Rain attenuation measurement on Ku-band satellite TV downlink in small island countries

Analysis of 13-year rain-rate measurements in Fiji shows that the rain exceeded 50 mm/h for 0.01% of a year (R/sub 0.01/), which is significantly lower than those predicted by existing models. Simultaneous measurements of Ku-band attenuation and rain-rate give A/sub 0.01/ and R/sub 0.01/ as 9.7 dB and 54 mm/h, respectively. The ratio of attenuation exceedence for the worst month and yearly (at A=A/sub 0.01/) was 1.8, which is lower than that predicted by the ITU-R study group. The attenuation exceeds the Ku-band link margin for about 15.6 h in a year.