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Article
Open AccessTidal harmonics retrieval using GNSS-R dual-frequency complex observations
Tidal analysis and methods for estimation and prediction of ocean tidal constitutes are essential in a large area of scientific disciplines, for example, navigation, onshore and offshore engineering, and produ...
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Chapter
Multi-GNSS Tomography: Case Study of the July 2021 Flood in Germany
Due to climate change, intensive storms and severe precipitation will continue to happen, causing destructive flooding. In July 2021, a series of storms with prolonged rain episodes took place in Europe. Sever...
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Article
Open AccessTropospheric parameters from multi-GNSS and numerical weather models: case study of severe precipitation and flooding in Germany in July 2021
Storms and floods are the most frequent natural disaster in western and central Europe. Due to climate change, intensive storms with prolonged rain episodes will continue to cause even more destructive floodin...
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Article
Snow depth estimation from GNSS SNR data using variational mode decomposition
In recent years, Global Navigation Satellite System-Interferometric Reflectometry (GNSS-IR), a new remote sensing technique, has been widely used to monitor surface signature parameters. In the classical GNSS-...
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Article
Open AccessSporadic E layer characteristics at equatorial latitudes as observed by GNSS radio occultation measurements
Scintillations in the signal-to-noise (SNR) profiles of GNSS radio occultation (RO) measurements at lower ionospheric altitudes are caused by compact layers of high ionization also known as sporadic E (Es) lay...
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Article
Coastal sea-surface wave measurements using software-based GPS reflectometers in Lanyu, Taiwan
A low-cost transportable software-based global positioning system reflectometry (GPS-R) scheme, which can measure sea-surface wave frequency, period, and speed, is proposed and described. We designed and imple...
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Article
Towards a zero-difference approach for homogenizing GNSS tropospheric products
A data homogenization method based on singular spectrum analysis (SSA) was developed and tested on real and simulated datasets. The method identifies abrupt changes in the atmospheric time series derived from ...
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Article
Real-time capturing of seismic waveforms using high-rate BDS, GPS and GLONASS observations: the 2017 Mw 6.5 Jiuzhaigou earthquake in China
The rapid development of the BeiDou Satellite Navigation System (BDS) and other Global Navigation Satellite System (multi-GNSS) constellations provides a great opportunity to contribute to earthquake early war...
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Article
Open AccessGlobal morphology of ionospheric sporadic E layer from the FormoSat-3/COSMIC GPS radio occultation experiment
Ionospheric sporadic-E (Es) activity and global morphology were studied using the 50 Hz signal-to-noise ratio amplitude and excess phase measurements from the FormoSat-3/Constellation Observing System for Mete...
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Article
Multi-GNSS phase delay estimation and PPP ambiguity resolution: GPS, BDS, GLONASS, Galileo
This paper focuses on the precise point positioning (PPP) ambiguity resolution (AR) using the observations acquired from four systems: GPS, BDS, GLONASS, and Galileo (GCRE). A GCRE four-system uncalibrated pha...
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Article
GAMP: An open-source software of multi-GNSS precise point positioning using undifferenced and uncombined observations
As the number of GNSS satellites and stations increases, GNSS data processing software should be developed that is easy to operate, efficient to run, and has a robust performance. To meet these requirements, w...
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Article
Simultaneous estimation of GLONASS pseudorange inter-frequency biases in precise point positioning using undifferenced and uncombined observations
GLONASS precise point positioning (PPP) performance is affected by the inter-frequency biases (IFBs) due to the application of frequency division multiple access technique. In this contribution, the impact of ...
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Article
Initial assessment of the COMPASS/BeiDou-3: new-generation navigation signals
The successful launch of five new-generation experimental satellites of the China’s BeiDou Navigation Satellite System, namely BeiDou I1-S, I2-S, M1-S, M2-S, and M3-S, marks a significant step in expanding Bei...
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Article
Improving BeiDou real-time precise point positioning with numerical weather models
Precise positioning with the current Chinese BeiDou Navigation Satellite System is proven to be of comparable accuracy to the Global Positioning System, which is at centimeter level for the horizontal componen...
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Article
Ionospheric map** functions based on electron density fields
We develop an ionospheric map** function (MF) for the global navigation satellite system (GNSS) which is based on the electron density field derived from the international reference ionosphere (IRI). The sta...
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Article
Tightly coupled integration of multi-GNSS PPP and MEMS inertial measurement unit data
Precise point positioning (PPP) using the Global Positioning System (GPS) is widely recognized as an efficient approach for providing precise positioning services. However, its accuracy and reliability could b...
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Chapter
Zukunft der globalen Geodäsie und Fernerkundung aus Sicht des Deutschen GeoForschungsZentrum (GFZ), Potsdam
Die Technologien und Methoden der Globalen Geodäsie und Fernerkundung (GGF) haben sich in den vergangenen Dekaden mit rascher Geschwindigkeit weiterentwickelt und die Resultate der heutigen GGF liefern wichti...
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Chapter
Monitoring of the Neutral Atmosphere
Global navigation satellite system (GNSS)-based atmosphere sounding techniques have become a widely recognized and operationally used remote sensing tool. A major milestone of this development was the beginning o...
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Article
Long-term soil moisture dynamics derived from GNSS interferometric reflectometry: a case study for Sutherland, South Africa
Soil moisture is a geophysical key observable for predicting floods and droughts, modeling weather and climate and optimizing agricultural management. Currently available in situ observations are limited to sm...
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Article
Improving integer ambiguity resolution for GLONASS precise orbit determination
The frequency division multiple access adopted in present GLONASS introduces inter-frequency bias (IFB) at the receiver-end both in code and phase observables, which makes GLONASS ambiguity resolution rather d...
