Rain attenuation at tropical region-site diversity gain models’s sensitivity

Abstract

Site diversity is one of the effective techniques to avoid rain attenuation especially in tropical region. Therefore, the performance of site diversity scheme is measured using site diversity gain. However, due to lack of measurement data availability, an empirical model to calculate the gain was initiated by Hodge. From this initiative, the model was improvised to suit various data, locally. In this paper, the factor that impacted the total gain that are the frequency, baseline angle, separation distance and elevation angle are discussed. Even though several models were proposed to extend the capability of Hodge’s model, there are still uncertainty in their performance. Therefore, in this paper, model of Hodge, Panagopolous, ITU-R, Semire and X. Yeo were investigated to observe their reactivity towards the four factors. Each model was set default at 20.2GHz, 68.8° of elevation angle, 65° of baseline angle and 42.52km of site separation distance. However, the configuration is not fixed, since each contributor's value is altered to form 16 combinative test lists. Each models percentage of change were recorded and the value of predicted gain by each model was presented. The models sensitiveness towards the contributors were also presented in a table to ease for future references.