Rain attenuation is a major source of impairment to signal propagation at microwave and millimeter wave bands. The procedures for the estimation of rain attenuation values as regard to microwave signals however rely mainly on 1-minute rain rate statistics, particularly those obtained locally from experimental measurement campaigns over a given location. In this paper, we present recent results on 1-minute rain rate statistics required for satellite and terrestrial link designs, as obtained from a 2-year measurement over Akure, Nigeria. The performance of the selected rain rate models; Rice-Holmberg (RH) model, the Kitami model, Moupfouma model and the global ITU rain rate model were tested based on four metrics namely: Prediction error, Root Mean Square Error (RMSE), Spread-Corrected Root Mean Square Error (SC-RMSE) and the Spearman's rank correlation. Results indicate that no single model completely outperforms all others. Interestingly, the RH model is particularly best behaved over the distribution, while the Moupfouma model performs suitably well. Others seem to vary largely from the measured rain rate distribution. Results for the rain rate exceeded for 0.01% of the time agrees with earlier estimates for the cumulative rain rate distribution derived from higher integration-time statistics over this tropical site.

Path loss models are essential in the planning of wireless networks. However, the peculiar ambient characteristics of geographical locations necessitate a wide range of these models to take into consideration the different terrain dielectric, scattering irregularities, and clutter. This study investigates the effects of terrain and clutter on frequency‐dependent path loss models in the very high frequency (VHF) and ultra high frequency (UHF) bands using multi‐transmitter scenarios. Seven transmitters and 15 measurement routes were covered using an Agilent N9342C spectrum analyser. The measured results show that the models' prediction errors (PEs) follow the terrain profile and also that the clutter effects are noticeable along each route with varying degrees of impact. Near constant standard deviation errors (SDEs) were observed across all the models for the specific routes as well as a strong dependency on the terrain profile and clutters along the measurement routes. The UHF and VHF bands have average SDEs of 10.5 and 7.5 dB, respectively. A three‐dimensional digital elevation model (DEM) showing the terrain and PE was also developed. Contour lines were extracted from the advanced spaceborne thermal emission radiometer and global DEM data sets. Visualisation of the terrain profile was achieved in the ArcScene software environment.

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In this work, signal path loss prediction from nine different empirical path loss models were statistically compared with those measured from four television transmitters along five routes that span through urban and rural environments of Osun State, Nigeria. In this respect, results obtained show that both Hata and Davidson prediction models provide best fit prediction consistently along the five measurement routes with 90% to 98% prediction accuracy, Ilorin, CCIR, Cost 231, Ericsson 9999 and ECC-33 show prediction accuracy within the range of 65% to 80% while SUI and Okumura models offer prediction accuracy within the range of 15% to 21%. Generally the results show that Davidson and Hata models have better results in all the five routes examined. SUI and Okumura models show the least performance results.

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