Filtering detecting signal of rockbolt with harmonic wavelet

Abstract

Harmonic wavelets not only possess the traditional advantages of a wavelet function, they also have other merits such as clear expressions, more flexible time-frequency divisions, a simple transformation algorithm, a finer box-like frequency spectrum and others. Given the frequency distribution characteristics of the nondestructive testing signals from a rockbolt support system and based on the discrete harmonic wavelet transformation theory, we have effectively abstracted signals from frequency ranges concerned by removing useless high and low frequency signals from the testing signals of the rockbolt support system and obtained filtered signals with a reconstruction algorithm of harmonic wavelets. Finally, we applied the harmonic wavelet transformation in filtering analog signals and measured response signals of rockbolts. The results indicate that harmonic wavelets also have excellent filtering characteristics.