Measurement of Ionospheric Total Electron Content Using Single‐Frequency Geostationary Satellite Observations

Abstract

The ionized upper portion of the atmosphere, the ionosphere, affects radio signals traveling between satellites and the ground. This degrades the performance of satellite navigation, surveillance, and communication systems. Techniques to measure and mitigate ionospheric effects and in particular to measure the total electron content (TEC) are therefore required. TEC is usually determined by analyzing the differential delay experienced by dual‐frequency signals. Here we demonstrate a technique which enables TEC to be derived using single‐frequency signals passing between geostationary satellites and terrestrial Global Positioning System (GPS) receivers. Geostationary satellites offer the key advantage that the raypaths are not moving and hence are easier to interpret than standard GPS TEC. Daily TEC time series are derived for three ground receivers from Europe over the year 2015. The technique is validated by correlation analysis both between pairs of ground receiver observations and between ground receivers and independent ionosonde observations. The correlation between pairs of receivers over a year shows good agreement. Good agreement was also seen between the TEC time series and ionosonde data, suggesting the technique is reliable and routinely produces realistic ionospheric information. The technique is not suitable for use on every GPS receiver type because drift in derived TEC values was observed for profiles calculated using receivers without links to highly stable clocks. The demonstrated technique has the potential to become a routine method to derive TEC, helping to map the ionosphere in real time and to mitigate ionospheric effects on radio systems.

GNSS-Based Non-Negative Absolute Ionosphere Total Electron Content, its Spatial Gradients, Time Derivatives and Differential Code Biases: Bounded-Variable Least-Squares and Taylor Series

“…For geostationary Earth orbit (GEO) satellites it is difficult to estimate DCB (or similar error in single frequency data) from (1), because S in Equation (1) is a constant. The corresponding error can be regarded as a TEC offset [ 45 ]. However, GEO satellites’ DCB could be estimated along with DCB of medium Earth orbit (MEO) satellites [ 46 ].…”

Single point positioning with vertical total electron content estimation based on single-epoch data

“…The basic concepts of the GPS signals delay were briefly considered by Golubkov et al (2018a, b) and Kuverova et al (2019). To specify a suitable magnitude of delayed GPS signal along an appropriate path between receiver and satellite, a proportional quantity such as total electron content (TEC) has to be involved and defined as the linear integral of the density of the particles alongside the ray path (Cooper et al, 2019). The TEC unit is equal to 10 16 electrons per square metre (in the cross-section of 1 m 2 ) (Ciraolo, 2005).…”

Advantages of Geostationary Satellites for Ionospheric Anomaly Studies: Ionospheric Plasma Depletion Following a Rocket Launch

“…For example, recent studies have shown the advantages of using BeiDou geostationary (GEO) satellites to study ionospheric longitudinal gradients [21] and for precise monitoring of the ionosphere [22,23] without contaminating the solution with the effect of the satellite motions. A recent technique that allows daily relative TEC time series to be derived using single-frequency signal transmitted from a geostationary satellite is presented in [24]. In addition, Kunitsyn et al [25] investigated the application of Wide Area Augmentation System (WAAS)-GEO L1/L5 signals for ionospheric remote sensing and showed a good agreement between the continuous GEO TEC observations and ionosonde measurements.…”