Ionospheric scintillations on 3.925 GHz signal from Intelsat (701) at low latitude in the South Pacific region

The morphological features of initial ionospheric scintillations on 3.925 GHz beacon signal from geostationary satellite Intelsat (701) at Suva (Lat., 18.08 degrees S, Long., 178.3 degrees E, Geom. Lat., 22.1 degrees S), Fiji, a low latitude station in the South Pacific region have been studied during the period of December 2003 to June 2004. Scintillations were, in general, sparse, of which activity was more pronounced in the daytime. Scintillation occurrence was less in general, showing a peak value of about 2.5% at 09 h LT and a secondary peak of about 2% at around 16 h LT. Scintillations were weak (S-4 index <= 0.25) and occurred mostly in patches of short duration of 2 - 5 min. It is reported here that weak and short duration scintillations with more daytime occurrence are mainly due to (i) the higher frequency beacon signal used, (ii) the recording station being situated off the equatorial ionisation anomaly belt, and (iii) the period of observation falling in the low solar activity phase of the current solar cycle.