A simplified approach to the evaluation of EMW propagationcharacteristics in rain and melting snow

Electromagnetic propagation characteristics in rain and melting snow are calculated by treating these media as artificial dielectrics. Computed values of attenuation and phase shift in rain, obtained by this approach, are compared with those derived by using Mie scattering theory over a frequency range of 1-1000 GHz and for rain rates up to 100 mm/h. Very close agreement is generally obtained over these entire ranges. Melting snow is treated in the same manner, where comparison is possible these results tend to agree well with the available, but rather limited, published data. Attenuation and phase shift are calculated as a function of the degree of melting of the snow particles. Subject to assumptions relating the degree of melting to depth in the melting layer, average values of attenuation and phase shift are computed as functions of frequency. The attenuation values compare well with those derived from an empirical formula over the range of its validity