Scattered intensity of a wave propagating in a discrete random medium.

The present paper aims at a computational scheme to obtain numerical results for the second moment (average intensity) of a wave field propagating in a medium consisting of randomly distributed scatterers, not necessarily simple in shape. A formalism is presented that parallels the diagram method and shows the approximations made in the intensity computation of anisotropic scattering whenever finite size scatterers with a considerable concentration are considered. The back and forth scattering between a pair of scatterers, which has been neglected in the ladder approximation, automatically appears in our formalism taking into account all the multiple scattering between two particles through the pair statistics. Sample numerical results for average intensity scattered by particles are presented and compared to some microwave and optical measurements.