Rain Height Statistics from Spaceborne Radar for Satellite Communication in Malaysia

Abstract

Tropical and equatorial region exhibit significantly higher rainfall compared to the temperate region leading to higher attenuation for satellite communication links. One of the issues in radiowave propagation modeling is the different precipitation structures which play an important role in the estimation of rain fade. However, few results on rain height over Malaysian equatorial stations have been presented so far. To this aim, an investigation on rain height derived from Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) is carried out. In this paper, the bright–band heights (h_BB) have been analyzed to obtain monthly average values of the rain height (h_R). TRMM PR is one of the most powerful instruments able to observe vertical profiles of rainfall. The analysis covers stratiform events around peninsular Malaysia. It is well known that h_BB exists slightly below the 0°C isotherm height (h₀) and this may lead to the estimation of rain height (h_R). The obtained results on rain height are then compared with radiosonde observations and ITU–R Recommendation P.839–3. It is found that the bright–band height (h_BB) appears to vary throughout the year and will mostly lie between 4192 m and 4593 m above mean sea level. The results suggest that by carefully consider the physical information of rain height derived from the various local databases should lead to substantial improvements in the rain attenuation prediction accuracy for equatorial and tropical region.