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Rain constitutes a major limitation to the performance and use of terrestrial and satellite communication systems with operational frequencies greater than 10 GHz. The situation gets further complicated by fast fluctuations in the received signal amplitude due to in homogeneities in atmospheric weather conditions; a phenomenon known as amplitude scintillation. The concurrent evaluation of the two phenomena guarantees a better fade margin determination for the planning of radio communication over any location. This work employs 3 years of in-situ measurement of temperature, humidity, rainfall rate and rainfall amount for the estimation of tropospheric amplitude scintillation and rain specific attenuation over Akure (7.17° N, 5.18° E, 358 m) South West Nigeria. Davis vantage pro weather station at 1-min integration time was used for the measurement and the ITU models for rain specific attenuation (ITU-R P.838-3) and amplitude scintillation (ITU–R 618-13) were employed for the estimation. Time series and statistical analyses of the phenomena show that rain attenuation is the more prominent cause of signal degradation at Ku-band frequencies. Nevertheless, the need to make an extra fade margin allowance of about 0.25 dB due to amplitude scintillation fade subsists to forestall any loss of synchronization on the link. Also, a 3-parameter power-law expression developed for estimating amplitude scintillation fade from rain attenuation performed excellently well, as indicated by average root mean square error (RMSE) and coefficient of determination (R2) values of 0.002151 and 0.8747, respectively.

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Relationship between scintillation intensity (σ χ ) and peak-to-peak amplitude (χ pp) is important for mitigating scintillation effects on any communication link. This study employs linear, logarithmic and polynomial functions for fitting σ χ and χ pp in order to determine the best model for describing the variation of the former with the latter. It also examines the frequency of occurrence of scintillation intensity and the suitable probability density function for characterizing its distribution. Data used spanned 24 months, and were obtained from measurement of EUTELSAT W4/W7 satellite beacons on 12.245 GHz frequency, 1 s integration time and 53° elevation angle, at the Department of Physics, Federal University of Technology, Akure (07°17′N, 005°18′E, 358 m) Nigeria. Results show that logarithmic function performed best in modelling χ pp from σ χ as indicated by high coefficient of determination and minimal root mean sqaure error values. Strong scintillation events (σ χ  > 0.5) were also found to occur less frequently as sample interval increased. Lastly, lognornal, gamma and generalised extreme value (GEV) models were found suitable for describing σ χ distribution.