CATEGORIZATION OF MEASURED RAINFALL RATES AND ESTIMATION OF THEIR IMPACT ON RADIO WAVE PROPAGATION AT HIGHER FREQUENCY BAND (12.5 GHz) IN WUKARI, TARABA STATE, NIGERIA

Abstract

This study presents the categorization of measured rainfall rate and estimation of their impact on radio wave propagating at 12.5GHz. Rain rate at one minute interval were measured using Davis Vantage Vue weather station which is equipped with an integrated sensor suite (ISS) and weather link data logger. The rainfall rates were measured and categorized into Drizzle (≤5mm/hr), Widespread (>5≤25mm/hr), Shower (>25≤50mm/hr) and Thunder (>50mm/hr). The results obtained revealed that the impact of drizzle (≤5mm/hr) on the radio signal is not significant regardless the duration of rainfall. The results also revealed that severe signal losses recorded under shower (>25≤50mm/hr) and thunderstorm (>50mm/hr) were due to a greater value of BER (≥10^-9) which affected and reduced the level of the received signal as such limiting the performance of the propagated signal under rain. This is because, for a satisfactory performance of radio link under rain, the measured BER should be less than 10^-9as recommended by ITU-R.  The results further revealed that widespread (>5≤25mm/hr) that prevailed for a longer period also causes severe signal losses. This is to say that lower rain rate of about 25mm/hr that prevailed for a very long time have significant effect on the propagated signal