The role of particular rain drop size on rain attenuation at 11 GHz

This paper presents the specific attenuation (gamma) at 11 GHz based on measured drop size distribution (DSD). The influence of particular rain drop sizes (diameters) is presented with the conclusion that the drop diameters from 0.771 mm to 5.3 mm are important for DSD and specific rain attenuation (gamma) calculations. DSD for different rain rates are plotted using lognormal model with maximum likelihood estimators. The discrepancy between the measured and modeled values is found to be minimal even though rain drops of diameter less than 0.771 mm are excluded. Over these diameter ranges, the model fits very well to the measured data. The components of specific attenuation at 11 GHz due to individual drop diameters are calculated and drop diameters below 0.771 mm are found to have insignificant contribution to the specific attenuation.