Study on plasma blob to result in radio signal scintillations in low latitude ionosphere

摘要

It is well known that the ionosphere has significant influences on the radio wave propagation, for example, can result in radio signal scintillation. In general, the scintillations in the low latitude ionosphere are considered as signatures of equatorial plasma bubbles (depletions). However, some authors considered that the scintillations may also be associated with plasma blobs (enhancements), but it needs further observation to be confirmed. We performed a case study on concurrent observation of ionospheric plasma blob with in-situ measurements by satellite ROCSAT-1 and of radio signal amplitude scintillations with GPS receiver at low latitude Hainan station (19.5°N, 109.1°E, Mag 8.9°N) on March 8, 2004. The ionospheric plasma blob in the F-layer measured in-situ had extend distance of about 375 km along the orbit. The ion density inside the blobs was very high and severely disturbed. The concurrently observed GPS signal amplitude scintillations were with S₄