Back-ground Noise Decontamination of Experimental Turbulent Time Signals Using Wavelet Transforms

In this paper a novel wavelet based data post-processing method aimed at decontaminating experimental time signals from any coherent contamination is presented. A definition of coherent contamination is given, as well as a presentation of the state-of-the-art decontamination techniques and of their limitations. The new decontamination technique is developed using wavelet transform with the scope of reconstructing a clean signal in the physical domain. The method is successfully tested on wall pressure measurements retrieved from an existing data-base. A discussion is carried out on the achieved results and propositions are done in order to improve the technique in the future.

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