A study of C band equatorial scintillation in the Asian sector

Ionosphere scintillation data at 4 GHz received in Hong Kong are used to study the statistics of scintillating signals. The data were taken during the last solar maximum (1979-1980) and covered two ionospheric locations, POR (123°E, 20°N) and IOR (108°E, 20°N). The study includes two parts. First, the cumulative distribution functions of the signal are generated from the data base and compared with theoretical distributions. Signal statistics such as the decibel levels of maximum peak, 5% peak, 95% fade and maximum fade are recorded and compared to the scintillation index S4. Empirical relations between S4 and these decibel levels are obtained through statistical analysis. It will be shown that simple linear relations exist between S4 and peak/fade decibel levels. These relations were compared with the results obtained from the “third peak” method for determining the SI index. The second part of the study involved a statistical investigation of the variations of the decorrelation interval of the signal and the roll-off slope of the power spectrum. Diurnal and seasonal variations are investigated. Geophysical interpretation of the results are presented.