Equatorial Scintillation Predictions from C/NOFS Planar Langmuir Probe Electron Density Fluctuation Data.

摘要

The main objective of the work was the application of a propagation model based on in-situ measurements ion density irregularities to estimate the scintillation index S4. Initially, the results from a statistical analysis show how the values of the standard deviation DNi of the ion density fluctuations measured by the Planar Langmuir Probe (PLP) onboard the C/NOFS satellite were distributed, as functions of several combinations of several geophysical parameters. Considering the instant and position of detection of a sample of DNi as well as Vdrift, the model determined the instant of time when the sample reached the surface defined by the slant ray path and the intercepted magnetic field lines. Next, DNi was scaled for altitude using the observed average ion density profile. The scaled value of DNi, fixed power spectral density parameters and layer thickness were used to generate a horizontal random phase screen. Finally, a numerical algorithm was used to propagate a wave front to the ground and to estimate S4. The results from the calculations were compared with corresponding scintillation measurements by a 244-MHz Scintillation Network Decision Aid (SCINDA) receiver at Ancon, Peru for validation of a purely space-based scintillation detection, mapping and prediction model.