Relevant bibliographies by topics / Ionospheric modeling

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Ionospheric modeling'

Author: Grafiati
Published: 6 September 2023

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Journal articles on the topic "Ionospheric modeling"

1

Wang, Yafeng, Hu Wang, Yamin Dang, Hongyang Ma, Changhui Xu, Qiang Yang, Yingying Ren, and Shushan Fang. "BDS and Galileo: Global Ionosphere Modeling and the Comparison to GPS and GLONASS." Remote Sensing 14, no. 21 (October 31, 2022): 5479. http://dx.doi.org/10.3390/rs14215479.

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The ionospheric delay is one of the important error sources in the Global Navigation Satellite System (GNSS) data processing. With the rapid construction and development of GNSS, the abundant satellite resources have brought new opportunities for ionospheric monitoring. To further investigate the performances and abilities of Galileo and BDS in ionosphere modeling, we study the ionosphere modeling based on the 15th order spherical harmonic function, and 364 stations around the world are selected for global ionospheric modeling of GPS, GLONASS, Galileo and BDS systems under ionospheric quiet and active conditions, respectively. The results show that the average biases of the ionospheric models built by GPS, GLONASS and Galileo are relatively small, which are within 2 Total Electron Content Unit (TECU) as compared to the Center for Orbit Determination in Europe (CODE) global ionospheric map (GIM), while the average biases of the models built by BDS are between 6 and 8 TECU during the ionospheric quiet and active days, respectively. In addition, in order to analyze the modeling performances before and after using BDS geostationary earth orbit (GEO) satellites, BDS is divided into two groups, in which one group contains medium earth orbit (MEO), inclined geosynchronous orbit (IGSO) and GEO satellites; and the other group contains only MEO and IGSO satellites. The results show that the influence of GEO satellites on ionospheric modeling is less than 1 TECU. Due to the distribution of the stations, the 0-value region in the ionospheric model is mainly distributed in the mid and high-latitude regions of the southern hemisphere. Since the ionospheric parameters are lumped with the Differential Code Bias (DCB), we also estimate the DCB parameters and analyze their performances. The DCB estimated in ionosphere modeling shows strong stability, with the average biases of GPS, GLONASS, Galileo and BDS under 0.25 ns, 0.25 ns, 0.2 ns and 0.42 ns, respectively. We also estimate other DCB types of the four GNSS systems. The results show that the DCB is stable and shows consistency with Chinese Academy of Sciences (CAS) DCB products.
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Ким, Антон, Anton Kim, Елена Романова, Elena Romanova, Галина Котович, Galina Kotovich, Сергей Пономарчук, and Sergey Ponomarchuk. "Modeling z-shaped disturbance along the Pedersen ray of oblique sounding ionogram using adaptation of IRI to experimental data." Solar-Terrestrial Physics 2, no. 4 (February 2, 2017): 55–69. http://dx.doi.org/10.12737/24273.

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We present the results of numerical modeling of a traveling ionospheric disturbance that causes z-shaped bends at the Pedersen ray of oblique incidence ionograms. The results of trajectory synthesis of oblique incidence ionograms are given for the ionosphere, taking into account the traveling ionospheric disturbance. In the work, we use the International Reference Ionosphere, adapted to experimental data, and the Global Model of the Ionosphere and Plasmasphere.
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Su, Ke, and Shuanggen Jin. "Three Dual-Frequency Precise Point Positioning Models for the Ionospheric Modeling and Satellite Pseudorange Observable-Specific Signal Bias Estimation." Remote Sensing 13, no. 24 (December 15, 2021): 5093. http://dx.doi.org/10.3390/rs13245093.

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Global Navigation Satellite System (GNSS) Precise Point Positioning (PPP) enables the estimation the ionospheric vertical total electron content (VTEC) as well as the by-product of the satellite Pseudorange observable-specific signal bias (OSB). The single-frequency PPP models, with the ionosphere-float and ionosphere-free approaches in ionospheric studies, have recently been discussed by the authors. However, the multi-frequency observations can improve the performances of the ionospheric research compared with the single-frequency approaches. This paper presents three dual-frequency PPP approaches using the BeiDou Navigation Satellite System (BDS) B1I/B3I observations to investigate ionospheric activities. Datasets collected from the globally distributed stations are used to evaluate the performance of the ionospheric modeling with the ionospheric single- and multi-layer mapping functions (MFs), respectively. The characteristics of the estimated ionospheric VTEC and BDS satellite pseudorange OSB are both analyzed. The results indicated that the three dual-frequency PPP models could all be applied to the ionospheric studies, among which the dual-frequency ionosphere-float PPP model exhibits the best performance. The three dual-frequency PPP models all possess the capacity for ionospheric applications in the GNSS community.
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Håkansson, Martin. "Nadir-Dependent GNSS Code Biases and Their Effect on 2D and 3D Ionosphere Modeling." Remote Sensing 12, no. 6 (March 19, 2020): 995. http://dx.doi.org/10.3390/rs12060995.

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Recent publications have shown that group delay variations are present in the code observables of the BeiDou system, as well as to a lesser degree in the code observables of the global positioning system (GPS). These variations could potentially affect precise point positioning, integer ambiguity resolution by the Hatch–Melbourne–Wübbena linear combination, and total electron content estimation for ionosphere modeling from global navigation satellite system (GNSS) observations. The latter is an important characteristic of the ionosphere and a prerequisite in some applications of precise positioning. By analyzing the residuals from total electron content estimation, the existence of group delay variations was confirmed by a method independent of the methods previously used. It also provides knowledge of the effects of group delay variations on ionosphere modeling. These biases were confirmed both for two-dimensional ionosphere modeling by the thin shell model, as well as for three-dimensional ionosphere modeling using tomographic inversion. BeiDou group delay variations were prominent and consistent in the residuals for both the two-dimensional and three-dimensional case of ionosphere modeling, while GPS group delay variations were smaller and could not be confirmed due to the accuracy limitations of the ionospheric models. Group delay variations were, to a larger extent, absorbed by the ionospheric model when three-dimensional ionospheric tomography was performed in comparison with two-dimensional modeling.
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Jee, Geonhwa. "Fundamentals of Numerical Modeling of the Mid-latitude Ionosphere." Journal of Astronomy and Space Sciences 40, no. 1 (March 2023): 11–18. http://dx.doi.org/10.5140/jass.2023.40.1.11.

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The ionosphere is one of the key components of the near-Earth’s space environment and has a practical consequence to the human society as a nearest region of the space environment to the Earth. Therefore, it becomes essential to specify and forecast the state of the ionosphere using both the observations and numerical models. In particular, numerical modeling of the ionosphere is a prerequisite not only for better understanding of the physical processes occurring within the ionosphere but also for the specification and forecast of the space weather. There are several approaches for modeling the ionosphere, including data-based empirical modeling, physics-based theoretical modeling and data assimilation modeling. In this review, these three types of the ionospheric model are briefly introduced with recently available models. And among those approaches, fundamental aspects of the physics-based ionospheric model will be described using the basic equations governing the mid-latitude ionosphere. Then a numerical solution of the equations will be discussed with required boundary conditions.
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Романова, Елена, Elena Romanova, Галина Котович, Galina Kotovich, Сергей Пономарчук, Sergey Ponomarchuk, Антон Ким, and Anton Kim. "Modeling z-shaped disturbance along the Pedersen ray of oblique sounding ionogram using adaptation of IRI to experimental data." Solnechno-Zemnaya Fizika 2, no. 4 (December 20, 2016): 43–53. http://dx.doi.org/10.12737/21815.

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We present the results of numerical modeling of a traveling ionospheric disturbance that causes z-shaped bends at the Pedersen ray of oblique incidence ionograms. The results of trajectory synthesis of oblique incidence ionograms are given for the ionosphere, taking into account the traveling ionospheric disturbance. In the work, we use the International Reference Ionosphere, adapted to experimental data, and the Model of Ionosphere and Plasmasphere.
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Onohara, A. N., I. S. Batista, and H. Takahashi. "The ultra-fast Kelvin waves in the equatorial ionosphere: observations and modeling." Annales Geophysicae 31, no. 2 (February 7, 2013): 209–15. http://dx.doi.org/10.5194/angeo-31-209-2013.

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Abstract. The main purpose of this study is to investigate the vertical coupling between the mesosphere and lower thermosphere (MLT) region and the ionosphere through ultra-fast Kelvin (UFK) waves in the equatorial atmosphere. The effect of UFK waves on the ionospheric parameters was estimated using an ionospheric model which calculates electrostatic potential in the E-region and solves coupled electrodynamics of the equatorial ionosphere in the E- and F-regions. The UFK wave was observed in the South American equatorial region during February–March 2005. The MLT wind data obtained by meteor radar at São João do Cariri (7.5° S, 37.5° W) and ionospheric F-layer bottom height (h'F) observed by ionosonde at Fortaleza (3.9° S; 38.4° W) were used in order to calculate the wave characteristics and amplitude of oscillation. The simulation results showed that the combined electrodynamical effect of tides and UFK waves in the MLT region could explain the oscillations observed in the ionospheric parameters.
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DABBAKUTI, J. R. K. Kumar, D. Venkata RATNAM, and Surendra SUNDA. "MODELLING OF IONOSPHERIC TIME DELAYS BASED ON ADJUSTED SPHERICAL HARMONIC ANALYSIS." Aviation 20, no. 1 (April 11, 2016): 1–7. http://dx.doi.org/10.3846/16487788.2016.1162197.

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The ionosphere is the region of the upper atmosphere and the study of the upper atmosphere has a significant role in monitoring, modeling and forecasting for satellite based navigation services. As India lies in a low latitude region, a more careful approach has to be taken to characterize the ionosphere due to the irregularities and equatorial anomaly conditions. In order to study the ionospheric temporal variations, a regional ionospheric model based on the Adjusted Spherical Harmonic Analysis (ASHA) is implemented. The results indicate that the ASHA model is one of the contenders for estimating ionospheric delays well for GNSS augmentation systems.
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Danzer, J., S. B. Healy, and I. D. Culverwell. "A simulation study with a new residual ionospheric error model for GPS radio occultation climatologies." Atmospheric Measurement Techniques 8, no. 8 (August 21, 2015): 3395–404. http://dx.doi.org/10.5194/amt-8-3395-2015.

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Abstract. In this study, a new model was explored which corrects for higher order ionospheric residuals in Global Positioning System (GPS) radio occultation (RO) data. Recently, the theoretical basis of this new "residual ionospheric error model" has been outlined (Healy and Culverwell, 2015). The method was tested in simulations with a one-dimensional model ionosphere. The proposed new model for computing the residual ionospheric error is the product of two factors, one of which expresses its variation from profile to profile and from time to time in terms of measurable quantities (the L1 and L2 bending angles), while the other describes the weak variation with altitude. A simple integral expression for the residual error (Vorob’ev and Krasil’nikova, 1994) has been shown to be in excellent numerical agreement with the exact value, for a simple Chapman layer ionosphere. In this case, the "altitudinal" element of the residual error varies (decreases) by no more than about 25 % between ~10 and ~100 km for physically reasonable Chapman layer parameters. For other simple model ionospheres the integral can be evaluated exactly, and results are in reasonable agreement with those of an equivalent Chapman layer. In this follow-up study the overall objective was to explore the validity of the new residual ionospheric error model for more detailed simulations, based on modeling through a complex three-dimensional ionosphere. The simulation study was set up, simulating day and night GPS RO profiles for the period of a solar cycle with and without an ionosphere. The residual ionospheric error was studied, the new error model was tested, and temporal and spatial variations of the model were investigated. The model performed well in the simulation study, capturing the temporal variability of the ionospheric residual. Although it was not possible, due to high noise of the simulated bending-angle profiles at mid- to high latitudes, to perform a thorough latitudinal investigation of the performance of the model, first positive and encouraging results were found at low latitudes. Furthermore, first application tests of the model on the data showed a reduction in temperature level of the ionospheric residual at 40 km from about −2.2 to −0.2 K.
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Wang, Jin, Guanwen Huang, Peiyuan Zhou, Yuanxi Yang, Qin Zhang, and Yang Gao. "Advantages of Uncombined Precise Point Positioning with Fixed Ambiguity Resolution for Slant Total Electron Content (STEC) and Differential Code Bias (DCB) Estimation." Remote Sensing 12, no. 2 (January 17, 2020): 304. http://dx.doi.org/10.3390/rs12020304.

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The determination of slant total electron content (STEC) between satellites and receivers is the first step for establishing an ionospheric model. However, the leveling errors, caused by the smoothed ambiguity solutions in the carrier-to-code leveling (CCL) method, degrade the performance of ionosphere modeling and differential code bias (DCB) estimation. To reduce the leveling errors, an uncombined and undifferenced precise point positioning (PPP) method with ambiguity resolution (AR) was used to directly extract the STEC. Firstly, the ionospheric observables were estimated with CCL, PPP float-ambiguity solutions, and PPP fixed-ambiguity solutions, respectively, to analyze the short-term temporal variation of receiver DCB in zero or short baselines. Then, the global ionospheric map (GIM) was modeled using three types of ionospheric observables based on the single-layer model (SLM) assumption. Compared with the CCL method, the slight variations of receiver DCBs can be obviously distinguished using high precise ionospheric observables, with a 58.4% and 71.2% improvement of the standard deviation (STD) for PPP float-ambiguity and fixed-ambiguity solutions, respectively. For ionosphere modeling, the 24.7% and 27.9% improvements for posteriori residuals were achieved for PPP float-ambiguity and fixed-ambiguity solutions, compared to the CCL method. The corresponding improvement for residuals of the vertical total electron contents (VTECs) compared with the Center for Orbit Determination in Europe (CODE) final GIM products in global accuracy was 9.2% and 13.7% for PPP float-ambiguity and fixed-ambiguity solutions, respectively. The results show that the PPP fixed-ambiguity solution is the best one for the GIM product modeling and satellite DCBs estimation.
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Dissertations / Theses on the topic "Ionospheric modeling"

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Arora, Balwinder Singh Amrit Singh. "Ionospheric modeling for low frequency radioastronomy." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/56529.

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The research presented in this thesis aims to develop ionospheric corrections for calibration of future low frequency radio interferometers. GNSS data from ground stations close to the MRO were used to produce a model of the ionosphere. Comparisons of this model with ionospheric parameters derived from the MWA observations show good agreement. The installation of new GNSS stations in the vicinity of MRO would allow ionospheric modelling with higher spatial resolution.
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Moraes, Alison de Oliveira. "Advances in statistical modeling of ionospheric scintillation." Instituto Tecnológico de Aeronáutica, 2013. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2240.

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Ionospheric scintillation is a phenomenon that occurs daily, especially around the equatorial region, during the summer solstice after the sunset, affecting radio signals that propagate through the ionosphere. Depending on the temporal and spatial situation, ionospheric scintillation can represent a problem in the availability and precision of the Global Navigation Satellite Systems (GNSS). This work is concerned with the statistical modeling and evaluation of the impact of amplitude scintillation on the performance of Global Positioning System (GPS) receivers. In this work the use of ?-? model is proposed to represent the scintillation phenomenon affecting GPS receiver performance. The use of ?-? is also extended for second order statistics. Such a model is compared to a set of experimental data obtained in São José dos Campos, near the peak of the Equatorial Anomaly, during high solar fux conditions, between the months of December 2001 and January 2002. The results obtained with the proposed ?-? model fitted quite well with the experimental data and performed better than two of the widely used models, namely Nakagami-m and Rice. The proposed model requires the estimation of two parameters, instead of a single one used by the models of Nakagami-m and Rice. To facilitate its use, for the situations in which no set of experimental data is available, this work presents parameterized equations for calculating the two parameters required by the ?-? model. Based upon the fact that the proposed model performs better than the one proposed by Nakagami-m, the present investigation derives a model to estimate the carrier and code tracking loop errors on GPS receivers. Such a model not only performed better than Nakagami';s, but also is valid for a wider range of scintillation.
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Ismail, Atikah. "Fourier spectral methods for numerical modeling of ionospheric processes." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-03142009-040454/.

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Brosie, Kayla Nicole. "Ionospheric Scintillation Prediction, Modeling, and Observation Techniques for the August 2017 Solar Eclipse." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78710.

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A full solar eclipse is going to be visible from a range of states in the contiguous United States on August 21, 2017. Since the atmosphere of the Earth is charged by the sun, the blocking of the sunlight by the moon may cause short term changes to the atmosphere, such as density and temperature alterations. There are many ways to measure these changes, one of these being ionospheric scintillation. Ionospheric scintillation is rapid amplitude and phase fluctuations of signals passing through the ionosphere caused by electron density irregularities in the ionosphere. At mid-latitudes, scintillation is not as common of an occurrence as it is in equatorial or high-altitude regions. One of the theories that this paper looks into is the possibility of the solar eclipse producing an instability in the ionosphere that will cause the mid-latitude region to experience scintillations that would not normally be present. Instabilities that could produce scintillation are reviewed and altered further to model similar conditions to those that might occur during the solar eclipse. From this, the satellites that are being used are discuses, as is hardware and software tools were developed to record the scintillation measurements. Although this work was accomplished before the eclipse occurred, measurement tools were developed and verified along with generating a model that predicted if the solar eclipse will produce an instability large enough to cause scintillation for high frequency satellite downlinks.
Master of Science
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Deshpande, Kshitija Bharat. "Investigation of High Latitude Ionospheric Irregularities utilizing Modeling and GPS Observations." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/49507.

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Complex magnetosphere-ionosphere coupling mechanisms result in high latitude irregularities that are difficult to characterize. Until recently, the polar and auroral irregularities remained largely unexplored. Inadequate infrastructures to deploy and maintain advanced dual frequency Global Navigation Satellite System (GNSS) receivers at high latitudes, especially in the Southern hemisphere, makes such an investigation a formidable task. Additionally, the complicated geometry of the magnetic field lines in these regions pose challenges in designing global scintillation models. This dissertation takes some steps towards bridging these gaps while advancing the state-of-the-art high latitude irregularity studies. In the first part of this dissertation, we briefly describe the Autonomous Adaptive Low-Power Instrument Platforms (AAL-PIP) experimental setup. These space science instrument platforms are being deployed in remote locations in Antarctica, improving the coverage of GNSS data availability. We explain in detail the method developed for analyzing high rate (typically 50 Hz) data from a novel dual-frequency Global Positioning System (GPS) receiver called Connected Autonomous Space Environment Sensor (CASES). We also report first observations from CASES at high latitudes. From this study, we established that CASES can be reliably used as a science grade GPS scintillation monitor. Following this, a novel three dimensional (3D) electromagnetic (EM) wave propagation model called "Satellite-beacon Ionospheric-scintillation Global Model of the upper Atmosphere" (SIGMA) was developed to simulate GNSS scintillations on ground. GPS scintillation simulations of significantly high fidelity are now possible with this model. While the model is global, it is the first such model which accounts for the complicated geometry of magnetic field lines at high latitudes. Using SIGMA, a sensitivity study is presented to understand the effect of geographical, propagation and irregularity parameters on the phase scintillations. This allows us to reduce the dimensionality of the design space while solving the inverse problem described next. In the final part, we utilize the tools developed for GPS measurement analysis and SIGMA to characterize the high latitude irregularities. We propose an inverse modeling technique to derive irregularity parameters by comparing the high rate (50 Hz) GNSS observations to the modeled outputs. We consider interhemispheric high latitude datasets for this investigation. We also implement SIGMA for analyzing a substorm event observed by AAL-PIP stations. One of the unique contributions of this research is to demonstrate that such an inverse modeling technique can form a basis in the investigation of the ionospheric irregularities. Moreover, availability of ample auxiliary data from multi-instrument observations can assist in this quest of understanding the physics of high latitude irregularities and their generation mechanisms.
Ph. D.
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Lyu, Haixia. "Contributions to ionospheric modeling with GNSS in mapping function, tomography and polar electron." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/670334.

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This dissertation focuses on determining the vertical electron content distribution in low and high vertical resolution from ground-based and LEO on board GNSS data and improving the knowledge of ionosphere climatology in northern mid-latitude and polar regions. The novelty is summarized in the following four aspects: The first contribution is to propose a new ionospheric mapping function concept - Barcelona Ionospheric Mapping Function (BIMF), in order to improve STEC (Slant Total Electron Content) conversion accuracy from any given VTEC (Vertical Total Electron Content) model. BIMF is based on the climatic modeling of the VTEC fraction in the second layer - µ2, which is the byproduct of UQRG generated by UPC. The first implementation of BIMF is BIMF-nml for the northern mid-latitudes, where the latitudinal variation of µ2 is neglected. µ2 is modeled as function of date and local time. From the user’s perspective, BIMF is the linear combination of µ2 and the standard ionospheric mapping function, and only needs 41 constant coefficients, making BIMF achieve the simplicity for application. The good performance has been demonstrated in the dSTEC assessment for different IGSGIMs: UQRG, CODG and JPLG. The second contribution is to confirm the capability of UQRG GIMs to detect representative ionospheric features in polar regions through six case studies, including TOI (Tongue of Ionization), trough, flux transfer event, theta-aurora, ionospheric convection patterns and storm enhanced density. The long-term VTEC and µ2 data provide valuable databases for studying the morphology and climatology of polar ionospheric phenomena. The unsupervised clustering results of normalized VTEC distribution show that TOI and polar cap patches exhibit an annual dependence, i.e. most TOI and patches occurring in the North Hemisphere winter and the South Hemisphere summer. The third contribution is to propose a hybrid method - AVHIRO (the Abel-VaryChap Hybrid modeling from topside Incomplete RO data), to solve an ill-posed rank-deficient problem in the Abel electron density retrieval. This work is driven by the future EUMETSAT Polar System 2nd Generation, which provides truncated ionospheric RO data, only below impact heights of 500 km, in order to guarantee a full data gathering of the neutral part. AVHIRO takes advantage of one Linear Vary-Chap model, where the scale height increases linearly with altitude above the F2 layer peak, and uses Powell search to solve the full electron densities, ambiguity term, and four parameters of the Vary-Chap model simultaneously, taking into account the nonlinear interactions between the unknown parameters. The fourth contribution is to take advantage of the geometry brought by combining DORIS, ground-based Galileo, ground-based, LEO-POD and vessel-based GPS data and ingest the multi-source dual-frequency carrier phase measurements into the tomographic model to improve the GIM VTEC estimation precision. The impact of adding each type of measurements, which are Galileo data, vessel-based GPS data, DORIS and LEO-POD GPS data, to ground-based GPS data on GIM product is examined according to two complementing evaluation criteria, JASON-3 VTEC comparison and GPS dSTEC test. This study proves the expected better GIM performance by new data ingestion into tomographic model, which is a successful step forward from conception to initial experimental validation.
electrones en resolución vertical baja y alta a partir de medidas GNSS terrestres y a bordo de satélites de órbita baja (LEO), además de utilizar medidas GNSS desde buques y medidas DORIS, además de mejorar el conocimiento de la climatología de la ionosfera en las regiones polares y en latitudes medias del hemisferio norte. Las contribuciones se pueden resumir en los siguientes cuatro aspectos: La primera contribución consiste en proponer un nuevo concepto de función de mapeo ionosférico: la función de mapeo ionosférico de Barcelona (BIMF), con el fin de mejorar la precisión de conversión de STEC (contenido total de electrones inclinado) a partir de cualquier modelo de VTEC (contenido total de electrones vertical). BIMF se basa en el modelado climático de la fracción VTEC en la segunda capa - μ2, que es el subproducto de UQRG generado por UPC. La primera implementación de BIMF es BIMF-nml para las latitudes medias del hemisferio norte. μ2 se modela en función del dia y la hora local. Desde la perspectiva del usuario, BIMF es la combinación lineal de μ2 y la función de mapeo ionosférico estándar, y solo necesita 41 coeficientes constantes, lo que hace que BIMF sea facilmente aplicable. Su buen comportamiento se demostró en la evaluación dSTEC para diferentes IGS GIM: UQRG, CODG y JPLG. La segunda contribución se centró en confirmar la capacidad de los GIM UQRG para detectar características ionosféricas representativas en regiones polares a través de seis estudios de casos, que incluyen lenguas de ionización (TOI), depresión de ionización en forma de canal, sucesos de transferencia de flujo, theta-aurora, patrones de convección ionosférica y densidad aumentada durante tormentas geomagnéticas. Los datos a largo plazo de VTEC y μ2 proporcionan valiosas bases de datos para estudiar la morfología y climatología de los fenómenos ionosféricos polares. Los resultados de agrupamiento no supervisados de la distribución normalizada de VTEC muestran que los TOI y los parches en los casquetes polares exhiben una dependencia anual, es decir, la mayoría de los TOI y parches ocurren en el invierno del Hemisferio Norte y el verano del Hemisferio Sur. La tercera contribución ha consistido en proponer un método híbrido: AVHIRO (el modelo híbrido Abel-VaryChap a partir de datos de RO incompletos en la parte superior), para resolver un problema de rango deficiente en la recuperación de la densidad electrónica con el modelo de Abel. Este trabajo está motivado por el futuro sistema polar EUMETSAT de segunda generación, que proporciona datos truncados de RO ionosférica, sólo por debajo de las alturas de impacto de 500 km, con el fin de garantizar una recopilación completa de medidas de la parte neutra. AVHIRO aprovecha un modelo Linear Vary-Chap, donde la altura de la escala aumenta linealmente con la altitud por encima del pico de la capa F2, y utiliza la búsqueda Powell para resolver las densidades completas de electrones, el término de ambig ¨ uedad y cuatro parámetros del modelo Vary-Chap simultáneamente, teniendo en cuenta las interacciones no lineales entre los parámetros desconocidos. La cuarta contribución es aprovechar la geometría aportada por la combinación de datos GPS DORIS, Galileo en tierra, LEO-POD y en barco, e incorporar las mediciones de la fase de la portadora de doble frecuencia de múltiples fuentes en el modelo tomográfico para mejorar la precisión de estimación de GIM VTEC. El impacto de agregar cada tipo de mediciones, que son datos de Galileo, datos de GPS basados en embarcaciones, datos de GPS DORIS y LEO-POD, a datos de GPS terrestres en productos GIM se examina de acuerdo con dos criterios de evaluación complementarios, comparación con VTEC[JASON-3] y con dSTEC[GPS]. Este estudio demuestra el mejor rendimiento esperado de GIM por la nueva ingesta de datos en el modelo tomográfico, que es un exitoso paso adelante desde la concepción hasta la validación experimental inicial.
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Aghakarimi, Armin. "Local Modeling Of The Ionospheric Vertical Total Electron Content (vtec) Using Particle Filter." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614867/index.pdf.

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ABSTRACT LOCAL MODELING OF THE IONOSPHERIC VERTICAL TOTAL ELECTRON CONTENT (VTEC) USING PARTICLE FILTER Aghakarimi, Armin M.Sc., Department of Geodetic and Geographic Information Technologies Supervisor: Prof. Dr. Mahmut Onur Karslioglu September 2012, 98 pages Ionosphere modeling is an important field of current studies because of its influences on the propagation of the electromagnetic signals. Among the various methods of obtaining ionospheric information, Global Positioning System (GPS) is the most prominent one because of extensive stations distributed all over the world. There are several studies in the literature related to the modeling of the ionosphere in terms of Total Electron Content (TEC). However, most of these studies investigate the ionosphere in the global and regional scales. On the other hand, complex dynamic of the ionosphere requires further studies in the local structure of the TEC distribution. In this work, Particle filter has been used for the investigation of local character of the ionosphere VTEC. Besides, standard Kalman filter as an effective method for optimal state estimation is applied to the same data sets to compare the corresponding results with results of Particle filter. The comparison shows that Particle filter indicates better performance than the standard Kalman filter especially during the geomagnetic storm. MATLAB©
R2011 software has been used for programing all processes and algorithms of the study.
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8

Kindervatter, Tim. "Survey of Ionospheric Propagation Effects and Modeling Techniques for Mitigation of GPS Error." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1515106508878179.

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Pinkepank, James Alan. "The applicability of neural networks to ionospheric modeling in support of relocatable over-the-horizon radar." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA286114.

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Eltrass, Ahmed Said Hassan Ahmed. "The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/51804.

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The mid-latitude ionosphere is more complicated than previously thought, as it includes many different scales of wave-like structures. Recent studies reveal that the mid-latitude ionospheric irregularities are less understood due to lack of models and observations that can explain the characteristics of the observed wave structures. Since temperature and density gradients are a persistent feature in the mid-latitude ionosphere near the plasmapause, the drift mode growth rate at short wavelengths may explain the mid-latitude decameter-scale ionospheric irregularities observed by the Super Dual Auroral Radar Network (SuperDARN). In the context of this dissertation, we focus on investigating the plasma waves responsible for the mid-latitude ionospheric irregularities and studying their influence on Global Positioning System (GPS) scintillations. First, the physical mechanism of the Temperature Gradient Instability (TGI), which is a strong candidate for producing mid-latitude irregularities, is proposed. The electro- static dispersion relation for TGI is extended into the kinetic regime appropriate for High- Frequency (HF) radars by including Landau damping, finite gyro-radius effects, and tem- perature anisotropy. The kinetic dispersion relation of the Gradient Drift Instability (GDI) including finite ion gyro-radius effects is also solved to consider decameter-scale waves gen- eration. The TGI and GDI calculations are obtained over a broad set of parameter regimes to underscore limitations in fluid theory for short wavelengths and to provide perspective on the experimental observations. Joint measurements by the Millstone Hill Incoherent Scatter Radar (ISR) and the Su- perDARN HF radar located at Wallops Island, Virginia have identified the presence of decameter-scale electron density irregularities that have been proposed to be responsible for low-velocity Sub-Auroral Ionospheric Scatter (SAIS) observed by SuperDARN radars. In order to investigate the mechanism responsible for the growth of these irregularities, a time series for the growth rate of both TGI and GDI is developed. The time series is computed for both perpendicular and meridional density and temperature gradients. The growth rate comparison shows that the TGI is the most likely generation mechanism for the observed quiet-time irregularities and the GDI is expected to play a relatively minor role in irregular- ity generation. This is the first experimental confirmation that mid-latitude decameter-scale ionospheric irregularities are produced by the TGI or by turbulent cascade from primary irregularity structures produced from this instability. The quiet- and disturbed-times plasma wave irregularities are compared by investigating co-located experimental observations by the Blackstone SuperDARN radar and the Millstone Hill ISR under various sets of geomagnetic conditions. The radar observations in conjunction with growth rate calculations suggest that the TGI in association with the GDI or a cascade product from them may cause the observations of disturbed-time sub-auroral ionospheric irregularities. Following this, the nonlinear evolution of the TGI is investigated utilizing gyro-kinetic Particle-In-Cell (PIC) simulation techniques with Monte Carlo collisions for the first time. The purpose of this investigation is to identify the mechanism responsible for the nonlinear saturation as well as the associated anomalous transport. The simulation results indicate that the nonlinear E x B convection (trapping) of the electrons is the dominant TGI sat- uration mechanism. The spatial power spectra of the electrostatic potential and density fluctuations associated with the TGI are also computed and the results show wave cascad- ing of TGI from kilometer scales into the decameter-scale regime of the radar observations. This suggests that the observed mid-latitude decameter-scale ionospheric irregularities may be produced directly by the TGI or by turbulent cascade from primary longer-wavelength irregularity structures produced from this instability. Finally, the potential impact of the mid-latitude ionospheric irregularities on GPS signals is investigated utilizing modeling and observations. The recorded GPS data at mid-latitude stations are analyzed to study the amplitude and phase fluctuations of the GPS signals and to investigate the spectral index variations due to ionospheric irregularities. The GPS measurements show weak to moderate scintillations of GPS L1 signals in the presence of ionospheric irregularities during disturbed geomagnetic conditions. The GPS spectral indices are calculated and found to be in the same range of the numerical simulations of TGI and GDI. Both simulation results and GPS spectral analysis are consistent with previous in-situ satellite measurements during disturbed periods, showing that the spectral index of mid- latitude density irregularities are of the order 2. The scintillation results along with radar observations suggest that the observed decameter-scale irregularities that cause SuperDARN backscatter, co-exist with kilometer-scale irregularities that cause L-band scintillations. The alignment between the experimental, theoretical, and computational results of this study suggests that turbulent cascade processes of TGI and GDI may cause the observations of GPS scintillations that occur under disturbed conditions of the mid-latitude F-region ionosphere. The TGI and GDI wave cascading lends further support to the belief that the E-region may be responsible for shorting out the F-region TGI and GDI electric fields before and around sunset and ultimately leading to irregularity suppression.
Ph. D.
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Books on the topic "Ionospheric modeling"

1

N, Korenkov Jurij, ed. Ionospheric modeling. Basel: Birkhäuser, 1988.

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United States. National Aeronautics and Space Administration., ed. Semi-annual report on NASA grant NAGW5-1097: MIAMI, modeling of the magnetosphere-ionosphere-atmosphere system, 1 November 1996 to 31 March 1997. [Washington, DC: National Aeronautics and Space Administration, 1997.

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Memarzadeh, Y. Ionospheric modeling for precise GNSS applications. Delft: Nederlandse Commissie voor Geodesie = Netherlands Geodetic Commission, 2009.

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Vogler, Lewis E. A new approach to HF channel modeling and simulation. Boulder, Colo: U.S. Dept. of Commerce, National Telecommunications and Information Administration, 1988.

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A, Hoffmeyer J., and United States. National Telecommunications and Information Administration., eds. A new approach to HF channel modeling and simulation. Boulder, Colo: U.S. Dept. of Commerce, National Telecommunications and Information Administration, 1988.

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Vogler, Lewis E. A new approach to HF channel modeling and simulation. Boulder, Colo: U.S. Dept. of Commerce, National Telecommunications and Information Administration, 1988.

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Vogler, Lewis E. A new approach to HF channel modeling and simulation. [Boulder, CO]: U.S. Dept. of Commerce, National Telecommunications and Information Administration, 1988.

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Vogler, Lewis E. A new approach to HF channel modeling and simulation. Boulder, Colo: U.S. Dept. of Commerce, National Telecommunications and Information Administration, 1988.

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Korenkov, Jurij N., ed. Ionospheric Modelling. Basel: Birkhäuser Basel, 1988. http://dx.doi.org/10.1007/978-3-0348-6532-6.

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R, Cander L., Kouris S, Zolesi B, and European Geophysical Society, eds. Ionospheric variability, modelling and predictions. Oxford: Pergamon, 2001.

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Book chapters on the topic "Ionospheric modeling"

1

Richmond, A. D., and A. Maute. "Ionospheric Electrodynamics Modeling." In Modeling the Ionosphere-Thermosphere System, 57–71. Chichester, UK: John Wiley & Sons, Ltd, 2014. http://dx.doi.org/10.1002/9781118704417.ch6.

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Hysell, D. L., H. C. Aveiro, and J. L. Chau. "Ionospheric Irregularities." In Modeling the Ionosphere-Thermosphere System, 217–40. Chichester, UK: John Wiley & Sons, Ltd, 2014. http://dx.doi.org/10.1002/9781118704417.ch18.

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Mingalev, V. S., V. N. Krivilev, M. L. Yevlashina, and G. I. Mingaleva. "Numerical Modeling of the High-Latitude F-Layer Anomalies." In Ionospheric Modelling, 323–34. Basel: Birkhäuser Basel, 1988. http://dx.doi.org/10.1007/978-3-0348-6532-6_6.

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Saenko, Yu S., N. S. Natsvalyan, and N. Yu Tepenitsyna. "Modeling of the Planetary Structure of the Ionosphere and the Protonosphere Coupling." In Ionospheric Modelling, 335–52. Basel: Birkhäuser Basel, 1988. http://dx.doi.org/10.1007/978-3-0348-6532-6_7.

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Nigussie, Melessew, Baylie Damtie, Endawoke Yizengaw, and Sandro M. Radicella. "Modeling the East African Ionosphere." In Ionospheric Space Weather, 207–24. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781118929216.ch17.

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Kamide, Yohsuke, and Wolfgang Baumjohann. "Modeling of Ionospheric Electrodynamics." In Magnetosphere-Ionosphere Coupling, 79–121. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-50062-6_4.

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Yau, A. W., W. K. Peterson, and E. G. Shelley. "Quantitative parametrization of energetic ionospheric ion outflow." In Modeling Magnetospheric Plasma, 211–17. Washington, D. C.: American Geophysical Union, 1988. http://dx.doi.org/10.1029/gm044p0211.

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Winglee, R. M., R. D. Sydora, and M. Ashour-Abdalla. "Alfvén ion-cyclotron heating of ionospheric O+ Ions." In Modeling Magnetospheric Plasma, 205–9. Washington, D. C.: American Geophysical Union, 1988. http://dx.doi.org/10.1029/gm044p0205.

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Fuller-Rowell, T. J., A. D. Richmond, and N. Maruyama. "Global modeling of storm-time thermospheric dynamics and electrodynamics." In Midlatitude Ionospheric Dynamics and Disturbances, 187–200. Washington, D. C.: American Geophysical Union, 2008. http://dx.doi.org/10.1029/181gm18.

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Haider, S. A. "Solar Flux for Ionospheric Modeling of Mars." In Aeronomy of Mars, 89–96. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-3138-5_11.

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Conference papers on the topic "Ionospheric modeling"

1

Schunk, R., and J. Sojka. "Advances in ionospheric modeling." In 37th Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1999. http://dx.doi.org/10.2514/6.1999-628.

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Schunk, R., L. Scherliess, and J. Sojika. "Ionospheric specification and forecast modeling." In 39th Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2001. http://dx.doi.org/10.2514/6.2001-236.

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Ji, Yuanfa, Yu Liu, Xiyan Sun, Ning Guo, Songke Zhao, and Kamarul Hawari Ghazali. "Modeling and Correction Analysis of Regional Ionospheric Modeling." In 2022 IEEE 6th Information Technology and Mechatronics Engineering Conference (ITOEC). IEEE, 2022. http://dx.doi.org/10.1109/itoec53115.2022.9734319.

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Chao-Lun Mai and Jean-Fu Kiang. "Modeling of tsinami-induced ionospheric irregularities." In 2008 IEEE Antennas and Propagation Society International Symposium and USNC/URSI National Radio Science Meeting. IEEE, 2008. http://dx.doi.org/10.1109/aps.2008.4619019.

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Meng, Xing, Attila Komjathy, Olga P. Verkhoglyadova, Giorgio Savastano, Mattia Crespi, and Michela Ravanelli. "Modeling the Near-field Ionospheric Disturbances During Earthquakes." In ION 2019 Pacific PNT Meeting. Institute of Navigation, 2019. http://dx.doi.org/10.33012/2019.16844.

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Scales, W. A. "Recent advances in modeling ionospheric stimulated electromagnetic emissions." In 2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS). IEEE, 2021. http://dx.doi.org/10.23919/ursigass51995.2021.9560621.

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Moore, Robert C., and Anthony J. Erdman. "Nonlinear FDTD modeling of ionospheric cross-modulation experiments." In 2018 International Applied Computational Electromagnetics Society Symposium (ACES). IEEE, 2018. http://dx.doi.org/10.23919/ropaces.2018.8364241.

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Li, Zhangyi, Lixin Guo, Jingchun Li, Benchao Wang, and Yanan Zhao. "Multi-dimensional Time Series Modeling of Ionospheric foF2." In 2020 Cross Strait Radio Science & Wireless Technology Conference (CSRSWTC). IEEE, 2020. http://dx.doi.org/10.1109/csrswtc50769.2020.9372525.

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Meyer, Franz J., and Piyush S. Agram. "Modeling ionospheric phase noise for NISAR mission data." In 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS). IEEE, 2017. http://dx.doi.org/10.1109/igarss.2017.8127829.

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Hobara, Y., M. Iwamoto, K. Ohta, T. Otsuyama, and M. Hayakawa. "TLE producing ionospheric disturbances: Observation and numerical modeling." In 2011 XXXth URSI General Assembly and Scientific Symposium. IEEE, 2011. http://dx.doi.org/10.1109/ursigass.2011.6050944.

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Reports on the topic "Ionospheric modeling"

1

Mahalov, Alex. Multiscale Modeling of Ionospheric Irregularities. Fort Belvoir, VA: Defense Technical Information Center, October 2014. http://dx.doi.org/10.21236/ada612205.

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Doherty, Patricia H., Leo F. McNamara, William J. Burke, William J. McNeil, and Louise C. Gentile. Ionospheric Modeling: Development, Verification and Validation. Fort Belvoir, VA: Defense Technical Information Center, August 2007. http://dx.doi.org/10.21236/ada478630.

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Cummer, Steven A., and Jingbo Li. Accurate Modeling of Ionospheric Electromagnetic Fields Generated by a Low Altitude VLF Transmitter. Fort Belvoir, VA: Defense Technical Information Center, March 2009. http://dx.doi.org/10.21236/ada534986.

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Cummer, Steven A. Accurate Modeling of Ionospheric Electromagnetic Fields Generated by a Low-Altitude VLF Transmitter. Fort Belvoir, VA: Defense Technical Information Center, August 2007. http://dx.doi.org/10.21236/ada519257.

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Tuck, Gary. Visit to Ionospheric Modeling and Remote Sensing Branch, Phillips Laboratory in Hanscom AFB, MA. Fort Belvoir, VA: Defense Technical Information Center, November 1994. http://dx.doi.org/10.21236/ada292339.

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Larmat, Carene, Marcel Remillieux, Lucie Rolland, and Philippe Lognonne. W15_ionisphere “3D modeling and inversion of ionospheric signals driven from below by earthquakes and tsunami". Office of Scientific and Technical Information (OSTI), March 2017. http://dx.doi.org/10.2172/1345919.

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Fox, Matthew W., Xiaoqing Pi, and Jeffrey M. Forbes. First Principles and Applications-Oriented Ionospheric Modeling Studies, and Wave Signatures in Upper Atmosphere Density,. Fort Belvoir, VA: Defense Technical Information Center, January 1997. http://dx.doi.org/10.21236/ada325072.

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Makela, Jonathan. Studies of Ionospheric Plasma Structuring at Low Latitudes from Space and Ground, Their Modeling and Relationship to Scintillations. Fort Belvoir, VA: Defense Technical Information Center, January 2009. http://dx.doi.org/10.21236/ada531096.

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Khattatov, Boris, Michael Murphy, Marianna Gnedin, Tim Fuller-Rowell, and Valery Yudin. Advanced Modeling of the Ionosphere and Upper Atmosphere. Fort Belvoir, VA: Defense Technical Information Center, June 2004. http://dx.doi.org/10.21236/ada429055.

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Roble, Raymond G. Thermosphere-Ionosphere-Mesosphere Modeling Using the TIME-GCM. Fort Belvoir, VA: Defense Technical Information Center, September 2003. http://dx.doi.org/10.21236/ada628807.

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