Improvement of the algorithm for adaptive separation of the vibroseis signal from its harmonics in case of strong additive noise

Abstract

An algorithm for separating a vibroseis signal from its harmonics implies preliminary prediction of harmonics with their subsequent adaptive subtraction from the correlogram. To obtain the adaptation filter estimates, a statistical criterion is used that minimizes the energy of the subtraction result. The amplitudes of the signals in a seismic trace decay due to geometrical spreading, which leads to statistical inhomogeneity in the objective formed. Therefore, an increase in the statistical reliability of estimation should be associated with an increase in signal amplitudes at large recording times. On the other hand, the source records always contain additive noise, and the signal-to-noise ratio decreases at longer times. In order to provide a compromise between the growth of signal amplitudes and maintaining a satisfactory signal-to-noise ratio in the operator adjusting gate, self-tuning weighting functions are included into the objective. A method for modifying the objective is proposed, which enables increased performance of the algorithm.