Attenuation/rain-rate relationships on terrestrial microwave links in the frequency range 10--40 GHz

Attenuations of radio transmissions at 10.7, 19.4 and 36.05 GHz by rain on a 7.5 km path have been compared on a statistical basis with attenuations derived from rainfall rates, measured simultaneously along the path, using the empirical relationship β = ?R n , where β is the attenuation coefficient in dB km -1 , R is the rainfall rate in mm h -1 and ? and n are parameters dependent on polarisation and frequency.