Simulation of radiometric and attenuation measurements along Earth-satellite links in the 10-to 50-GHz band through horizontally finite convective rain cells

An iterative solution is illustrated of the three-dimensional radiative tra nsfer equation for a horizontally finite and vertically inhomogeneous preci pitating cloud. The method is applied to modeling a convective rain cell of cylindrical shape, characterized by spherical raindrops having a negative- exponential drop size distribution. The realistic model also takes into acc ount the presence of a cloud and an ice layer above the rain cell itself. T he simulated brightness temperature, the mean radiative temperature, and th e path attenuation are evaluated in a three-dimensional geometry from a sur face observation point in order to simulate a ground-based station with a b eacon receiver and a multichannel radiometer. Numerical results are shown t o illustrate the potential of the proposed model for different sets of freq uency channels, observation geometries, cloud sizes and types, and precipit ation intensities. After generating a large data set by varying the relevan t rain cell parameters, regression analysis is applied to derive a statisti cal estimation of the total path attenuation from surface rain rate and gro und-based radiometric measurements together with the frequency scaling fact ors for cumuliform clouds in the 10- to 50-GHz band.