Abstract

In this paper we analyzed the effects of Radio-climatic secondary variables on signal propagation in Bauchi Metropolis North-east, Nigeria. The primary Radio-climatic data were obtained at Agro-weather station Abubakar Tafawa Balewa University, Bauchi. The primary Radio-climatic data are temperature, pressure and humidity or water vapor pressure, while secondary radio-climatic data includes refractivity (N), refractive index (n) and effective earth’s radius (k-factor). Primary variables collected span for the period of four years (2013-2014). The seasonal variation of the climatic parameters such as temperature, atmospheric pressure and relative humidity may lead to an increase or decrease of the estimated water vapour pressure, refractivity (N), refractive index (n) and effective earth’s radius (k-factor). The result shown as in figure (1) the water vapour pressure is high in the months August and September in 2013. In 2014 Maximum values is obtained in the months of May, August and September. Similarly in the months of June, July, August and September the water vapour pressure is recorded to be very high in (2015 and 2016). Figure (2 and 4) represent the change in Radio refractivity and refractive index and from the plot it was recorded that the maximum is obtained in the months of April and November in (2013 and 2014) while in (2015 and 2016) the maximum values is recorded in the months of May and November. Figure (3) shows that the maximum values of surface earth radius (K – factor) is in the months of January and November while in 2014 it is in the months of January, November and December. In (2015 and 2016) K-factor is maximum in the months of February, April, November and December. The results also, shows that the k-factor values for those months were at the range (0.0018 – 0.0072). This low value of k-factor implies that micro wave can be propagated and transmitted without signal interference in Bauchi Metropolis during both wet and dry season.

Key words: Refractivity, refractive index, k-factor, Bauchi Metropolis.