Scattering properties of Pruppacher-and-Pitter form raindrops and cross polarization due to rain: Calculations at 11, 13, 19.3, and 34.8 GHz


  • Tomohiro Oguchi


Forward-scattering amplitudes of raindrops are computed at 11, 13, 19.3, and 34.8 GHz for a real raindrop shape given by Pruppacher and Pitter, assuming plane waves at normal incidence to the drop axis. Horizontal and vertical polarizations are considered in the incident field. These forward-scattering amplitudes are then used to estimate cross polarization by rain. Cross-polarization factors are calculated for two kinds of raindrop canting angle distributions: gaussian distributions and a photographically measured distribution. The results show that the scatter of the drop canting angles reduces the cross polarization considerably as compared with that for equioriented raindrops.