Rainfall Attenuation and Rainfall Rate Measurements in Malaysia Comparison with Prediction Models

Attenuation due to rain is a primary cause of communication impairment on satellite-earth paths, especially above 10GHz. Rainfall is a serious source of attenuation at such a frequency. This paper presents the characteristics of rain distribution in USM based on measured one minute rain rate. For attenuation of rain, predictions models like ITU and VIHT (Variable Isotherm Height Technique) model were used to estimate the effect of rain on Ku band signals. Data of rain attenuation and rainfall rates collected at USM are estimated and compared with the predicted models. The ITU model followed closely to the measured rainfall rate and attenuation data whereas the VIHT models overestimated the measured rainfall rate and attenuation data.