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2. Architecture Design and Ground Performance of Netherlands‐China Low‐Frequency Explorer.

Author

Karapakula, Sukanth, Brinkerink, Christiaan, Vecchio, Antonio, Pourshaghaghi, Hamid R., Dolron, Peter, Jordans, Roel, Bertels, Eric, Aalbers, Gerard, Ruiter, Mark, Boonstra, Albert J., Bentum, Mark, Prinsloo, David, Arts, Michel, Bast, Jeanette, Damstra, Sieds, van Duin, Albert, Ebbendorf, Nico, van der Marel, Hans, Morawietz, Juergen, and Witvers, Roel

Subjects
RADIO antennas, MONOPOLE antennas, OBSERVATIONS of the Moon, SIGNAL processing, STAR maps (Astronomy)
Abstract

The Netherlands‐China Low‐Frequency Explorer (NCLE) (Boonstra et al., 2017, https://www.ursi.org/proceedings/procGA17/papers/Paper%5fJ19‐2(1603).pdf; Chen et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AAS...23610203C/abstract) is a radio instrument for astrophysical studies in the low‐frequency range (80 kHz–80 MHz). As a technology demonstrator, NCLE shall inform the design of future radio receivers that aim at low‐frequency radio astronomy. NCLE can make observations at very high spectral resolution (<1 kHz) and generate radio sky maps at an angular resolution of ≈1.5 radians. NCLE uses three monopole antennas, each 5 m long, and three identical analog signal chains to process the signal from each antenna. A single digital receiver samples the signal and calculates the auto‐correlated and cross‐correlated spectra. The instrument's analog and digital signal chains are extensively configurable. They can be fine‐tuned to produce broadband spectra covering the instrument's complete operating frequency range or sub‐bands. NCLE was developed within a veryshort timescale of 2 years, and currently, it is on board Queqiao, the relay spacecraft of the Chang'e‐ 4 mission, in a halo orbit around the Earth‐Moon L2 point. This paper outlines the science cases, instrument architecture with focus on the signal chain, and discusses the laboratory measurements during the pre‐launch phase. Key Points: Radio observations from the Moon at very low frequenciesRadio instrument technology demonstration for future lunar observatory and interferometryRadio receiver design for low‐frequency observation [ABSTRACT FROM AUTHOR]

Published
2024
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3. Surveying and Mapping

Author

Tiberius, Christian, primary, van der Marel, Hans, additional, Reudink, Rene, additional, and van Leijen, Freek, additional

Published
2021
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5. Status of the European Reference Frame (EUREF)

Author

Torres, João Agria, Altamimi, Zuheir, Boucher, Claude, Brockmann, Elmar, Bruyninx, Carine, Caporali, Alessandro, Gurtner, Werner, Habrich, Heinz, Hornik, Helmut, Ihde, Johannes, Kenyeres, Ambrus, Mäkinen, Jaakko, Marel, Hans v d, Seeger, Hermann, Simek, Jaroslav, Stangl, Guenter, Weber, Georg, and Sideris, Michael G, editor

Published
2009
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6. Space-Borne Tsunami Warning System

Author

Brouwer, Peter A.I., Visser, Mark, Molijn, Ramses A., Jara Orué, Hermes M., van Marwijk, Bart J.A., Bermon, Tjerk C.K., van der Marel, Hans, and Olla, Phillip, editor

Published
2009
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7. Status of the European Reference Frame — EUREF

Author

Members of the EUREF Technical Working Group, Adam, Jozsef, Augath, Wolfgang, Boucher, Claude, Bruyninx, Carine, Caporali, Alessandro, Gubler, Erich, Gurtner, Werner, Habrich, Heinz, Harsson, Bjorn Geirr, Hornik, Helmut, Ihde, Johannes, Kenyeres, Ambrus, v. d. Marel, Hans, Seeger, Hermann, Simek, Jaroslav, Stangl, Guenter, Torres, João Agria, Weber, Georg, Sansò, Fernando, editor, Ádám, József, editor, and Schwarz, Klaus-Peter, editor

Published
2002
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9. The European Reference System coming of age

Author

Adam, Josef, Augath, Wolfgang, Boucher, Claude, Bruyninx, Carine, Dunkley, Paul, Gubler, Erich, Gurtner, Werner, Hornik, Helmut, Marel, Hans V. D., Schlüter, Wolfgang, Seeger, Hermann, Vermeer, Martin, Zieliński, Janusz B., and Schwarz, Klaus-Peter, editor

Published
2000
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17. Application of tomographic ionospheric corrections in WADGPS networks for real-time estimation of integrated water vapour

Author

Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Colombo, Oscar L., Van der Marel, Hans, Universitat Politècnica de Catalunya. Departament de Matemàtiques, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. IonSAT - Grup de determinació Ionosfèrica i navegació per SAtèl·lit i sistemes Terrestres, and Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica

Subjects
Previsió del temps, Sistema de posicionament global, Global Positioning System, Física::Electromagnetisme [Àrees temàtiques de la UPC], Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Radionavegació [Àrees temàtiques de la UPC], Weather forecasting
Abstract

In recent years several authors have developed strategies that estimate the Integrated Water Vapor (IWV), proportional to the Zenith Tropospheric Delay (ZTD), in near real time --i.e. with a delay of one hour or more--. The success of these estimations depends on the accuracy of the GPS orbits, so these strategies require that data from a regional GPS network be processed in near real-time, using predicted IGS orbits in combination with partial orbit relaxation. Ambiguity resolution can help determine in real-time such quantities as the ZTD in a regional network. This approach allows any user in the area of the network to get real-time precise ZTD estimates, which can be converted to IWV using measurements of atmospheric pressure. As shown recently, in Wide Area Differential GPS (WADGPS) networks several hundred Km across, double-differenced carrier phase ambiguities can be computed on-the-fly, using a real-time tomographic model of the ionosphere obtained from the same GPS data. The comparison between the real-time strategy presented in this work and the postprocessed approach shows a general agreement of about 1 cm in the ZTD in WADGPS scenarios. This is 30-40% better than without fixing the carrier phase ambiguities. These results can be achieved not only in quiet ionospheric conditions but also during ionospheric disturbances and Solar Maximum conditions. This is also of importance for ionospheric modeling, which is a key element of the technique.

Published
2021

18. Surveying and Mapping

Author

Tiberius, Christian, van der Marel, Hans, Reudink, Rene, and van Leijen, Freek

Subjects
remote sensing, mathematical geodesy, GPS, reference systems, mapping, land surveying
Abstract

This book provides an introduction, at academic level, into the field of surveying and mapping. The book has been compiled based on hand-outs and readers written for the third-year course Surveying and Mapping, in the bachelor program Civil Engineering at Delft University of Technology. This book covers a wide range of measurement techniques, from land surveying, GPS/GNSS and remote sensing to the associated data processing, the underlying coordinate reference systems, as well as the analysis and visualization of the acquired geospatial information.

Published
2021

19. Application of tomographic ionospheric corrections in WADGPS networks for real-time estimation of integrated water vapour

Author

Universitat Politècnica de Catalunya. Departament de Matemàtiques, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. IonSAT - Grup de determinació Ionosfèrica i navegació per SAtèl·lit i sistemes Terrestres, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Colombo, Oscar L., Van der Marel, Hans, Universitat Politècnica de Catalunya. Departament de Matemàtiques, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. IonSAT - Grup de determinació Ionosfèrica i navegació per SAtèl·lit i sistemes Terrestres, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Colombo, Oscar L., and Van der Marel, Hans

Abstract

In recent years several authors have developed strategies that estimate the Integrated Water Vapor (IWV), proportional to the Zenith Tropospheric Delay (ZTD), in near real time --i.e. with a delay of one hour or more--. The success of these estimations depends on the accuracy of the GPS orbits, so these strategies require that data from a regional GPS network be processed in near real-time, using predicted IGS orbits in combination with partial orbit relaxation. Ambiguity resolution can help determine in real-time such quantities as the ZTD in a regional network. This approach allows any user in the area of the network to get real-time precise ZTD estimates, which can be converted to IWV using measurements of atmospheric pressure. As shown recently, in Wide Area Differential GPS (WADGPS) networks several hundred Km across, double-differenced carrier phase ambiguities can be computed on-the-fly, using a real-time tomographic model of the ionosphere obtained from the same GPS data. The comparison between the real-time strategy presented in this work and the postprocessed approach shows a general agreement of about 1 cm in the ZTD in WADGPS scenarios. This is 30-40% better than without fixing the carrier phase ambiguities. These results can be achieved not only in quiet ionospheric conditions but also during ionospheric disturbances and Solar Maximum conditions. This is also of importance for ionospheric modeling, which is a key element of the technique., Peer Reviewed, Postprint (published version)

Published
2021

30. The European Reference System coming of age

Author

Adam, Josef, primary, Augath, Wolfgang, additional, Boucher, Claude, additional, Bruyninx, Carine, additional, Dunkley, Paul, additional, Gubler, Erich, additional, Gurtner, Werner, additional, Hornik, Helmut, additional, Marel, Hans V. D., additional, Schlüter, Wolfgang, additional, Seeger, Hermann, additional, Vermeer, Martin, additional, and Zieliński, Janusz B., additional

Published
2000
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32. Observations outside Radio Astronomy

Author

Scholten, Olaf, primary, Bacelar, Jose, additional, Buitink, Stijn, additional, Falcke, Heino, additional, van der Marel, Hans, additional, Klees, Roland, additional, van Ardenne, Arnold, additional, Mevius, Maaike, additional, Bentum, Mark, additional, Kegel, Koos, additional, and Bos, Andre, additional

Published
2019
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33. Photonic swarm for low frequency radio astronomy in Space

Author

KRUITHOF, Gert, BOONSTRA, Albert-Jan, BRENTJENS, Michiel, MAAT, Peter, VAN DER MAREL, Hans, BENTUM, Mark, Electromagnetics, Center for Wireless Technology Eindhoven, and EM for Radio Science Lab

Subjects
DESIGN, SYSTEMS, STRUCTURES, Physics::Space Physics, FORMATION FLIGHT, Astrophysics::Instrumentation and Methods for Astrophysics, ComputingMilieux_LEGALASPECTSOFCOMPUTING
Abstract

Radio astronomy from 100 kHz to 30 MHz allows compelling science that requires a new space based interferometer at a considerable distance from the Earth. We propose a new satellite concept which has a series of dipole antennas connected to the satellite using tethers. Power over fibre is used to transfer power to the remote antenna units and digital radio over fibre is used to transport the astronomical signal back to the satellite. This approach allows launching an interferometer using only one satellite, and it allows scaling by using multiple satellites. In this paper, the overall preliminary system concept is presented.

Published
2017

38. InSAR datum connection using GNSS-augmented radar transponders.

Author

Mahapatra, Pooja, der Marel, Hans van, van Leijen, Freek, Samiei-Esfahany, Sami, Klees, Roland, and Hanssen, Ramon

Subjects
*INTERFEROMETRY, *SYNTHETIC aperture radar, *GLOBAL Positioning System, *TRANSPONDERS, *PARAMETER estimation
Abstract

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 reference frame, e.g. to compare InSAR results with those of other techniques. We propose a methodology based on collocated InSAR and Global Navigation Satellite System (GNSS) measurements, achieved by rigidly attaching phase-stable millimetre-precision compact active radar transponders to GNSS antennas. We demonstrate this concept through a simulated example and practical case studies in the Netherlands. [ABSTRACT FROM AUTHOR]

Published
2018
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39. Measurements on an autonomous wireless payload at 635 km distance using a sensitive radio telescope

Author

Bentum, Marinus Jan, Leijtens, Johan, Verhoeven, Chris, and van der Marel, Hans

Subjects
METIS-281644, EWI-21005, Physics::Space Physics, Computer Science::Networking and Internet Architecture, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Earth and Planetary Astrophysics, IR-78985
Abstract

The Delfi-C3 spacecraft carries the first autonomous wireless payload in space. This payload is a wireless sun sensor developed by TNO in the Netherlands. The data captured by the sensor is wirelessly transported to the central computer system inside the spacecraft. Since no additional power supply is needed, this sensor is fully autonomous. The radio link is a FSK link at 915 MHz using a standard Nordic Chipset. At the Delfi C3 spacecraft two of these autonomous sun sensors are mounted. Unfortunately only one is operational. Using the Westerbork Synthesis Radio Telescope we tried to detect the 915 MHz signal from the sun sensor to the internal receiver. Before the measurements could be done, the effects of the shielding of the spacecraft case were measured using a spare spacecraft. The final obtained link budget showed a 10 dB SNR when using a 25 meter single dish telescope. Measurements were performed at the WSRT by using multiple radio telescopes placed in the orbit direction. The downlink signal of Delfi C3 was detected, but the 915 MHz signal was not as it should be. We conclude that the sun sensor is malfunctioning.

Published
2011

40. FES-WARTK final presentation

Author

Toledo, M, Fernández-Hernández, I., Verhagen, S, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Aragón Ángel, María Ángeles, Ramos Bosch, Pedro, Odijk, D, De Bakker, Peter, Van der Marel, Hans, Universitat Politècnica de Catalunya. Departament de Física Aplicada, Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada IV, and Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica

Subjects
Sistema de posicionament global, Wide area networks (Computer networks), Global Positioning System, Aeronàutica i espai::Astronàutica::Navegació espacial [Àrees temàtiques de la UPC], Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Satèl·lits i ràdioenllaços [Àrees temàtiques de la UPC], Xarxes de banda ampla (Xarxa d'ordinadors)
Published
2008

41. Status of the European Reference Frame (EUREF)

Author

Torres, João Agria, primary, Altamimi, Zuheir, additional, Boucher, Claude, additional, Brockmann, Elmar, additional, Bruyninx, Carine, additional, Caporali, Alessandro, additional, Gurtner, Werner, additional, Habrich, Heinz, additional, Hornik, Helmut, additional, Ihde, Johannes, additional, Kenyeres, Ambrus, additional, Mäkinen, Jaakko, additional, Marel, Hans v d, additional, Seeger, Hermann, additional, Simek, Jaroslav, additional, Stangl, Guenter, additional, and Weber, Georg, additional

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44. Wide-Area RTK: high precision positioning on a continental scale

Author

Universitat Politècnica de Catalunya. Departament de Física Aplicada, Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada IV, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Van der Marel, Hans, Verhagen, Sandra, De Bakker, Peter, Teunissen, Peter J. G., Odijk, Dennis, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Aragón Ángel, María Ángeles, Ramos Bosch, Pedro, Samson, Jaron, Tossaint, Michel, Albertazzi, Michelangelo, Universitat Politècnica de Catalunya. Departament de Física Aplicada, Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada IV, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Van der Marel, Hans, Verhagen, Sandra, De Bakker, Peter, Teunissen, Peter J. G., Odijk, Dennis, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Aragón Ángel, María Ángeles, Ramos Bosch, Pedro, Samson, Jaron, Tossaint, Michel, and Albertazzi, Michelangelo

Abstract

Real-time corrections at the decimeter level over an entire continent? The challenge lies in minimizing the ranging errors from signals propagating through the Earth’s atmosphere. European researchers describe how it can be done using a Wide Area Real-Time Kinematic concept that exploits the full geometry of the observations, a central processing facility, and undifferenced processing of measurements from widely space GNSS reference receivers to create a real-time ionospheric model of the signal slant delays., Postprint (published version)

Published
2010

45. The proof of concept for 3-cm Altimetry using the Paris Interferometric Technique

Author

Nogues-Correig, Oleguer, Ribó, Serni, Arco, Juan Carlos, Cardellach, Estel, Rius, Antonio, Valencia, Enric, Tarongí, José Miguel, Camps, Adriano, Marel, Hans van der, Martín-Neira, Manuel, Nogues-Correig, Oleguer, Ribó, Serni, Arco, Juan Carlos, Cardellach, Estel, Rius, Antonio, Valencia, Enric, Tarongí, José Miguel, Camps, Adriano, Marel, Hans van der, and Martín-Neira, Manuel

Published
2010

46. FES-WARTK final presentation

Author

Universitat Politècnica de Catalunya. Departament de Física Aplicada, Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada IV, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Toledo, M, Fernández-Hernández, I., Verhagen, S, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Aragón Ángel, María Ángeles, Ramos Bosch, Pedro, Odijk, D, De Bakker, Peter, Van der Marel, Hans, Universitat Politècnica de Catalunya. Departament de Física Aplicada, Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada IV, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Toledo, M, Fernández-Hernández, I., Verhagen, S, Hernández Pajares, Manuel, Juan Zornoza, José Miguel, Sanz Subirana, Jaume, Aragón Ángel, María Ángeles, Ramos Bosch, Pedro, Odijk, D, De Bakker, Peter, and Van der Marel, Hans

Abstract

Postprint (published version)

Published
2008

49. Study of drip line nuclei through two-step fragmentation

Author

Stanoiu, M., Azaiez, F., Becker, F., Belleguic, M., Borcea, C., Bourgeois, C., Brown, B. A., Dlouhy, Z., Dombradi, Z., Fulop, Z., Grawe, H., Grevy, S., Ibrahim, F., Kerek, Andras, Krasznahorkay, A., Lewitowicz, M., Lukyanov, S., van der Marel, Hans, Mayet, P., Mrazek, J., Mandal, S., Guillemaud-Mueller, D., Negoita, F., Penionzhkevich, Y. E., Podolyak, Z., Roussel-Chomaz, P., Saint Laurent, M. G., Savajols, H., Sorlin, O., Sletten, G., Sohler, D., Timar, J., Timis, C., Yamamoto, A., Stanoiu, M., Azaiez, F., Becker, F., Belleguic, M., Borcea, C., Bourgeois, C., Brown, B. A., Dlouhy, Z., Dombradi, Z., Fulop, Z., Grawe, H., Grevy, S., Ibrahim, F., Kerek, Andras, Krasznahorkay, A., Lewitowicz, M., Lukyanov, S., van der Marel, Hans, Mayet, P., Mrazek, J., Mandal, S., Guillemaud-Mueller, D., Negoita, F., Penionzhkevich, Y. E., Podolyak, Z., Roussel-Chomaz, P., Saint Laurent, M. G., Savajols, H., Sorlin, O., Sletten, G., Sohler, D., Timar, J., Timis, C., and Yamamoto, A.

Abstract

We have studied the structure of light neutron-rich nuclei around N = 16 by employing the in-beam gamma-ray spectroscopy technique using the fragmentation of secondary beams of Ne-25,Ne-26, Na-27,Na-28 and Mg-29,Mg-30 isotopes. This secondary-beam cocktail was obtained by the fragmentation of a 36 S beam at 77.5 MeV.A by the SISSI/GANIL facility. By a second-step fragmentation, we have measured gamma-ray-residue coincidences in C17-20 and O-23,O-24 and described the obtained levels in the framework of the shell model., QC 20100525 QC 20111019

Published
2004
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50. N=14 and 16 shell gaps in neutron-rich oxygen isotopes

Author

Stanoiu, M., Kerek, Andras, Van Der Marel, Hans, Yamamoto, A., et., Stanoiu, M., Kerek, Andras, Van Der Marel, Hans, Yamamoto, A., and et.

Abstract

In-beam gamma-ray spectroscopy using fragmentation reactions of both stable and radioactive beams has been performed in order to study the structure of excited states in neutron-rich oxygen isotopes with masses ranging from A=20 to 24. For the produced fragments, gamma-ray energies, intensities, and gamma-gamma coincidences have been measured. Based on this information new level schemes are proposed for O-21,O-22 up to the neutron separation energy. The nonobservation of any gamma-decay branch from O-23 and O-24 suggests that their excited states lie above the neutron decay thresholds. From this, as well as from the level schemes proposed for O-21 and O-22, the size of the N=14 and 16 shell gaps in oxygen isotopes is discussed in the light of shell-model calculations., QC 20100525 QC 20111027. Author count 46

Published
2004
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