ESTIMATION OF RAIN ATTENUATION AT MICROWAVE BANDS IN NIGERIA

G. A. Akinyemi ¹, J. A. Falade ² and L. B. Kolawole ¹

¹ Department of Physical Sciences, Redeemer’s University, Ede, Nigeria

² Department of Electrical/Electronics Engineering, University of Ilorin, Ilorin, Nigeria

 

The paper is received on June 6, 2018

 

Abstract. The ever-increasing demand on satellite communication systems has resulted in lower frequency bands becoming increasingly congested. The available radio wave frequencies above Ku-band are prone to signal attenuation due to rain. The rain data obtained from the Tropospheric Observatory Data Acquisition Network (TRODAN) of the Nigeria Space Research and Development Agency (NASRDA) located across the geographical zones of Nigeria were used to analyse the rain attenuation from 99.99% to 99.9% availability (i.e., 0.01% to 0.1% unavailability) of time. From the study, at 0.01% of time needed for radio communication system, rain rate values R_0.01 were found to vary from 125 mm/hr to 46.98 mm/hr. The R_0.01 values across the studied locations were subsequently used to estimate rain attenuation using the International Telecommunication Union-Radio (ITU-R) model. Attenuation results show corresponding increase as the path length of the terrestrial links increases. The attenuation due to the horizontally polarized waves is large compared to the attenuation of the vertically polarized waves at all frequencies and in all the locations of the study. It is also evident that availability requirement increases with attenuation. 

Key Words: tropical climate, rain attenuation, rain height, ITU-R model, path length, TRODAN.

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Для цитирования:

G. A. Akinyemi, J. A. Falade and L. B. Kolawole. Estimation of rain attenuation at microwave bands in Nigeria. Журнал радиоэлектроники [электронный журнал]. 2018. №8. Режим доступа: http://jre.cplire.ru/jre/aug18/18/text.pdf
DOI 10.30898/1684-1719.2018.8.18