Results 11 to 20 of about 1,220 (162)
The River Lea 1571-1767: a river navigation prior to canalisation [PDF]
, 1987 PhDIn pre-industrial England river navigations were subject to improvement by canalisation, the introduction of artificial navigation cuts and pound locks. Along the Lea this did not happen until 1767. Before that the navigation, except for one short
Fairclough, Keith Roland
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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
doaj +1 more source
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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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
doaj +1 more source
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
doaj +1 more source
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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A Flexible Ephemeris Representation for GNSS and Alternative PNT Signal Sources Using B-Splines
Navigation, 2023 Most global navigation satellite systems (GNSSs) ephemeris representations require straightforward, albeit specialized algorithms to compute the transmitter position at a time of interest.
Mikaela Dobbin, Penina Axelrad
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Navigation, 2023 The success of drone missions is incumbent on an accurate determination of the drone pose and velocity, which are collectively estimated by fusing inertial measurement unit and global navigation satellite system (GNSS) measurements.
Aman Sharma +2 more
doaj +1 more source