An Empirical Analysis of Atmospheric Radio Refractivity Effect on Signal Quality at UHF Band in a Tropical Environment

International Journal of Applied Physics

© 2019 by SSRG - IJAP Journal

Volume 6 Issue 1

Year of Publication : 2019

Authors : Benjamin G. Ayantunji, Francis D. Chizea, Bawa Musa and Adebayo S. Adewumi

10.14445/23500301/IJAP-V6I1P104

How to Cite?

Benjamin G. Ayantunji, Francis D. Chizea, Bawa Musa and Adebayo S. Adewumi, "An Empirical Analysis of Atmospheric Radio Refractivity Effect on Signal Quality at UHF Band in a Tropical Environment," SSRG International Journal of Applied Physics, vol. 6,  no. 1, pp. 7-16, 2019. Crossref, https://doi.org/10.14445/23500301/IJAP-V6I1P104

Abstract:

This study analyzed the impact of atmospheric parameters on UHF signal strength in a tropical environment using Gusau, North West, Nigeria as a case study. The analysis exploited year 2018 meteorological data measured simultaneously with UHF signal strength from instruments situated at Federal University, Gusau (60 78' N, 120 13' E). The refractivity values were computed using ITU-R model. The results show that the average daily variation of refractivity is large due to variations in Humidity, while refractivity reveals seasonal variations with high values in the rainy season (April to October) and low values in the dry season (November to March). Minimum value of 272 N-Units was observed in January. Regression analyses gave UHF signal strength and Relative humidity correlations of 0.633 and 0.85 for December and January, and -0.728 and -0.639 for August and September. Also, the correlation between UHF signal strength and Temperature are -0.597 and -0.890 for December and January, and 0.782 and 0.556 for August and September respectively. Lastly, the correlation between UHF signal strength and radio refractivity are 0.530 and 0.864 for December and January, and 0.311 and 0.364 for August and September. These results indicate that environmental factors have effects on signal quality.

Keywords:

Radio Refractivity, Atmospheric parameters, Ultra High Frequency

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