Recent developments in tomographic imaging allow the use of GPS satellite data to image the Earth’s ionosphere. Ground-based GPS receivers monitor the Earth’s ionosphere continuously and a comprehensive database of ionospheric measurements suitable for tomographic processing now exists. The tomographic inversion of these GPS data in a three-dimensional time-dependent inversion algorithm can rev...

Variability in the ionosphere during 2020–2021 sudden stratospheric warming (SSW) is investigated using a combination of Constellation Observing System for Meteorology, Ionosphere, and Climate-2 (COSMIC-2) observations Whole Atmosphere Community Climate Model with thermosphere–ionosphere eXtension (WACCM-X) simulations. The unprecedented spatial–temporal sampling low latitude afforded by COSMIC...

Abstract Although ionosphere-weighted GNSS parameter estimation is a popular technique for strengthening estimator performance in the presence of ionospheric delays, no provable rules yet exist that specify needed weighting dependence on circumstances. The goal present contribution therefore to develop and conditions need be satisfied order solution mean squared error (MSE) superior ionosphere-...

Saturn’s magnetic field is remarkably axisymmetric. Its dipole axis is inclined by less than 0.2 with respect to its rotation axis. Early evidence for nonaxisymmetry came from the periodicity of Saturn’s kilometric radio bursts (SKR). Subsequently, percent variations of the SKR period were found to occur on timescales of years. A recent breakthrough has been the direct detection of a nonaxisymm...

[1] The Martian ionosphere’s local total electron content (TEC) and the neutral atmosphere scale height can be derived from radar echoes reflected from the surface of the planet. We report the global distribution of the TEC by analyzing more than 750,000 echoes of the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS). This is the first direct measurement of the TEC of the Mar...

To provide a detailed analysis framework for WAAS accuracy prediction, a new method has been developed which combines GPS geometry simulation with leastsquares covariance analysis. This approach considers all standard ranging errors for each WAAS reference station receiver and user, including satellite clock, SA-induced latency, ephemeris, multipath, receiver noise, troposphere and ionosphere e...

The estimation of Total Electron Content (TEC) in the equatorial ionosphere using GPS presents a number of challenges due to the presence of strong spatio-temporal density gradients and scintillation of the satellite signals caused by F-region irregularities. In this paper we describe a methodology for real-time calibrated TEC estimation in the presence of scintillation and a highly structured ...