Wavelet analysis of short range seismic signals for accurate time of arrival estimation in dispersive environments

This study proposes a wavelet-based method for time of arrival estimation for source localisation purposes. The investigated case concerns seismic signals with poor correlation owing to dispersive propagation and high noise level. The Haar wavelet is selected for its low computational complexity and its good locality in time domain which is essential for the analysis of transient signals. The proposed method requires no a priori knowledge about the spectral characteristics of the signals, because the algorithm defines the optimum scales for the extraction of information by time-domain features as the signal is acquired. The performance of the algorithm is evaluated by computer simulations and application on real data for three different thresholding techniques. The results corroborate the suitability of the proposed method for source localisation applications.