A general scattering theory

A fundamentally different approach to the problems of electromagnetic wave propagation through a medium containing a distribution of scatterers is presented. The new theory includes the effects of scatterers in the near field of the transmitting and/or receiving antennas, a factor that currently accepted theories do not include. Near-field effects are important especially in the case of satellite microwave communications where the near field of the large ground antennas includes an appreciable fraction or even the whole of the rain path. The theory is based on the Lorentz form of Reciprocity Theorem and may be used to estimate attenuation and depolarization of microwaves through precipitation.