Results 11 to 20 of about 432 (149)
Improved GPS-Based Single-Frequency Orbit Determination for the CYGNSS Spacecraft Using GipsyX
Navigation, 2023 This paper presents methods for the precise orbit determination (POD) of a satellite in the CYGNSS constellation based on available single-frequency GPS code and carrier measurements. The contributions include the development and evaluation of procedures
Alex V. Conrad +4 more
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Optimized Position Estimation in Mobile Multipath Environments Using Machine Learning
Navigation, 2023 The positioning accuracy of global navigation satellite system receivers is frequently degraded in urban areas due to reflected signals. A moving receiver faces additional challenges because it needs to adjust to changes in the statuses of the signals ...
Nesreen I. Ziedan
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Multi-Parameter Adaptive Notch Filter (MPANF) for Enhanced Interference Mitigation
Navigation, 2023 Interference signals degrade global navigation satellite system (GNSS) performance and must be mitigated. Chirp signals can be mitigated with an adaptive notch filter (ANF), but the dynamic behavior limits performance. An ANF determines the instantaneous
Johannes Rossouw van der Merwe +4 more
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Perspectives on the Systematic (Type B) Uncertainties of UTC-UTC(k)
Navigation, 2023 The systematic uncertainties in the difference between Coordinated Universal Time (UTC) and UTC realizations like UTC(k) are analyzed with a semi-historical algorithm using the uncertainties of the calibrations of only the extant time-transfer links and ...
Demetrios Matsakis
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Navigation, 2023 High-precision ionospheric corrections are essential for precise positioning using low-cost single-frequency GNSS receivers. Although Real-Time Global Ionosphere Maps (RT-GIMs) are available from the International GNSS Service (IGS), their ionospheric ...
Jianping Chen, Yang Gao
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Development of a hydro-environmental model for inland navigational canals [PDF]
Journal of Hydroinformatics, 2013 Before railroad and lorry traffic became common, many canals were built for transportation purposes. Water quality in canals has become a major concern as maintenance of these historically active canals has declined. A generic canal model has been developed to simulate the hydro-environmental processes specifically relevant to inland navigational ...
Xiaolin Wang +2 more
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Performance-Based GNSS Satellite Selection: A Linear Matrix Inequality (LMI) Approach
Navigation, 2023 In the multi-GNSS era, the observable satellites are more than needed and the benefit of processing more than enough satellites is marginal. It is thus desired to select a subset of satellites so that the receiver operation complexity and navigation ...
Jyh-Ching Juang
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SBAS Protection Levels with Gauss-Markov K-Factors for Any Integrity Target
Navigation, 2023 According to aviation minimum operational performance standards (MOPS), protection levels for satellite-based augmentation systems (SBASs) are to be computed as the product of the estimated standard deviation of errors and a scaling, or K-factor.
Julie Antic +2 more
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Asynchronous Method of Simultaneous Object Position and Orientation Estimation with Two Transmitters
Navigation, 2023 This paper proposes an object location method for all types of applications, including the Internet of Things. The proposed method enables estimations of the position and orientation of an object on a plane or in space, especially during motion, by means
Jacek Stefanski, Jaroslaw Sadowski
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Navigation, 2023 Global navigation satellite systems (GNSSs) play a key role in a plethora of applications, ranging from navigation and timing to Earth observation and space weather characterization.
Lorenzo Ortega +3 more
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