Attenuation and phase rotation of radio waves due to rain: Calculations at 19.3 and 34.8 GHz


  • Tomohiro Oguchi


Computations are made of the forward- and back-scattering intensities of oblate spheroidal raindrops at 19.3 and 34.8 GHz, assuming plane waves at normal incidence to the drop axis. Two kinds of polarization are considered in the incident field: one is parallel to drop axis; the other is perpendicular. Numerical values of these basic scattering intensities are listed in tables. Forward-scattering intensities are then used for determining the effective propagation constants of rain-filled space. From these propagation constants, attenuations and phase rotations for parallel and perpendicular polarizations are computed for several rain rates. One significant conclusion is that the difference between phase rotations in the two polarizations at 19.3 GHz becomes very large as the rain rate increases, whereas that at 34.8 GHz is bounded in a very small range throughout all possible rain rates.