Phase variance of narrow-band acoustic signals on near-surface paths

Abstract

Results of the analysis of the “instantaneous” phase of narrow-band acoustic signals during their propagation on short near-surface paths under the action of the wind field are presented. The division of the phase into the deterministic, quasi-deterministic (“local”), and random (“turbulent”) components is applied. Histograms of the turbulent component of the phase and result of approximating the histograms by the normal law of the probability distribution are considered. An empirical formula for the relation between the phase variance at different frequencies and variance of the wind velocity on the sound propagation path is derived and compared with theoretical formulas.