Characterization of Rain Attenuation in 80-200 GHz Radio Links Considering Non-Spherical Raindrops

The use of EHF (30-300 GHz) in terrestrial radio links is one key element in future 5G and beyond 5G technologies. Rain attenuation is the major impairment affecting radio links operating at this band. Due to the lack of experimental measurements for the EHF band, one approach is to estimate rain attenuation by using information about the rain DSD. In previous works, rain attenuation and its variability have been estimated up to 200 GHz by applying the Mie Theory to experimental DSD, considering spherical raindrops. This work goes a step further and provides the derivation of rain attenuation using a non-spherical drop model. To that aim, full-wave electromagnetic software is used to derive the extinction cross section of non- spherical drops excited with horizontal and vertical polarizations. The results show that at such high frequencies the differences between polarizations are not large, but the variability of rain attenuation is not negligible.