Radio Refractivity Study in Akure-Owo Digital Microwave Link in South Western Nigeria
This work is a study of radio refractivity in Akure-Owo Digital Microwave Link in South Western Nigeria. Meteorological data of air temperature, atmospheric pressure, relative humidity, and water vapour pressure were measured between January and December 2006 at the observatory centre of the Nigerian meteorological agency (NIMET) situated at Akure Airport. The meteorological data collected were computed to obtain the refractivity, refractivity gradient and earth radius factor. The results of the study show that the refractivity gradient was greater than zero and vary slightly throughout the months of the year 2006. The highest value of refractivity gradient was in April and lowest value in September, the effective earth radius factor was observed to be less than one which implies that there is sub-refraction in the link. Sub refraction is a situation in which the radio signal beam is refracted upwards in the link thereby resulting in microwave link loss.