelet transform is an efficient method for noise removal with a better preservation of the shape of peaks.
Keywords/Search Tags:Capillary Ectrophoresis Chip, Electrophoresis Signal, Fourier Transform, Wavelet Denoising
PDF Full Text Request
Related items