Ionospheric Scintillation Monitoring and Preliminary Statistic Analysis Over Hainan Region

To investigate the equatorial ionospheric scintillation morphology and the relevant physical processes,one GPS ionospheric scintillation monitor was installed at CSSAR Hainan station.The monitor is built on Plessey GPS Builder-2 development system with its software modified to log signal strength from up to 11 channels at a high data rate(50 samples/s).It is suits the high time resolution studies of scintillation spectral and temporal characteristics and also can be used to perform the statistic analysis of scintillation signals.The preliminary analysis results of L-band ionospheric scintillations during Jul.-Dec.2003 show that ionospheric scintillations mainly occur near from sunset to midnight,where the onset and end time are evidently more advanced in Nov.-Dec.than in Jul.-Aug.;the occurrence rate and intensity of ionospheric scintillations are evidently more enhanced in Sept.-Nov.than in other months,and reach their peaks in Oct.;there is the strong randomness for the day-to-day variability of ionospheric scintillations,and the scintillation occurrence reaches their peak during the magnetic quiet days from the end of Sept.to the middle of Oct.near autumnal equinox;the increase of solar and geomagnetic activities generally may limit the occurrence of ionospheric scintillations,especially near autumnal equinox.