Attenuation and phase shift of the electromagnetic waves due to moist snow

Abstract

Based on the point matching technique, the attenuation and the phase shift of the electromagnetic waves due to moist snow are computed. The analysis is restricted to the forward scattering direction from oblate spheroidal moist snow. Numerical results are obtained for two orthogonal polarizations of the incident wave. The calculations are made for various microwave frequencies, between 6 and 100 GHz, and also for different precipitation rates, between 0.5 and 3 mm/hr. The effect of the frequency and the precipitation rate on the attenuation and the phase shift is examined. It is found that at a fixed value of the precipitation rate, the attenuation of both polarizations increases and the phase shift decreases with increasing frequency. It is also observed that at a fixed frequency, the attenuation of both polarizations increases and the phase shift decreases with increasing precipitation rate. The differential attenuation and the differential phase are found to follow the same trend as the attenuations and the phase simultaneously for frequencies greater than 20 GHz and are negligible for frequencies below 20 GHz.