Simulation studies of new observing concepts for geodetic Very Long Baseline Interferometry
Licentiatavhandling, 2017

Very Long Baseline Interferometry (VLBI) is a space-geodetic technique in which observations are carried out simultaneously by radio telescopes separated by hundreds or thousands of kilometers. The time difference of signal reception between the telescopes is the basic observable used in geodetic VLBI. This technique is capable of determining all five Earth Orientation Parameters (EOP), which provide the connection between the Earth-fixed and space-fixed reference frames. Currently, there is an ongoing effort concerning the establishment of the VLBI Global Observing System (VGOS), which will significantly improve the present measurement precision and increase the total number of observations per session. This requires the key components of the infrastructure, data handling as well as observation approaches to be upgraded and refined. Thus, the focus of this thesis is set on new observing concepts for VGOS. This includes extensive simulations regarding an improved determination of the rotation of the Earth (UT1-UTC) from one-hour VLBI sessions and investigations on the potential of lunar observations in regular geodetic VLBI sessions. The studies summarized in this work address the main topic from two different aspects, providing valuable insights concerning observations in the VGOS era and stimulating new concepts for space geodesy.

Very Long Baseline Interferometry

space geodesy

Monte Carlo simulations





EC-lecture hall, Hörsalsvägen 11, Chalmers
Opponent: PD Dr.-Ing. Axel Nothnagel, Universität Bonn, Germany


Grzegorz Klopotek

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Results from the VLBI Analysis Software Comparison Campaign 2015

IVS 2016 General Meeting Proceedings "New Horizons with VGOS". Edited by Dirk Behrend, Karen D. Baver, and Kyla L. Armstrong, NASA/CP-2016-219016,; (2016)p. 203-207

Konferensbidrag (offentliggjort, men ej förlagsutgivet)

Implementation of VLBI Near-Field Delay Models in the c5++ Analysis Software

Proceedings of the First International Workshop on VLBI Observations of Near-field Targets, October 5 - 6, 2016, A. Nothnagel and F. Jaron (eds.),; Vol. 54(2017)p. 29-33

Konferensbidrag (offentliggjort, men ej förlagsutgivet)

Identifying optimal tag-along station locations for improving VLBI Intensive sessions

Earth, Planets and Space,; Vol. 69(2017)p. 16-

Artikel i vetenskaplig tidskrift

Klopotek, G., Hobiger, T., Haas, R., 2017. Geodetic VLBI with an artificial radio source on the Moon: A simulation study. Journal of Geodesy.


Onsala rymdobservatorium


Geovetenskap och miljövetenskap

Fusion, plasma och rymdfysik


Chalmers tekniska högskola

EC-lecture hall, Hörsalsvägen 11, Chalmers

Opponent: PD Dr.-Ing. Axel Nothnagel, Universität Bonn, Germany