BNO C1: GGOS Committee on

Performance Simulations and Architectural Trade-Offs (PLATO)

Chair: Alexander Kehm (TUM, Germany)

Co-Chair: Benjamin Männel (GFZ/TU Berlin, Germany)


The Standing Committee PLATO (Performance Simulations and Architectural Trade Offs) has currently 15 member groups working on simulations and new data analysis concepts covering the full range of existing and projected ground and space assets, including VLBI, SLR, LLR, GNSS, and DORIS. The main focus is on how do we use existing observation capabilities (stations, observation concepts, tracking performance, etc.) including co-location in space with existing and new dedicated satellites or satellite constellations to best support GGOS planning and implementation. Amongst all aspects to be studied, the overall goal is to improve the accuracy and stability of the global geodetic reference frame (terrestrial as well as celestial reference frame) in order to fulfill the GGOS requirement (i.e. 1mm in position, and 0.1mm/y in velocity). The main methods to be applied within PLATO are two-fold:

  • Use simulation techniques to assess the impact on reference frame products of network configuration, system performance, technique and technology mix, co-location conditions, site ties, space ties (added spacecraft, etc.), analysis and modeling techniques, etc.;
  • Use and develop improved analysis methods for reference frame products by including all existing data and available co-locations (i.e., include all satellites and use all data types on all satellites by manifesting satellite co-locations);

Investigations that are part of the PLATO activities include the following aspects:

  • Exploiting the full range of existing observations by ground and space assets:
    • GNSS assets (ground and space)
    • SLR (beyond LAGEOS-1 and -2) including ranging to GNSS satellites;
    • LLR assets
    • VLBI assets including tracking of GNSS satellites;
    • Co-located assets in space (e.g. GRACE, OSTM/Jason-2)
    • Improved GNSS antenna calibrations and clock estimation strategies (GNSS alone or when in combination with SLR, VLBI, and DORIS)
  • Study the impact of anticipated improved performance of current systems:
    • Simulate the impact of upgrading existing stations and their procedures
    • Simulate the impact of additional ground surveys at co-location sites (site ties)
    • Investigate the best handling of a mixture of existing legacy stations and simulated next generation stations
  • Study the impact of potential future space assets:
    • Co-locate all four techniques in space on a dedicated satellite (e.g., concept of GRASP or E-GRASP)
    • Exploit the impact of new observation concepts, e.g. inter-satellite links

Based on the studies carried out within PLATO, recommendations on network configurations, co-location sites as well as on optimal strategies for best-possible reference frame products will be provided.

Recent progress/Plans

  • Examining trade-off options for station deployment and closure, technology upgrades, the impact of site ties, etc. and project future network capability based on network configuration projected by the BNO or relevant IAG services (IGS, ILRS, IVS, IDS);
  • Investigating the impact of improved SLR tracking scenarios including spherical satellites, LEOs, and GNSS satellites on reference frame products;
  • Investigating the impact of VLBI satellite tracking on reference frame products;
  • Identifying technique systematics by analyzing short baselines, data from new observation concepts, and available co-locations (e.g., consistent processing of LEO and ground-based observations);
  • Investigating the best-practice methods for co-location in space and assessing the impact of co-location in space on reference frame products based on existing satellites and by simulation studies for proposed missions (e.g. E-GRASP);
  • Develop procedures for exchanging simulated observations between software packages in order to cross-validate simulation studies.


Alexander Kehm (Chair, DGFI-TUM, Germany)
Benjamin Männel (Co-Chair, GFZ Potsdam, Germany)
Rolf Dach (AIUB, Switzerland)
Iván Herrera Pinzón (AIUB, Switzerland)
Daniela Thaller (BKG, Germany)
Mike Pearlman (CfA Harvard, USA)
Mathis Bloßfeld (DGFI-TUM, Germany)
Manuela Seitz (DGFI-TUM, Germany)
Markus Rothacher (ETH Zürich, Switzerland)
Matthias Schartner (ETH Zürich, Switzerland)
Benedikt Soja (ETH Zürich, Switzerland)
Hanane Ait-Lakbir (GET-OPM Toulouse, France)
Robert Heinkelmann (GFZ Potsdam, Germany)
Patrick Schreiner (GFZ Potsdam, Germany)
Urs Hugentobler (IAPG-TUM, Germany)
David Coulot (IGN, France)
Arnaud Pollet (IGN, France)
Liliane Biskupek (IfE Hanover, Germany)
Jürgen Müller (IfE Hanover, Germany)
Richard Gross (JPL, USA)
Ingrid Fausk (Kartverket, Norway)
Eirik Mysen (Kartverket, Norway)
Frank Lemoine (NASA GSFC, USA)
Erricos Pavlis (NASA GSFC/JCET, USA)
Susanne Glaser (Uni Bonn, Germany)
Anton Reinhold (Uni Bonn, Germany)
Johannes Böhm (Uni Wien, Austria)
Tomasz Kur (UPWR Wrocław, Poland)
Joanna Najder (UPWR Wrocław, Poland)
Krzysztof Sośnica (UPWR Wrocław, Poland)

Selected Publications

Ampatzidis D., König R., Glaser S., Schuh H. (2016): The Assessment of the Temporal Evolution of Space Geodetic Terrestrial Reference Frames. IAG Symposia Series IUGG2015, 11–15, DOI 10.1007/1345_2016_251

Anderson J. M., Beyerle G., Glaser S., Liu L., Männel B., Nilsson T., Heinkelmann R., Schuh H. (2018): Simulations of VLBI Observations of a Geodetic Satellite Providing Co-location in Space, Journal of Geodesy 92, 1023–1046, DOI 10.1007/s00190-018-1115-5

Dhar S., Glaser S., Heinkelmann R., Schuh H., Balasubramanian N., Dikshit O. (2023): Favorable Locations for new VGOS Antennas in India depending on the assessment of Geodetic Parameters and Environmental Factors. Earth Planets and Space 75, 47, DOI 10.1186/s40623-023-01794-8

Glaser S., Ampatzidis D., König R., Nilsson T. J., Heinkelmann R., Flechtner F., Schuh H. (2016): Simulation of VLBI observations to determine a global TRF for GGOS. IAG Symposia 147, International Association of Geodesy Symposia, 3–9, DOI 10.1007/1345_2016_256

Glaser S., König R., Ampatzidis D., Nilsson T., Heinkelmann R., Flechtner F., Schuh H. (2017): A Global Terrestrial Reference Frame from simulated VLBI and SLR data in view of GGOS. Journal of Geodesy 91, 723–733, DOI 10.1007/s00190-017-1021-2

Glaser S., König R., Neumayer K. H., Balidakis K., Schuh H. (2019a): Future SLR station networks in the framework of simulated multi-technique terrestrial reference frames, Journal of Geodesy 93, 2275–2291, DOI 10.1007/s00190-019-01256-8

Glaser S., Michalak G., Männel B., König R., Neumayer K. H., Schuh H. (2020a): Reference system origin and scale realization within the future GNSS constellation “Kepler”. Journal of Geodesy 94, 117, DOI 10.1007/s00190-020-01441-0

Herrera Pinzón, I. and Rothacher M. (2018): Assessment of Local GNSS Baselines at Co-Location Sites. Journal of Geodesy 92, 1079–1095, DOI 10.1007/s00190-017-1108-9

Herrera Pinzón I., Rothacher M. (2020): Co-location of Space Geodetic Techniques: Studies on Intra-Technique Short Baselines. In: Freymueller J. T., Sánchez L. (Eds.): Beyond 100: The Next Century in Geodesy. International Association of Geodesy Symposia 152, 29–36, DOI 10.1007/1345_2020_95

Herrera Pinzón I., Rothacher M. and Riepl S (2022): Differencing strategies for SLR observations at the Wettzell observatory. Journal of Geodesy 96, 4, DOI 10.1007/s00190-021-01588-4

Hofmann, F., Biskupek, L., Müller, J. (2018): Contributions to Reference Systems from Lunar Laser Ranging using the IfE analysis model. Journal of Geodesy 92, 975–987, DOI 10.1007/s00190-018-1109-3

Kehm A., Bloßfeld M., Pavlis E., Seitz F. (2018): Future global SLR network evolution and its impact on the terrestrial reference frame. Journal of Geodesy 92, 625–635, DOI 10.1007/s00190-017-1083-1

Kehm A., Bloßfeld M., König P., Seitz F. (2019): Future TRFs and GGOS – where to put the next SLR station? Advances in Geosciences 50, 17–25, DOI 10.5194/adgeo-50-17-2019

König R., Glaser S., Ciufolini I., Paolozzi A. (2019): Impacts of the LARES and LARES-2 satellite missions on the terrestrial reference frame, In: Novák P., Crespi M., Sneeuw N., Sansò F. (Eds.): IX Hotine-Marussi Symposium on Mathematical Geodesy. Proceedings of the Symposium in Rome, June 18 – 22, 2018. International Association of Geodesy Symposia 151, 57–65, DOI 10.1007/1345_2019_84

Kur T., Liwosz T., Kalarus M. (2021). The application of inter-satellite links connectivity schemes in various satellite navigation systems for orbit and clock corrections determination: simulation study. Acta Geodaetica Et Geophysica, 56, 1–28, DOI 10.1007/s40328-020-00322-4

Männel B, Thaller D, Rothacher M, Böhm J, Müller J, Glaser S, Dach R, Biancale R, Bloßfeld M, Kehm A, Herrera Pinzon I, Hofmann F, Andritsch F, Coulot D, Pollet A (2018): Recent Activities of the GGOS Standing Committee on Performance Simulations and Architectural Trade-Offs (PLATO), In: Freymueller J, Sánchez L (Eds.) International Symposium on Advancing Geodesy in a Changing World. International Association of Geodesy Symposia 149, 161–164, DOI:10.1007/1345_2018_30

Otsubo T., Matsuo K., Aoyama Y., Yamamoto K., Hobiger T., Kubo-oka T., Sekido M., Hugentobler U., König R. (2016): Effective expansion of satellite laser ranging network to improve global geodetic parameters. Earth, Planets and Space 68, 65, DOI 10.1186/s40623-016-0447-8

Plank L, Hellerschmied A, McCallum J, Böhm J, Lovell J (2017): VLBI observations of GNSS satellites: from scheduling to analysis. Journal of Geodesy 91, 867–880, DOI 10.1007/s00190-016-0992-8

Pollet A., Coulot D., Biancale R., Pérosanz F., Loyer S., Marty J.-C., Glaser S., Schott-Guilmault V., Lemoine J.-M., Mercier F., Nahmani S., Mandea M. (2023): GRGS numerical simulations for a GRASP-like mission. Journal of Geodesy 97, 45, DOI 10.1007/s00190-023-01730-4

Raut S., Glaser S., Mammadaliyev N., Schreiner P., Neumayer K. H., Schuh H. (2023): Assessing the Potential of VLBI Transmitters on Next Generation GNSS Satellites for Geodetic Products. International Association of Geodesy Symposia, DOI 10.1007/1345_2023_217

Schartner M., Kern L., Nothnagel A., Böhm J., Soja B. (2021): Optimal VLBI baseline geometry for UT1-UTC Intensive observations. Journal of Geodesy 95, 75, DOI 10.1007/s00190-021-01530-8

Tucker E. S., Nerem R. S., Loomis B. D. (2022): Simulation of a Future SLR Satellite to Improve Low-Degree Gravity Estimates. Journal of Geophysical Research: Solid Earth 127(12), e2022JB025743, DOI 10.1029/2022JB025743

Tucker E. S., Nerem R. S., Loomis B. D. (2023): Impacts of SLR ground station geographic distribution on time-variable gravity recovery. Journal of Geophysical Research: Solid Earth 128, e2023JB026638, DOI 10.1029/2023JB026638

Wolf H., Böhm J. (2023): Optimal distribution of VLBI transmitters in the Galileo space segment for frame ties Earth Planets Space 75, 173 (2023), DOI 10.1186/s40623-023-01926-0