Frequency dependence of slant-path amplitude scintillations

The Letter reports scintillation measurements using the beacons of the Olympus satellite at 12.5, 20 and 30GHz. Based on a period of 30 months, the frequency dependence of amplitude scintillations has been investigated. In the Letter, complete monthly distributions of short-term signal variances, which could be characterised by a single parameter, were taken into account. Results have been compared with those of an earlier investigation based on a one-year subset of the data base. The latter considered only variances which were exceeded for low time percentages. Furthermore, results have been compared with the existing ITU-R scheme and with experimental results found in the literature.