Seyed Hossein Mohajeri - Formerly graduate student, Dept. of Civil and environmental Engineering, Tarbiat Modares University and PhD student, Dept. of Civil and environmental Engineering, university of Trento
Akbar Safarzade - Assistant Professor, Faculty of Engineering, Mohaghegh Ardebili University
Seyed Ali Akbar Salehi Neyshabouri - Professor, Dept. of Civil and environmental Engineering, Tarbiat Modares University
Masoud Ghodsian - Professor, Dept. of Civil and environmental Engineering, Tarbiat Modares University

Acoustic Doppler velocimeter (ADV) measurements are useful for measurements of mean and turbulent components of fluids in both experimental and field studies. Although ADV has been used commonly for velocity measurements, existence of spikes in the recorded velocity series leads to unreliability of these series. In the present study, four famous despiking algorithms, consist of RC Filter method, Tukey 53H method, acceleration thresholding method and Wavelet thresholding method, were applied to collected data in an straight channel with smooth and rough bed condition. In addition, the wavelet thresholding method as a common and high efficient method was modified. The results show that acceleration thresholding method and modified wavelet method reject spike points and accept valid points. So these methods purify the contaminated series appropriately

Turbulence, Data filtering, Acoustic Doppler velocimeter, Velocity signal processing