Summary: | The accurate prediction of a signal’s attenuation is essential for the development of reliable, modern, mobile radio-communication networks. In this study, the accuracies of four propagation models in diverse terrains and environments were analyzed using field measurements along a comprehensive test route. We evaluated the ability of the models—Egli, Okumura, Hata–Davidson, and Longley–Rice—to predict signal propagation in the Very-High-Frequency (VHF) and Ultra-High-Frequency (UHF) bands. Based on a meticulous comparison, we present valuable insights into the strengths and limitations of these models, enhancing coverage-prediction methodologies for evolving mobile radio networks. The Egli model, despite its simplicity, introduces significant inaccuracies due to its assumptions and a lack of consideration for the terrain. The Okumura model, which is widely used in urban areas, requires careful correction selection, while the Hata–Davidson model improves upon the former’s weaknesses. The Longley–Rice model excels in flexibility and accuracy, especially in the VHF bands, using topographical data, though it can overestimate the attenuation in shadowed areas. The study concluded that no single model was universally accurate, as each model has its strengths and limitations. It highlights the need for informed model selection based on the terrain’s characteristics and specific requirements. The results will be useful to network planners, helping them to design efficient, mobile communication networks with reliable coverage and optimal spectrum utilization. The Longley–Rice model emerged as particularly powerful, offering detailed predictions across diverse environments.
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