Modifications de propagation dues aux retards aléatoires

Abstract
Acoustic waves can undergo random delays because of propagation atmosphere turbulence. If the emitted wave is monochromatic with a frequency [MATH], the wave received at a point can be modelized in the form [MATH] where A(t) is the propagation delay. It is shown that, in this model, the received monochromatic wave has to be accompanied by a noise the power spectrum of which will depend on propagation delay variation speed. More particularly, the case where A(t) is a gaussian process is examined and it is shown that this hypothesis is particularly appropriate to account for gas and liquid losses.