Special Issue "Remote Sensing of Ionosphere Observation and Investigation"

A special issue of Remote Sensing (ISSN 2072-4292). This special issue belongs to the section "Atmosphere Remote Sensing".

Deadline for manuscript submissions: 30 June 2020.

Special Issue Editors

Dr. M Mainul Hoque
E-Mail Website
Guest Editor
Institute of Solar-Terrestrial Physics, German Aerospace Center (DLR), Kalkhorstweg 53, 17235 Neustrelitz, Germany
Tel. +49 3981 480-125
Interests: GNSS ionosphere sounding; space weather; space climate; satellite navigation; geodesy; remote sensing
Special Issues and Collections in MDPI journals
Dr. Raul Orus
E-Mail Website
Co-Guest Editor
Wave Interaction and Propagation Section (TEC-EFW), European Space Research and Technology Centre (ESTEC, ESA), Keplerlaan 1, 2201AZ Noordwijk ZH, The Netherlands

Special Issue Information

Dear Colleagues,

Ionospheric disturbances can affect technologies in space and on Earth, disrupting satellite and airline operations, communications networks, and navigation systems. As the world becomes increasingly dependent on these technologies, ionospheric disturbances—as part of space weather—pose an increasing risk to economic vitality and national security. Advance knowledge of the ionospheric state during space weather events is becoming more and more important.

With the modernization of global navigation satellite systems (GNSS), the use of multi-constellation, multi-frequency observations, including new signals, enables continuous monitoring of the Earth’s ionosphere using worldwide-distributed sensor stations. Other ground-based techniques, such as vertical sounding (VS), incoherent scatter radar (ISR), very low frequency (VLF), or radio beacon (RB) measurements provide complementary ionospheric observations.

The radio occultation (RO) technique provides one of the most effective space-based methods for exploring planetary atmospheres. The availability of numerous medium Earth orbit satellites deployed by GPS, GLONASS, Galileo, BeiDou navigation systems allows continuous monitoring of the Earth’s ionosphere and neutral atmosphere by tracking GNSS signals from low Earth orbit (LEO) satellites. Other space-based techniques include ionosphere estimation using dual-frequency altimeter data (e.g., TOPEX-Poseidon, Jason 2 & 3 missions), using radio beacon measurements from DORIS (geodetic orbit determination and positioning system), receivers onboard LEO satellites, and GNSS reflectometry.

Dr. M Mainul Hoque
Dr. Raul Orus
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Remote Sensing is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • ionosphere
  • GNSS
  • vertical sounding
  • incoherent scatter radar
  • radio beacon
  • radio occultation
  • GNSS reflectometry

Published Papers (6 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Other

Open AccessArticle
Evaluation of E Layer Dominated Ionosphere Events Using COSMIC/FORMOSAT-3 and CHAMP Ionospheric Radio Occultation Data
Remote Sens. 2020, 12(2), 333; https://doi.org/10.3390/rs12020333 - 20 Jan 2020
Abstract
At certain geographic locations, especially in the polar regions, the ionization of the ionospheric E layer can dominate over that of the F2 layer. The associated electron density profiles show their ionization maximum at E layer heights between 80 and 150 km above [...] Read more.
At certain geographic locations, especially in the polar regions, the ionization of the ionospheric E layer can dominate over that of the F2 layer. The associated electron density profiles show their ionization maximum at E layer heights between 80 and 150 km above the Earth’s surface. This phenomenon is called the “E layer dominated ionosphere” (ELDI). In this paper we systematically investigate the characteristics of ELDI occurrences at high latitudes, focusing on their spatial and temporal variations. In our study, we use ionospheric GPS radio occultation data obtained from the COSMIC/FORMOSAT-3 (Constellation Observing System for Meteorology, Ionosphere, and Climate/Formosa Satellite Mission 3) and CHAMP (Challenging Minisatellite Payload) satellite missions. The entire dataset comprises the long period from 2001 to 2018, covering the previous and present solar cycles. This allows us to study the variation of the ELDI in different ways. In addition to the geospatial distribution, we also examine the temporal variation of ELDI events, focusing on the diurnal, the seasonal, and the solar cycle dependent variation. Furthermore, we investigate the spatiotemporal dependency of the ELDI on geomagnetic storms. Full article
(This article belongs to the Special Issue Remote Sensing of Ionosphere Observation and Investigation)
Show Figures

Graphical abstract

Open AccessArticle
Advantages of Uncombined Precise Point Positioning with Fixed Ambiguity Resolution for Slant Total Electron Content (STEC) and Differential Code Bias (DCB) Estimation
Remote Sens. 2020, 12(2), 304; https://doi.org/10.3390/rs12020304 - 17 Jan 2020
Abstract
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Remote Sensing of Ionosphere Observation and Investigation)
Show Figures

Graphical abstract

Open AccessArticle
Understanding Inter-Hemispheric Traveling Ionospheric Disturbances and Their Mechanisms
Remote Sens. 2020, 12(2), 228; https://doi.org/10.3390/rs12020228 - 09 Jan 2020
Abstract
Traveling ionospheric disturbances (TIDs) are wave-like disturbances in ionospheric plasma density. They are often observed during both quiet (medium-scale TID) and geomagnetically disturbed (large-scale TID) conditions. Their amplitudes can reach double-digit percentages of the background plasma density, and their existence presents a challenge [...] Read more.
Traveling ionospheric disturbances (TIDs) are wave-like disturbances in ionospheric plasma density. They are often observed during both quiet (medium-scale TID) and geomagnetically disturbed (large-scale TID) conditions. Their amplitudes can reach double-digit percentages of the background plasma density, and their existence presents a challenge for accurate ionosphere specification. In this study, we examine TID properties using observations obtained during two geomagnetically disturbed periods using multiple ground and space-borne instruments, such as magnetometers, Global Navigation Satellite System (GNSS) receivers, and the SWARM satellite. Reference quiet time observations are also provided for both storms. We use a thermosphere–ionosphere–electrodynamics general circulation model (TIEGCM) results to properly interpret TID features and their drivers. This combination of observations and modeling allows the investigation of variations of TID generation mechanisms and subsequent wave propagation, particularly as a function of different plasma background densities during various geophysical conditions. The trans-equatorial coupling of TIDs in the northern and southern hemispheres is also investigated with respect to attenuation and propagation characteristics. We show that TID properties during trans-equatorial events may be substantially affected by storm time background neutral wind perturbation. Full article
(This article belongs to the Special Issue Remote Sensing of Ionosphere Observation and Investigation)
Show Figures

Graphical abstract

Open AccessArticle
Improved Faraday Rotation Estimation in Spaceborne PolSAR Data Using Total Variation Denoising
Remote Sens. 2019, 11(24), 2943; https://doi.org/10.3390/rs11242943 - 09 Dec 2019
Abstract
Faraday rotation (FR) is a serious problem for spaceborne polarization SAR (PolSAR) systems at L and P bands. One way to solve the problem is to estimate the FR from PolSAR data for further compensation. Therefore, precise estimation of FR from PolSAR data [...] Read more.
Faraday rotation (FR) is a serious problem for spaceborne polarization SAR (PolSAR) systems at L and P bands. One way to solve the problem is to estimate the FR from PolSAR data for further compensation. Therefore, precise estimation of FR from PolSAR data not only determines the compensation effect of polarimetric systems but also benefits the ionospheric sounding with high spatial resolution. Among the factors that affect the FR estimation, system noise is a non-neglectable factor. Although average filtering (AF) has been widely used in previous works for noise removing it depends on large window size, and therefore reduces the spatial resolution of FR estimation. In order to realize optimal noise suppression with minimized resolution loss, the total variation (TV) denoising method is applied in this paper. By testing the Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) full-pol datasets, TV and AF are compared and validated. Results using synthetic and real data show that, after TV denoising, the FR can be recovered with high spatial resolution and the noise level in estimated FR is reduced more effectively than that after AF. Full article
(This article belongs to the Special Issue Remote Sensing of Ionosphere Observation and Investigation)
Show Figures

Graphical abstract

Other

Jump to: Research

Open AccessLetter
Estimation and Analysis of BDS-3 Differential Code Biases from MGEX Observations
Remote Sens. 2020, 12(1), 68; https://doi.org/10.3390/rs12010068 - 23 Dec 2019
Abstract
The third generation of China’s BeiDou Navigation Satellite System (BDS-3) began to provide global services on 27 December, 2018. Differential code bias (DCB) is one of the errors in precise BDS positioning and ionospheric modeling, but the impacts on BDS-2 satellites and receiver [...] Read more.
The third generation of China’s BeiDou Navigation Satellite System (BDS-3) began to provide global services on 27 December, 2018. Differential code bias (DCB) is one of the errors in precise BDS positioning and ionospheric modeling, but the impacts on BDS-2 satellites and receiver DCB are unknown after joining BDS-3 observations. In this paper, the BDS-3 DCBs are estimated and analyzed using the Multi-Global Navigation Satellite System (GNSS) Experiment (MGEX) observations during the period of day of year (DOY) 002–031, 2019. The results indicate that the estimated BDS-3 DCBs have a good agreement with the products provided by the Chinese Academy of Sciences (CAS) and Deutsche Zentrum für Luft- und Raumfahrt (DLR). The differences between our results and the other two products are within ±0.2 ns, with Standard Deviations (STDs) of mostly less than 0.2 ns. Furthermore, the effects on satellite and receiver DCB after adding BDS-3 observations are analyzed by BDS-2 + BDS-3 and BDS-2-only solutions. For BDS-2 satellite DCB, the values of effect are close to 0, and the effect on stability of DCB is very small. In terms of receiver DCB, the value of effect on each station is related to the receiver type, but their mean value is also close to 0, and the stability of receiver DCB is better when BDS-3 observations are added. Therefore, there is no evident systematic bias between BDS-2 and BDS-2 + BDS-3 DCB. Full article
(This article belongs to the Special Issue Remote Sensing of Ionosphere Observation and Investigation)
Show Figures

Figure 1

Open AccessLetter
Statistical Observation of Thunderstorm-Induced Ionospheric Gravity Waves above Low-Latitude Areas in the Northern Hemisphere
Remote Sens. 2019, 11(23), 2732; https://doi.org/10.3390/rs11232732 - 21 Nov 2019
Abstract
Gravity waves (GWs) generated in the lower atmosphere can propagate upwards to ionospheric height. In this study, we investigated the correlation between ionospheric GWs detected by Global Navigation Satellite System (GNSS)-derived total electron content data and thunderstorm events recorded by a local lightning-detection [...] Read more.
Gravity waves (GWs) generated in the lower atmosphere can propagate upwards to ionospheric height. In this study, we investigated the correlation between ionospheric GWs detected by Global Navigation Satellite System (GNSS)-derived total electron content data and thunderstorm events recorded by a local lightning-detection network in the low-latitude region of Southern China during a four-year period, from 2014 to 2017. Ionospheric GWs were detected on both thunderstorm and non-thunderstorm days. Daytime ionospheric GW activity on high-thunderstorm days showed a similar convex-function-like diurnal variation to thunderstorm activity, which is different to the concave-function-like pattern on non-thunderstorm days. Daytime ionospheric GW activity on low-thunderstorm days showed an approximately linear rising trend and was of a larger magnitude than that of high-thunderstorm days, suggesting it may be mixed by non-thunderstorm origins. Night-time enhancement of ionospheric GW activity was observed on thunderstorm days but not on non-thunderstorm days. Furthermore, ionospheric GW activity on thunderstorm days showed a positive correlation to solar activity. These findings can effectively distinguish thunderstorm-related ionospheric GWs from those of non-thunderstorm origins and provide more comprehensive knowledge of thunderstorm–ionosphere coupling in low-latitude areas. Full article
(This article belongs to the Special Issue Remote Sensing of Ionosphere Observation and Investigation)
Show Figures

Graphical abstract

Back to TopTop