The ever-increasing demand on satellite communication systems has resulted in lower frequency bands becoming increasingly congested. The available radio wave frequencies above Ku-band are prone to signal attenuation due to rain. The rain data obtained from the Tropospheric Observatory Data Acquisition Network (TRODAN) of the Nigeria Space Research and Development Agency (NASRDA) located across the geographical zones of Nigeria were used to analyse the rain attenuation from 99.99% to 99.9% availability (i.e., 0.01% to 0.1% unavailability) of time. From the study, at 0.01% of time needed for radio communication system, rain rate values R 0.01 were found to vary from 125 mm/hr to 46.98 mm/hr. The R 0.01 values across the studied locations were subsequently used to estimate rain attenuation using the International Telecommunication Union-Radio (ITU-R) model. Attenuation results show corresponding increase as the path length of the terrestrial links increases. The attenuation due to the horizontally polarized waves is large compared to the attenuation of the vertically polarized waves at all frequencies and in all the locations of the study. It is also evident that availability requirement increases with attenuation.

An investigation on the diurnal and seasonal variability of ionospheric Total Electron Content (TEC) over Nigeria is carried out in this study using Global Positioning System (GPS) observable. Nigeria coordinates fall within the trough of equatorial ionization anomaly region of African sector. The TEC data used were obtained from the ground-based GPS receiver stations of the Nigerian GNSS network of stations (NIGNET). The stations with their respective geomagnetic latitudes are Abuja (−1.64º), Yola (−1.32º), Zaria (−0.13º) and Kebbi (0.72º). The results of the diurnal analysis of the relative variability index (VD) revealed higher nighttime values than daytime values. The diurnal variation of VD also showed two conspicuous peaks: the post-midnight and the post-sunset. The diurnal-seasonal variation does not reveal any consistent pattern (no particular season leads the others throughout). On the average, considering all the seasons together maximum TEC variability occurred in Zaria (62%) and least in Yola (54%). Seasonally, maximum VD was recorded during March equinox and the least was recorded during December equinox.

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