Searched for: subject%3A%22precise%255C+pointing%22
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Bezsilla, Janos (author)
Nowadays, many space missions require highly accurate pointing for Earth observation or cosmic vision purposes. However, the vibration environment from a spacecraft's structure and reaction wheels can cause disturbances in its line-of-sight stability and severely impact image quality. Additionally, these effects are not known precisely due to...
master thesis 2023
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Hou, P. (author), Zha, Jiuping (author), Liu, Teng (author), Zhang, Baocheng (author)
Precise point positioning-real-time kinematic (PPP-RTK), otherwise known as integer ambiguity resolution-enabled precise pointing positioning, has attracted much attention in recent years and has become state-of-the-art in the global navigation satellite system (GNSS) high-precision positioning community. This work reviews several PPP-RTK...
journal article 2023
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Khodabandeh, A. (author), Teunissen, P.J.G. (author), Psychas, D. (author)
To obtain single-receiver Global Navigation Satellite System (GNSS) parameter solutions, the PPP-RTK user-filter combines measurements with time-correlated corrections that are separately computed by the filter of an external provider. The consequence of exercising such double-filtering is that the Kalman filter’s standard assumption of...
journal article 2023
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Sadegh Nojehdeh, Parvaneh (author), Khodabandeh, Amir (author), Khoshelham, Kourosh (author), Amiri Simkooei, A. (author)
The provision of accurate ionospheric corrections in PPP-RTK enormously improves the performance of single-receiver user integer ambiguity resolution (IAR), thus enabling fast high precision positioning. While an external provider can disseminate such corrections to the user with a time delay, it is the task of the user to accurately time...
journal article 2023
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Psychas, D.V. (author)
Precise Point Positioning (PPP) is a Global Navigation Satellite Systems (GNSS) modelling and processing method that provides single-receiver users with high positioning accuracy anywhere on the globe, without the explicit dependence on reference receivers. The realization of PPP is based on undifferenced code and phase measurements, a priori...
doctoral thesis 2022
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Teunissen, P.J.G. (author), Khodabandeh, A. (author)
In this contribution, we generalize PPP–RTK theory by allowing the transmitters to transmit on different frequencies. The generalization is based on the integer-estimability theory of Teunissen (A new GLONASS FDMA model. GPS Solutions, 2019). As the theory and associated algorithms provided are generally applicable, they apply to satellite...
journal article 2022
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Bezsilla, János (author), Takarics, Bela (author), Vanek, Bálint (author), Guo, J. (author)
This article focuses on the validation of a classical PID controller scheme for flexible spacecraft with regards to the effect of parameter uncertainty on system stability and pointing precision. A high-fidelity simulation environment with external disturbances was built in Simulink using a control-oriented model of an Earth-observing...
journal article 2022
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Psychas, D.V. (author), Teunissen, P.J.G. (author), Verhagen, S. (author)
The single-receiver integer ambiguity resolution-enabled variant of precise point positioning (PPP), namely PPP-RTK, has proven to be crucial in reducing the long convergence time of PPP solutions through the recovery of the integerness of the user-ambiguities. The proliferation of global navigation satellite systems (GNSS) supports various...
journal article 2021
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Haji Aghajany, S. (author), Amerian, Yazdan (author), Verhagen, S. (author), Rohm, Witold (author), Schuh, Harald (author)
Tropospheric wet delay, the main source of which is water vapor, is one of the major factors affecting the accuracy of positioning techniques using microwave. Tropospheric tomography is a powerful method to reconstruct the water vapor content in four-dimensional (4D) space. This paper studies the effect of using function-based and voxel-based...
journal article 2021
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Ma, H. (author), Verhagen, S. (author), Psychas, D.V. (author), Monico, João Francisco Galera (author), Marques, Haroldo Antonio (author)
The technology of integer ambiguity resolution-enabled precise-point-positioning (also referred to as PPP-AR) has been proven capable of providing comparable accuracy, efficiency, and productivity to long-baseline real-time kinematic positioning (RTK) during the last decade. Commercial PPP-AR services have been provided by different...
journal article 2021
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Yang, M. (author)
Multi-epoch Synthetic Aperture Radar Interferometry (InSAR) is widely used to estimate displacements of selected scatterers from phase observations. However, their interpretation needs a connection to objects in the real world. <br/><br/>To associate InSAR scatterers to their corresponding geo-objects, it is necessary to (i) accurately estimate...
doctoral thesis 2020
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Ackaert, Gilles (author)
For any space mission, the communication subsystem is an indispensable part of the satellite that carries the payload. Traditionally, on-board antennas transmitting Radio Frequency (RF) waves to the receiver have been used. Nowadays, laser communications is becoming increasingly popular due to its potential to become a license-free, secure and...
master thesis 2020
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Pang, Menglin (author), Tiberius, C.C.J.M. (author)
This paper presents an approach to analyse the quality, in terms of precision and reliability, of a system which integrates-at the observation-level-landmark positions and GNSS measurements, obtained with a single camera and a digital map, and a single frequency GNSS receiver respectively. We illustrate the analysis by means of design...
journal article 2020
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Ma, H. (author), Zhao, Qile (author), Verhagen, S. (author), Psychas, D.V. (author), Dun, H. (author)
This contribution implements the Kriging interpolation in predicting the tropospheric wet delays using global navigation satellite system networks. The predicted tropospheric delays can be used in strengthening the precise point positioning models and numerical weather prediction models. In order to evaluate the performances of the Kriging...
journal article 2020
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Ssenyunzi, Richard Cliffe (author), Oruru, Bosco (author), D'ujanga, Florence Mutonyi (author), Realini, Eugenio (author), Barindelli, Stefano (author), Tagliaferro, Giulio (author), van de Giesen, N.C. (author)
The Global Navigation Satellite System (GNSS) can be used to derive accurately the Zenith Tropospheric Delay (ZTD) under all-weather conditions. The derived ZTDs play a vital role in climate studies, weather forecasting and are operationally assimilated into numerical weather prediction models. In this study, variations and statistical...
journal article 2019
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Krietemeyer, A. (author), ten Veldhuis, Marie-claire (author), van der Marel, H. (author), Realini, Eugenio (author), van de Giesen, N.C. (author)
Dual-frequency Global Navigation Satellite Systems (GNSSs) enable the estimation of Zenith Tropospheric Delay (ZTD) which can be converted to PrecipitableWater Vapor (PWV). The density of existing GNSS monitoring networks is insufficient to capture small-scale water vapor variations that are especially important for extreme weather...
journal article 2018
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Wang, Kan (author), Khodabandeh, Amir (author), Teunissen, P.J.G. (author), Nadarajah, Nandakumaran (author)
The real-time kinematic precise point positioning (PPP-RTK) technique enables integer ambiguity resolution by providing singlereceiver users with information on the satellite phase biases next to the standard PPP corrections. Using undifferenced and uncombined observations, rank deficiencies existing in the design matrix need to be eliminated to...
journal article 2018
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Zhang, Baocheng (author), Teunissen, P.J.G. (author), Yuan, Yunbin (author), Zhang, Hongxing (author), Li, Min (author)
Vertical total electron content (VTEC) parameters estimated using global navigation satellite system (GNSS) data are of great interest for ionosphere sensing. Satellite differential code biases (SDCBs) account for one source of error which, if left uncorrected, can deteriorate performance of positioning, timing and other applications. The...
journal article 2018
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de Bakker, P.F. (author), Tiberius, C.C.J.M. (author)
Precise Point Positioning (PPP) is a popular Global Positioning System (GPS) processing strategy, thanks to its high precision without requiring additional GPS infrastructure. Single-Frequency PPP (SF-PPP) takes this one step further by no longer relying on expensive dual-frequency GPS receivers, while maintaining a relatively high...
journal article 2017
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De Bakker, P.F. (author)
Precise Point Positioning (PPP) is a Global Navigation Satellite System (GNSS) processing method with the objective of providing high positioning accuracy without the need for a nearby base station or dense network of reference stations operated by the user. To reach this objective, PPP uses the very precise carrier phase measurements in...
doctoral thesis 2016
Searched for: subject%3A%22precise%255C+pointing%22
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