Rain attenuation at 40 GHz for terrestrial link in Malaysia

This paper presents the study on the rain attenuation at 40 GHz via terrestrial link in Malaysia. Malaysia is situated in the tropical region and known to experience a very heavy rainfall annually. Consequently, this heavy rainfall has high impact on the millimeter wave propagating signals. In this study, rainfall data at Cyberjaya were collected using rain gauge, and then they were analyzed to get the rainfall rate in term of probability of the time exceedance. Five different prediction models were used to estimate the rain attenuation values; ITU-R 530-15 models, ITU-R 530-13 models, revised Moupfouma´s model, revised Silva Mello´s model and Lin´s model. Among these five models, ITU-R 530-15 model gave the closest estimated value to the measured rain attenuation at 38 GHz. By applying this model with the acquired rainfall rate of 130 mm/h, it gave the estimated attenuation value of 22.64 dB within 0.3 km propagating path at frequency of 40 GHz.