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- Eschelbach, Cornelia, et al.
(författare)
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Automated IVS Reference Point Monitoring - First Experience from the Onsala Space Observatory
- 2013
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Ingår i: Reports of the Finnish Geodetic Institute, Proceedings of the 21st Meeting of the European VLBI Group for Geodesy and Astronomy, Ed. by N. Zubko and M. Poutanen. - 0355-1962. - 9789517112970 ; 2013:1:1, s. 249-253
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The realization of the International TerrestrialReference Frame (ITRF) builds upon acombination of results derived from several geodeticspace techniques, such as Very Long Baseline Interferometry(VLBI), Satellite and Lunar Laser Ranging(SLR and LLR) or Global Navigation Satellite Systems(GNSS). To combine the different techniques andtheir results in a meaningful way, co-location sites areimportant where equipment for several techniques islocated reasonably close to each other. The relativegeometries (local tie vectors) between the geometricreference points of the different techniques can bederived by terrestrial survey at these co-locationsites. Within the Global Geodetic Observing System(GGOS) the requirements in terms of e.g. accuracyand frequency of local survey campaigns have beenincreased to guarantee that the local tie vectors reachan utmost level of global accuracy. In response tothis request we developed a concept to achieve automatedand continuous monitoring of radio telescopereference points. This concept was realized and testedin 2012 at the Onsala Space Observatory where anautomated monitoring system was installed for acontinual determination of the reference point ofthe 20 m radio telescope. The results confirm thatuncertainties on the sub-mm level can be achieved withthis approach.
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| 2. |
- Lösler, Michael, et al.
(författare)
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Automated and continual determination of radio telescope reference points with sub-mm accuracy: results from a campaign at the Onsala Space Observatory
- 2013
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Ingår i: Journal of Geodesy. - : Springer Science and Business Media LLC. - 0949-7714 .- 1432-1394. ; 87:8, s. 791-804
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Tidskriftsartikel (refereegranskat)abstract
- The Global Geodetic Observing System (GGOS) requires sub-mm accuracy, automated and continual determinations of the so-called local tie vectors at co-location stations. Co-location stations host instrumentation for several space geodetic techniques and the local tie surveys involve the relative geometry of the reference points of these instruments. Thus, these reference points need to be determined in a common coordinate system, which is a particular challenge for rotating equipment like radio telescopes for geodetic Very Long Baseline Interferometry. In this work we describe a concept to achieve automated and continual determinations of radio telescope reference points with sub-mm accuracy. We developed a monitoring system, including Java-based sensor communication for automated surveys, network adjustment and further data analysis. This monitoring system was tested during a monitoring campaign performed at the Onsala Space Observatory in the summer of 2012. The results obtained in this campaign show that it is possible to perform automated determination of a radio telescope reference point during normal operations of the telescope. Accuracies on the sub-mm level can be achieved, and continual determinations can be realized by repeated determinations and recursive estimation methods.
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