Seasonal Analysis of Real-Time Derived and ITU-R Modeled Surface Radio Refractivity in a Tropical Region Using a Low-Cost Developed Device

Authors

  • Abdulgafar Babatunde Giwa

    Department of Physics, Bamidele Olumilua University of Education Science and Technology, Ikere-Ekiti, Ikere-Ekiti P.M.B. 250, Nigeria
  • Joseph Sunday Ojo

    Department of Physics, The Federal University of Technology Akure, Akure P.M.B. 704, Nigeria
  • Opeyemi Vincent Omole

    Department of Physics, Bamidele Olumilua University of Education Science and Technology, Ikere-Ekiti, Ikere-Ekiti P.M.B. 250, Nigeria
  • Waheed Ademola Toriola

    Department of Physics and Electronics, University of Ilesa, Ilesa P.M.B. 5089, Nigeria

DOI:

https://doi.org/10.30564/jeis.v8i1.13026
Received: 21 January 2026 | Revised: 30 March 2026 | Accepted: 17 April 2026 | Published Online: 24 April 2026

Abstract

This study investigates seasonal and diurnal variations of surface radio refractivity in a tropical region by comparing real-time derived values from a low-cost automated Global System for Mobile Communication Signal Strength and Radio Climatological (GSM-RC) monitoring device with those modeled by ITU-R P.453-13. The GSM-RC device, installed at 3-m height, provided real-time, in-situ measurements of temperature, pressure, and humidity. Refractivity was derived in real-time from this high-resolution data and compared against model outputs across four months representing distinct climatic phases: January (dry season), April (commencement of rainy season), July (intense rainy season), and October (fading season). Results show a strong correlation between datasets, with seasonal atmospheric dynamics driving clear patterns. The dry season exhibited large diurnal fluctuations due to low humidity and high solar radiation, while the intense rainy season showed minimal variability from persistently high humidity and reduced temperature gradients. Transitional months displayed moderate instability. Although the ITU-R model provided reliable smoothed approximations, real-time derived data proved superior at capturing transient fluctuations, particularly during atmospheric instability. These findings underscore the value of locally-sourced real-time data for capturing dynamic refractivity behaviour and highlight opportunities to enhance climatological propagation models. By linking observed patterns to West African monsoon phases, this work provides valuable insight for telecommunications system design, weather prediction, and regional atmospheric monitoring in tropical environments.

Keywords:

Atmospheric Monitoring; In-Situ Measurement; ITU-R P.453-13; Radio Refractivity; Seasonal Variation; Tropical Region

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How to Cite

Giwa, A. B., Ojo, J. S., Omole, O. V., & Toriola, W. A. (2026). Seasonal Analysis of Real-Time Derived and ITU-R Modeled Surface Radio Refractivity in a Tropical Region Using a Low-Cost Developed Device. Journal of Electronic & Information Systems, 8(1), 80–96. https://doi.org/10.30564/jeis.v8i1.13026

Issue

Vol. 8 , Iss. 1 (April 2026): In Progress

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ARTICLE

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Copyright © 2026 A. B. Giwa , J. S. Ojo, O. V. Omole, W. A. Toriola

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This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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