Enhancement of backscattered intensity in a random medium

When high-frequency radiation traverses twice through random inhomogeneities there arise a number of effects not observed along one-directional propagation paths. To correlate the forward-backward-propagating events, we consider here a paired field measure in which the random information along the propagation path is preserved and apply an approximate analytical solution for the high-frequency propagator of that measure obtained by the multiscale expansion asymptotic procedure. From this function all even statistical moments can be generated. The test of the solution is performed on a canonical backscattering problem based on a point-source–point-scatterer configuration, which justifies its application for construction of the coherence measures of the retroreflected field. We show that the intensity enhancement effect depends on the geometry of the wave front of the incident field.