Characteristics of ionospheric scintillation measured using GPS receivers onboard the COSMIC satellites

GPS radio occultation and orbit determination receivers onboard six COSMIC satellites have been enabled to measure amplitude scintillation of the L-band signals. The measurements fill large gaps of spatial coverage, particularly over oceans, and significantly augment our capacity of measuring ionospheric irregularities from space. This paper presents an analysis of the scintillation data collected under low solar activity conditions during last few years. The long-term data collection over the globe helps to draw interesting characteristics, which are partially consistent with the known morphology of ionospheric scintillation obtained from ground-based measurements in different regions, but also different in many aspects. The differences are examined in detail to address ionospheric scintillation and irregularities measured from space compared with ground-based measurements. It is attempted in this analysis to derive a guide line to distinguish spaceborne and ground-based measurements of ionospheric scintillation.