Prediction of Rain Attenuation Trend due to Climate Change in Some Locations of Southwestern Nigeria

Abstract

Climate change has become a phenomenon of global concern and it has resultant effect on the variability of radio propagation. In recent times, the issue of climate change has been a global phenomenon having its resultant effect on the variability of radio propagation. High-capacity radio signal fades due to absorption by atmospheric gases and scattering by hydrometeors which limits the link availability. This study is aimed at investigating the effects of climate change trend via rain attenuation along the satellite-earth path over Nigeria’s climate. Rain rates computed by using the compensated function on Semire and Rosmiwati model were utilized to estimate rain attenuations and effective path lengths using ITU-R P.618-13 model on NIGCOMSAT-1R satellite at 0.01% exceedance for selected frequencies within Ku- and K-bands. Linear trend models for annual rain attenuation were also developed. At 0.01% time unavailability, the prediction of rain attenuation on NIGCOMSAT-1R link using ITU-R P.618-13 model ranged from 14 to 28 dB at Ku-band, and rose beyond 40 dB at K-band. This study inferred that trends of rain rate distributions corresponded to the trends in attenuation due to rain and then concluded that the rising trends of yearly signal outage along earth-space path as a result of increasing rainfall intensity was due to climate change in the study area. This outcome can be explored for better communication planning and design in order to provide reliable links in order to satisfy customers’ demand for high quality radio communication.