•   Ilesanmi B. Oluwafemi

  •   Moses O. Olla


Geoclimatic factor variable is one of the most important radio climatic variables in the planning of the radio links in any region. A fade margin that takes into account multipath fading has to be incorporated in the link budget in the design of terrestrial line of sight communication system. This work involves the determination of the refractivity gradient over the first 100 m above ground level in Nigeria and by using the determined refractivity gradient, the geo-climatic factor (K) was calculated for typical links in Nigeria. The Geo-climatic factor (K) for the six major cities representing each geopolitical zone in Nigeria is determined in-order to improve future planning of the radio links in the regions. Measurement of meteorological parameters for five years taken in Ikeja, Lagos (Latitude 6º27´11´´N, Longitude 3º23´44´´E), Enugu (Latitude 6º27´35.8704´´N, Longitude 7º32´56.2164´´E), Kaduna (Latitude 10º31´23´´N, Longitude 7º26´25´´E), Port Harcourt (Latitude 4º47´21´´N, Longitude 6º59´54´´E), Kano (Latitude 12º3’N,Longitude 8º32´N) and Abuja (Latitude 9º10´32´´N Longitude 7º10´50´´E) were employed to estimate the country value of K. The pressure, P(hPa), temperature, T(ºC) and the relative humidity, (%), for the six location used were taken for a period of five years (2011-2015). The value of humidity were converted to water vapour pressure, e(hPa). In processing of the data, the average values of each month collected over a period of five years was used. The monthly data was used to calculate the values of the refractivity at the ground level and at 100 m altitude. From the calculated values of refractivity,the values of the refractivity gradient of heights of 65 m and at 100 m was computed and thereafter the geo-climatic factor (K) was calculated for the six geopolitical region of the country.

Keywords: Geo-climatic factor, Meteorological data, Microwave, Refractivity, Refractivity Gradient


Adediji A.T., Ajewole M.O., Falodun S.E. and Oladosu O.R. (2007). “Radio Refractivity Measurement at 150m altitude on TV tower in Akure, South-West Nigeria” Journal of Engineering and Applied Science, 2007, Nigeria.

Willis, M. Bacon, D, Craig, K. and Rudd R. (2000) “A wide Range Propagation Model,” IEEE Conferences, 2000, pp.1-5.

Yu S. M., Yee Hui L. and Boon C. N. (2009) “Empirical Near Ground Path Loss Modeling in a Forest at VHF and UHF Bands,” IEEE Journals, vol.57, no. 5, pp.1461-1468.

Odedina P.K. and Afullo T.J. (2007), “Use of Spatial Interpolation Technique for the Determination of the Geoclimatic Factor and Fade Depth Calculation for Southern Africa,” Proceedings of IEEE AFRICON conference 2007 ISBN: 0 – 7803 – 8606 – X. IEEE Catalogue number: 04CH37590C, September 26 – 28, 2007, Namibia.

Tjelta T., Oslen R.L. and Martin A.L. (1990), “Systematic Development of New Multivariable Techniques for Predicting the Distribution of Multipath Fading on Terrestrial Microwave Link,” IEEE Transaction on antennas and Propagation, vol.38, pp. 1650-1665.

Olsen R. L. and Tjelta T. (1999), “Worldwide Techniques for predicting the Multipath Fading Distribution on Terrestrial L.O.S. Links: Background gation, Vol. 47, January 1999, pp. 157-170.

Olsen R. L. and Segal B. (1992), “New techniques for predicting the Multipath Fading Distribution on VHF/ UHF/SHF Terrestrial Line-of-Sight Links in Canada Canada Journal of Elec. And Comp. Engineering, Vol. 17, No 1., pp. 11-23.

Martin A., “Key Radio Meteriological Parameters for Designing Line of Sight Links in Multipath Fading Environment,” Martin Communications Pty Ltd, 87 Peters Av, Mulgrave VIC 3170, Australia.

Ezenugu I. A., Ifiok U. Anthony O.and Colman O. A. (2017), “Estimation of Clear-Air Atmospheric Effective Earth Radius (K-Factor) in Calabar”. American Journal of Software Engineering and Applications. vol. 2, No. 3, pp. 35-37, 2017.

Ojo O. L., Ajewole M. O., Adediji A.T. and Ojo J. S. (2015). “Estimation of Clear-Air Fades Depth Due to Radio Climatological Parameters for Microwaves Link Application in Akure, Nigeria”. International Journal of Engineering and Applied Sciences, August. 2015. Vol. 7. No. 03.

Rosemary N. C., Simeon O. and Colman O. A. (2017). “Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria”. Engineering Physics. vol. 2, No.1, 2017, pp. 1-6.

Etokebe I. J., Uko M. C., and Chinwe I. U. (2016), “Determination of Refractivity Gradient and Geoclimatic Factor Using Radiosonde Data and Inverse Distance Weighting Spatial Interpolation for Missing Data”. International Journal of Systems.

Dabideen A.S., Gopichund M., and Afullo T.J. (2005), “Radio Refractivity Distribution and Duct and Fading Occurrence Measurements in Kwazulu-Natal” Transactions of South African Institute of Electrical Engineers (SAIEE), Volume 96, No.2, June 2005, pp121-132.

Valma E., Tmosiunarte M., Tamosiunas S. and Zilinkas M. (2011), “Variation of Radio refractivity with height above ground” Electrical and Electronics Engineering, 2011 No 5(111).

ITU Radio communication Assembly (2015), “Prediction Methods Required for the Design of Terrestrial Line of Sight -R P. 530 16; July 2015.

ITU Radio communication Study Group III (2003): “The Radio Refractive Index: Its formula and Refractivity Data” ITU Radio communication Assembly Document No. ITU-R P.453 -7, 11 July 2003.


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How to Cite
Oluwafemi, I.B. and Olla, M.O. 2021. Estimation of Geoclimatic Factor for Nigeria through Meteorological Data. European Journal of Electrical Engineering and Computer Science. 5, 3 (May 2021), 41-44. DOI:https://doi.org/10.24018/ejece.2021.5.3.191.