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Kabakchiev, Hristo (author), Garvanov, Ivan (author), Behar, Vera (author), Kabakchieva, Dorina (author), Kabakchiev, Kalin (author), Rohling, Hermann (author), Kulpa, Krzysztof (author), Yarovyi, O. (author)
The paper offers new application of a Multi-channel Forward Scatter Radar (MFSR), which uses GPS signals for detection of air targets on their GPS radio shadows. The multi-channel GPS MFSR detector consists of several channels, which process information from several satellites simultaneously. The phenomena of diffraction in the near area is...
journal article 2019
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Krietemeyer, A. (author), ten Veldhuis, J.A.E. (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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Ji, Yangbeibei (author), Xu, Mingwei (author), Li, Jie (author), van Zuylen, H.J. (author)
The macroscopic fundamental diagram (MFD) is a graphical method used to characterize the traffic state in a road network and to monitor and evaluate the effect of traffic management. For the determination of an MFD, both traffic volumes and traffic densities are needed. This study introduces a methodology to determine an MFD using combined...
journal article 2018
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Wang, Kan (author), Chen, Pei (author), Teunissen, P.J.G. (author)
In this contribution, we study the phase-only ambiguity resolution and positioning performance of GPS for short baselines. It is well known that instantaneous (single-epoch) ambiguity resolution is possible when both phase and code (pseudorange) data are used. This requires, however, a benign multipath environment due to the severe effects...
journal article 2018
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Cerqueira, Vitor (author), Moreira Matias, L.A. (author), Khiari, Jihed (author), van Lint, J.W.C. (author)
Floating car data (FCD) denotes the type of data (location, speed, and destination) produced and broadcasted periodically by running vehicles. Increasingly, intelligent transportation systems take advantage of such data for prediction purposes as input to road and transit control and to discover useful mobility patterns with applications to...
journal article 2018
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Frederikse, T. (author), Riva, R.E.M. (author), King, A. Matt (author)
Present-day mass redistribution increases the total ocean mass and, on average, causes the ocean bottom to subside elastically. Therefore, barystatic sea level rise is larger than the resulting global mean geocentric sea level rise, observed by satellite altimetry and GPS-corrected tide gauges. We use realistic estimates of mass...
journal article 2017
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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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Mustafar, Mohamad Asrul (author), Simons, W.J.F. (author), Tongkul, Felix (author), Satirapod, Chalermchon (author), Omar, Kamaludin Mohd (author), Visser, P.N.A.M. (author)
The existence of intra-plate deformation of the Sundaland platelet along its eastern edge in North Borneo, South-East Asia, makes it an interesting area that still is relatively understudied. In addition, the motion of the coastal area of North-West Borneo is directed toward a frontal fold-and-thrust belt and has been fueling a long debate on...
journal article 2017
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Guo, X. (author), Ditmar, P.G. (author), Zhao, Q (author), Klees, R. (author), Farahani, H. (author)
GPS data collected by satellite gravity missions can be used for extracting the long-wavelength part of the Earth’s gravity field. We propose a new data processing method which makes use of the ‘average acceleration’ approach to gravity field modelling. In this method, satellite accelerations are directly derived from GPS carrier phase...
journal article 2017
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Mahapatra, P.S. (author), van der Marel, H. (author), van Leijen, F.J. (author), Samiei Esfahany, S. (author), Klees, R. (author), Hanssen, R.F. (author)
Deformation estimates from Interferometric Synthetic
Aperture Radar (InSAR) are relative: they form a ‘free’
network referred to an arbitrary datum, e.g. by assuming a reference
point in the image to be stable. However, some applications
require ‘absolute’ InSAR estimates, i.e. expressed in
a well-defined terrestrial...
journal article 2017
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Peter-Contesse, H. (author), Jäggi, Adrian (author), Fernández, JJ (author), Escobar, D. (author), Ayuga, F. (author), Arnold, D (author), Wermuth, M. (author), Hackel, S. (author), Otten, M. (author), Simons, W.J.F. (author), Visser, P.N.A.M. (author), Hugentobler, U. (author), Féménias, P. (author)
Sentinel-1A is the first satellite of the European Copernicus programme. Equipped with a Synthetic Aperture Radar (SAR) instrument the satellite was launched on April 3, 2014. Operational since October 2014 the satellite delivers valuable data for more than two years. The orbit accuracy requirements are given as 5. cm in 3D. In order to...
journal article 2017
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Simon, K.M. (author), Riva, R.E.M. (author), Kleinherenbrink, M. (author), Tangdamrongsub, N. (author)
Geodetic measurements of vertical land motion and gravity change are incorporated into an a priori model of present-day glacial isostatic adjustment (GIA) in North America via least-squares adjustment. The result is an updated GIA model wherein the final predicted signal is informed by both observational data, and prior knowledge (or...
journal article 2017
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Hou, Y. (author), Verhagen, A.A. (author), Wu, J (author)
Ambiguity Resolution (AR) plays a vital role in precise GNSS positioning. Correctly-fixed integer ambiguities can significantly improve the positioning solution, while incorrectly-fixed integer ambiguities can bring large positioning errors and, therefore, should be avoided. The ratio test is an extensively used test to validate the fixed...
journal article 2016
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Zaminpardaz, Safoora (author), Teunissen, P.J.G. (author), Nadarajah, Nandakumaran (author)
A first assessment of GLONASS CDMA L3 ambiguity resolution and positioning performance is provided. Our analyses are based on GLONASS L3 data from the satellite pair SVNs 755-801, received by two JAVAD receivers at Curtin University, Perth, Australia. In our analyses, four different versions of the two-satellite model are applied: the...
journal article 2016
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Bekaert, D.P.S. (author), Hooper, A. (author), Wright, T.J. (author)
In Guerrero, Mexico, slow-slip events have been observed in a seismic gap, where no earthquakes have occurred since 1911. A rupture of the entire gap today could result in a Mw 8.2–8.4 earthquake. However, it remains unclear how slow-slip events change the stress field in the Guerrero seismic region and what their implications are for...
journal article 2015
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Lepadatu, L. (author), Tiberius, C.C.J.M. (author)
The Basarab cable-stayed bridge is a newly built structure in Bucharest, Romania, which was inaugurated in June 2011. Before the oficial opening, in order to assure its qualification for trafic, it had to pass several loading tests with convoys of trucks and trams. For this, besides a priori evaluation using the Finite Element Method (FEM),...
journal article 2014
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Jie, L. (author), Van Zuylen, H.J. (author), Chunhua, L. (author), Shoufeng, L. (author)
The travel time is an important measure for the quality of traffic. This paper discusses a few methods to measure or estimate the travel time in urban road networks. First of all, it is important to know that urban travel times display a large variation, so that the measurement of a single (average) travel time is not so meaningful. The travel...
journal article 2011
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Bock, H. (author), Jäggi, A. (author), Meyer, U. (author), Visser, P.N.A.M. (author), Van den IJssel, J.A.A. (author), Van Helleputte, T. (author), Heinze, M. (author), Hugentobler, U. (author)
The first ESA (European Space Agency) Earth explorer core mission GOCE (Gravity field and steady-state Ocean Circulation Explorer) was launched on 17 March 2009 into a sun-synchronous dusk–dawn orbit with an exceptionally low initial altitude of about 280 km. The onboard 12-channel dual-frequency GPS (Global Positioning System) receiver delivers...
journal article 2011
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De Bakker, P.F. (author), Tiberius, C.C.J.M. (author), Van der Marel, H. (author), Van Bree, R.J.P. (author)
Stochastic properties of GNSS range measurements can accurately be estimated using a geometry-free short and zero baseline analysis method. This method is now applied to dual-frequency measurements from a new field campaign. Results are presented for the new GPS L5Q and GIOVE E5aQ wideband signals, in addition to the GPS L1 C/A and GIOVE E1B...
journal article 2011
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Lavallée, D.A. (author), Moore, P. (author), Clarke, P.J. (author), Petrie, E.J. (author), Van Dam, T. (author), King, M.A. (author)
Changes in J2, resulting from past and present changes in Earth's climate, are traditionally observed by Satellite Laser ranging (SLR). Assuming an elastic Earth, it is possible to infer changes in J2 from changes in Earth's shape observed by GPS. We compare estimates of non-secular J2 changes from GPS, SLR, GRACE, and a load model. The GPS and...
journal article 2010
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