International Journal of Applied Science and Engineering
Published by Chaoyang University of Technology

Folasade Abiola Semirea,b,*, Rosmiwati Mohd-Mokhtara, Temidayo Victor Omotoshoc, Widad Ismaila, Norizah Mohamada, and J.S. Mandeepd

a School of Electrical and Electronic Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal, Malaysia
b Department of Electronic and Electrical Engineering, Ladoke Akintola University of Technology, P.M.B. Ogbomoso, Oyo State, Nigeria
c Department of Physics, Covenant University, Ota, Ogun State, Nigeria
d Department of Electrical and Electronic Engineering, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia


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ABSTRACT


The conversion of most available hourly rainfall data to 1-minute integration time rain rate statistic is imperative for accurate estimation of attenuation due to rain employed in the design of both terrestrial and earth-to-space microwave systems. 2-year rainfall data collected at Ogbomoso, South-west region of Nigeria, between the periods of 2009 and 2010 was used in the analysis. Result shows that a power law relationship exists between the equiprobable rain rates of two different integration times. The regression coefficients a and b obtained are slightly different from the ITU-R recommendation. The conversion factor obtained at Ogbomoso is lower compared to Ile-Ife, in the South-west region of the country. The disagreement is attributed to the effect of global warming hitting the whole universe most especially the tropical regions. This study also reveals that different conversion factors are required for different locations even within the same climatic region.


Keywords: Rain rate; attenuation; equiprobable rain rate; regression coefficient.


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ARTICLE INFORMATION


Received: 2011-05-11
Revised: 2012-02-06
Accepted: 2012-02-08
Available Online: 2012-09-01


Cite this article:

Semire, F.A., Mohd-Mokhtar, R., Omotosho, T.V., Ismail, W., Mohamad, N., Mandeep, J.S. 2012. Analysis of cumulative distribution function of 2-year rainfall measurements in ogbomoso, Nigeria. International Journal of Applied Science and Engineering, 10, 171–179. https://doi.org/10.6703/IJASE.2012.10(3).171