Predicting Combined Rain and Wet Snow Attenuation on Terrestrial Links

Radio links are used in all parts of the world, and must operate reliably in local climatic conditions. Attenuation due to rain has been extensively studied, but the additional loss due to wet snow has received less attention. Until recently there has been no wet-snow prediction model in general use. This paper reviews a recently developed prediction method for the attenuation due to combined rain and wet snow, proposes an extension to account for path inclination, and gives practical evidence of the excess attenuation caused by wet snow. The proposed model is based on data compiled by the International Telecommunication Union (ITU), and is applicable anywhere in the world. The basis of the predication method has recently been adopted in an ITU recommendation.