Comparing Filtering of Wavelet Decomposed Waves with Moving Averages (Case Study: Vanyar Station in Ajichay Basin)

Document Type : Research Paper

Abstract

In this study the relationship between daily flow decomposed waves of Ajichay river in Vanyar station is investigated using the wavelet and moving average filter. Initially, using wavelet analysis the frequencies distribution of daily flow time series based on scale is decomposed to high and low frequencies and approximate subseries for higher scale are estimated. In the next step moving average filter for decreasing and removing of random noises in daily flow data time series is used. Obtained results represent similar performance of the wavelet analysis and moving average methods in signal smoothing and noise decreasing of Ajichay river daily flow time series for decomposition levels 1 to 10 in wavelet method.Also the quantitative criterion of the correlation coefficient for investigation of the performance similarity of the both methods is used. Results show high correlation between obtained values from the methods used in the study.

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