Slant path rain attenuation predictions for Ku and Ka band frequencies from rain cell size distribution over a tropical region in southern India

Abstract

Rain cell size distribution that provides an insight into the modelling of effective slant path length and also imperative for site diversity studies are carried out for a tropical inland location, Tirupati (13.6 N, 76.3 E), India. Rain cell size distribution obtained from 5 years (2013-2015 and 2017-2018) of Parsivel disdrometer measurements is observed to follow the power law. Reduction factor that accounts for the inhomogeneity of the rain along the propagation path for the region of study is modified in terms of the rain cell size distribution of the area. Slant path rain attenuation, a major propagation impediment at Ku and Ka-band links, is then studied using the results from the regional rain characteristics by modifying the CCIR 564-4 report. The attenuation results are compared with Garcia-Lopez, Excell, Bryant, and Ramachandran models while considering the ITU-R P. 618-13 as the standard model.