Determination of Atmospheric Effective Earth Radius Factor (k-factor) Under Clear Air in Lagos, Nigeria

Iniobong Jackson Etokebe, Kufre M. Udofia, Isaac A. Ezenugu


Due to it cost effectiveness and ease of accessibility, as well as adaptability, radio wave communication at microwave frequencies has earned enormous attention over time. Importantly, secondary radio variables remained very significant in carrying out calculations especially on effective earth radius factor. This study was carried out in Lagos, South West of Nigeria. Three year atmospheric parameters data from Nigerian Meteorological Agency (NIMET) was used. International Telecommunication Union (ITU) recommendation models were applied in determining point refractivity gradient and effective earth radius factor based on radiosonde data obtained from NIMET for Lagos state. The calculated values of effective earth radius factor showed a variation between 1.31 and 1.73 while the point refractivity gradient varied between -398.5034 and -56.42. Also, the yearly average value of dN1 and k-factor for Lagos are -210.111392 and 1.494358 respectively.


earth radius factor; refractivity gradient

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