Theoretical determination of the effects of multiple scattering by hydrometeors in monopulse systems at millimeter wavelengths

The incoherent radiation incident on a receiving antenna after having been scattered by raindrops can cause some problems in the case of a monopulse system whose directive pattern presents a deep null toward the coherent incoming wave. This null is then filled with incoherent radiation, therefore giving rise to a degradation of the performances of the measuring equipment. In this paper this degradation is theoretically assessed assuming a simplified geometry (a rain cell embedded in stratified rain); the drops are assumed to be of spherical shape, and typical system configurations for the earth station are considered.