STATISTICS OF THE CUMULATIVE PHASE OF MICROWAVE-RADIATION IN RANDOM-MEDIA

We determine the cumulative phase of microwave radiation transmitted t hrough a sample of randomly positioned polystyrene spheres in measurem ents of the field versus frequency and investigate its statistics, Its probability distribution is Gaussian at all frequencies with a varian ce which is nearly equal to the ensemble average of the phase. These r esults are consistent with our observation that the correlation functi on of the phase derivative with the ensemble average value of the phas e is nearly the same exponential function for diffusing waves over a w ide frequency range. Finally, we indicate ways in which the study of t he cumulative phase can elucidate wave transport in random systems.