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The ionosphere shows regular changes such as daily, 27 days, seasonal, semi-annual, annual, and 11 years. These changes can be modeled and their effects largely determined. However, in addition to regular changes, irregular changes occur in the ...

Ionospheric indices give information about ionospheric perturbations, which may cause absorption, diffraction, refraction, and scattering of radio signals, including those from global navigation satellite systems (GNSS). Therefore, there may be a ...

Co-seismic ionospheric disturbances (CIDs) can help understand the coupled dynamics of earthquake-atmospheric coupling geophysical processes. On September 19, 2022, an earthquake occurred at UTC = 18:05:08 near the Pacific Coast of Mexico as the ...

The ionosphere is an atmospheric region in which a large number of charged particles interact. Therefore, the production and loss mechanisms in this region play an important role in the modeling and interpretation of the ionosphere. In this study, ...

Our investigation aims to answer if it is possible to detect plasma bubbles using single-frequency measurements of the Global Navigation Satellite System (GNSS). In this regard, we show a methodology based on a regional model to calibrate GNSS ...

Global navigation satellite system (GNSS) signals are significantly affected by the ionosphere. An efficient way to assess the ionospheric effects on GNSS signals is by retrieving the vertical total electron content (VTEC). Here, we propose ...

The insufficient number of low-elevation observations is a limitation of the three-dimensional ionospheric computer tomography (CT) based on the global navigation satellite system (GNSS). To solve this problem, accurate prior information on the ...

The advancements in computational resources and Artificial Intelligence (AI) technological tools can predict Global Ionospheric Maps (GIMs). The prediction of GIMs certainly helps the Global Navigation Satellite System (GNSS) users with ...

Ionospheric scintillation affects the positioning, navigation and timing services of the Global Navigation Satellite System (GNSS), calling for an urgent need for scintillation monitoring on a global scale. To monitor the ionospheric scintillation ...

The global TEC empirical model established with the TEC grid data of IGS as the background has poor prediction accuracy in marine areas, and its ability to describe some ionospheric anomalies is insufficient. In response to the above two problems, ...

Second order statistical moments of the temporal spectrum of scattered ordinary and extraordinary electromagnetic waves in the equatorial ionosphere are considered analytically and numerically using geometrical optics approximation and random ...

Ionospheric delay is one of the major error sources in precise navigation and space geodesy. A substantial effort has been made to model the global ionosphere variation in real time, and the current bottleneck for the ionosphere modeling is the ...

The global navigation satellite system (GNSS) measurements to determine ionospheric total electron content (TEC) are mainly derived from expensive geodetic-grade receivers, which are not conducive to high-density placement. In this work, we ...

In Satellite-Based Augmentation Systems (SBASs), e.g., the US Wide-Area Augmentation System (WAAS), the planar method and the kriging method based on the thin-shell model have been used to estimate the ionospheric grid delay (IGD). Generally, the ...

The widely used GNSS correction services for high precision positioning take advantage of accurate real-time TEC forecasting based on vertical total electron content (VTEC) maps. The methods for modeling and forecasting are mainly based on overly ...

The vertical total electron content (VTEC) is one of the key quantities to describe variations of the ionosphere and can be provided to users to correct the ionospheric disturbances for GNSS (Global Navigation Satellite System) positioning. The ...

The data from low-flying satellites play both an independent and an additional role in the study of the ionosphere. In this paper, data from the Swarm satellite were used to assess the state of the ionosphere during the disturbance period of April 19-21,...

We propose a new method for spatio-temporal modeling of the ionospheric total electron content (TEC) at severe solar activity periods using a support vector machine (SVM). Using the observations from 37 GPS stations of the Iranian permanent GPS ...

Ionosphere Associate Analysis Centers (IAACs) of the International GNSS Service (IGS) independently produce global ionosphere maps (GIMs) of the total electron content (TEC). The GIMs are based on different modeling techniques, resulting in ...

Low-earth-orbit (LEO) spacecraft formation flying (SFF) simulated on the Virginia Tech Formation Flying Testbed (VTFFTB) demonstrated the feasibility of detecting simplified ionospheric electron density (Ne) structures (i.e., one-dimensional ...