5th International Colloquium Scientific and Fundamental Aspects of the Galileo Programme 27-29 October 2015, Braunschweig, Germany Preliminary Programme Tuesday 27 October 2015 08:00 Registration 09:00 Opening Session Welcome from PTB ESA /D_NAV 09:40 Keynote 1: "ICARUS- New Global Science with Small Animals" Walter Naumann Max-Planck-Institut für Ornithologie (Germany) 10:20 Coffee Break 11:00 Keynote 2: "The new SI: The expected redefinition of the SI units" Joern Stenger PTB (Germany) 11:40 Keynote 3: “To Navigate Autonomously: on Land, in the Atmosphere and Under Water” Annet Ward DLR – German Aerospace Center (Germany) 12:20 Lunch Break 14:00 Session 1A: N1 Multi_GNSS Room 1 The afternoon programme on this day runs in parallel sessions in Rooms 1 and 2 14:00 Precise Point Positioning with Galileo Observables R. White, R. B. Langley University of New Brunswick Geodesy and Geomatics Engineering (Canada) 14:20 MagicPPP in your Pocket: a Smart, Portable and Efficient Multi-GNSS High-accuracy Solution D. Calle, G. Tobias González, I. Rodriguez Perez, R. Rosa Ferrero, P. F. Navarro Madrid GMV (Spain) 14:40 Interoperability of the GNSS's for Positioning and Timing Applications 1 2 2 A. Caporali , L. Nicolini , M. Bertocco 1 2 University of Padova (Italy), University of Padova – CISAS (Italy) 15:00 Coffee Break 15:30 Analysis of Multi-GNSS Observations and the Challenges of their Combination 1 1 2 2 1 2 F. Reichel , E. Schönemann ,T. Springer ,M. Becker ,W. Enderle 1 2 Technische Universität Darmstadt (Germany), ESA/ESOC (Germany) 15:50 GFZ Analysis Centre: Multi-GNSS Processing and Products M. Fritsche, Z. Deng, M. Uhlemann, T. Nischan, M. Bradke, M. Ramatschi, A. Brandt, G. Beeskow Deutsches GeoForschungsZentrum GFZ (Germany) 16:10 Utilization of a Novel Channel Quality Index for Improved Multi-GNSS Positioning in GNSSdenied Environments M.Z.H. Bhuiyan, S. Söderholm, H. Kuusniemi, S. Thombre, L. Ruotsalainen Finnish Geospatial Research Institute (Finland) 14:00 Session 1B: E2 Ionosphere Observation Room 2 The afternoon programme on this day runs in parallel sessions in Rooms 1 and 2 14:00 Evaluation of Parameters Pertaining to Observed Ionosphere Anomalies in Europe with Multi-GNSS and Validation with Space Weather Products G. Lalgudi Gopalakrishnan, J. Feltens Telespazio VEGA Deutschland Gmbh (Germany) 14:20 Extrapolated Ionospheric GNSS Tomography to Support SBAS: Design and Proof of Concept over Eastern Asia 1 1 2 1 M. Hernandez-Pajares , G. Olivares-Pulido , H. So , A. Garcia-Rigo 1 2 UPC-IonSAT (Spain), ADD (South Korea), 14:40 Ionosphere Scintillation at Low and High Latitudes (Modelling vs Measurement) Y. Beniguel IEEA (France) 15:00 Coffee Break 15:30 High Accuracy Measurements of Ionospheric Parameters by Combining Radio-astronomical and GNSS Observations. 1 1 1 1 2 2 H. Zelle , E. A. Kuijpers A. J. P. Van Kleef , F. Wokke , J. E. Noordam , B. Van der Tol , 2 M. Mevius 1 2 NLR (The Netherlands), ASTRON (The Netherlands) 15:50 Inversion of Tsunami Height Using Ionospheric Observations. The case of the 2012 Haida Gwaii Tsunami 1 1 2 R. Virgile , P. Lognonné , L. Rolland 1 2 IPGP (France), Géoazur (France) 16:10 NeQuick G performance and residual error overbounding: 2 year global study R. Orus ESA/ESTEC (the Netherlands) 16:30 Poster Session 18:00 Poster + Icebreaker 2 Wednesday 28 October 2015 09:00 Session 2A:N2 Challenges in GNSS Applications Room 1 The programme on this day runs in parallel sessions in Rooms 1 and 2 09:00 On the Benefits of Atomic Clocks in Autonomous GNSS Navigation T. Krawinkel, S. Schoen Leibniz Universität Hannover, Institut für Erdmessung (Germany) 09:20 Numerical Weather Modelling Based Troposphere Correction for Real Time Precise Point Positioning 1 1 2 3 L. Yang , C. Hill , J. Jones , R. Prieto-Cerdeira 1 2 3 University of Nottingham (United Kingdom), UK Met Office (United Kingdom), ESA/ESTEC (The Netherlands) 09:40 Kinematic GNSS Experiment Supported by External Tropospheric Corrections P. Vaclavovic, J. Dousa, M. Elias Geodetic Observatory Pecny, RIGTC, p.r.i. (Czech Republic) 10:00 Refined and Site-augmented Tropospheric Delay Models for GNSS D. Landskron, G. Möller, A. Hofmeister, J. Böhm, R. Weber TU Wien (Austria) 10:20 Coffee Break 10:50 A Contribution to ETRS89 in Central Europe: Results from the CEGRN Activity 1 2 3 4 5 6 7 A. Caporali , M. Barlik , M. Becker , G. Grenerczy , J. Hefty , D. Medak , G. Milev , M. 5 8 9 10 11 4 12 Mojzes , M. Mulic , T. Rus , J. Simek , G. Stangl , G. Virag , J. Zurutuza 1 2 3 University of Padova (Italy), Warsaw University of Technology (Poland), TU Darmstadt 4 5 (Germany), Satellite Geodetic Observatory, Penc (Hungary), TU Bratislava (Slovakia), 6 7 8 University of Zagreb (Croatia), Bulgarian Academy of Sciences (Bulgaria), University of 9 Sarajevo (Bosnia and Herzegovina), Technical University of Civil Engineering, Bucharest 10 11 (Romania), Czech Academy of Sciences (Czech Republic), Austrian Academy of Sciences 12 (Austria), University of Padova (Italy) 11:10 Characterization of Velocity Field in Iberian Peninsula with Continuous GNSS (1998-2014) 1 2 2 3 I. Quintanilla , M. Valdes , J. A. Sánchez , J. Velasco 1 2 Technical University of Valencia (Spain), Instituto Geográfico Nacional (IGN) (Spain), 3 Technical University of Madrid (Spain) 11:30 Submillimetric GNSS Distance Determination for Metrological Purposes S. Baselga, L. García-Asenjo, P. Garrigues Universidad Politécnica de Valencia (UPV) (Spain) Combined Architecture for Multi-dimensional Signal Quality Enhancements in GNSS Receivers 1 2 3 4 5 N. G. Ferrara , , S. Sánchez-Naranjo , F. A. González , R. Ramos-Pollán , 6 3 2 1 G. Seco-Granados , M. Solé , M. Toledo , E. S. Lohan 1 2 3 Tampere University of Technology (Finland), GMV (Spain), Pildo Labs (Spain), 4 5 Universidad Nacional de Colombia (Colombia), Universidad Industrial de Santander 11:50 3 6 (Colombia), Universitat Autònoma de Barcelona (Spain) 09:00 Session 2B: M2 Galileo/GNSS orbit determination Room 2 The programme on this day runs in parallel sessions in Rooms 1 and 2 09:00 The Galileo Terrestrial Reference Frame and the Galileo Orbit Validation Facility 1 1 2 3 1 4 R. Zandbergen , E. Schoenemann , T. Springer , J. Martin , W. Enderle , M. Uhlemann , M. 4 5 5 5 6 6 7 7 Fritsche , R. Dach , L. Prange , E. Orliac , Z. Altamimi , J. Chenal , W. Soehne , J. Dostal , A. 7 8 8 8 Rülke , F. Gonzalez , R. Swinden , S. Binda 1 2 3 4 ESA/ESOC (Germany), Positim UG (Germany), Telespazio Vega (Germany), Helmholtz 5 6 7 Zentrum Potsdam (GFZ) (Germany), University of Bern (Switzerland), IGN (France), BKG 8 (Germany), ESA/ESTEC (The Netherlands) 09:20 Precise Orbit and Clock Determination of the Galileo FOC Satellites P. Steigenberger, O. Montenbruck DLR/GSOC (Germany) 09:40 Results from CODE's Multi-GNSS Orbit Solution 1 1 1 1 1 2 1 L. Prange , E. Orliac , R. Dach , D. Arnold , G. Beutler , S. Schaer , A. Jäggi 1 2 AIUB (Switzerland), Swisstopo(Switzerland) 10:00 Precise Orbit Determination for GNSS Satellites 1 1 1 1 1 2 E. Schoenemann , T. Springer , F. Dilssner , C. Garcia Serrano , C. Flohrer , F. Reichel , 1 1 W. Enderle , R. Zandbergen 1 2 ESA/ESOC (Germany), Technische Universität Darmstadt (Germany) 10:20 Coffee Break 10:50 Accelerometers for GNSS Orbit Determination U. Hugentobler, A. Schlicht Technische Universität München (Germany) 11:10 Towards MEO Microaccelerometer for GNSS R. Peresty, M. Peca, J. Kraus SERENUM, a. s. (Czech Republic) 11:30 Positioning Accuracy Using a Combination of GNSS and Inter-Satellite Observations M. Stetter, U. Hugentobler Technische Universität München (Germany) 11:50 Laser Ranging to Galileo (LR2G) S Dell’Ag ell INFN-LNF (Italy) 12:10 Lunch Break 14:00 Session 3A: E3 Atmospheric Research Room 1 The programme on this day runs in parallel sessions in Rooms 1 and 2 4 14:00 A 17 Year Time Series of Ground-based GNSS for Sensing of Atmospheric Water Vapour: Assessment of the Quality through Two Different Data Analyses G. Elgered, T. Ning Chalmers University of Technology (Sweden) 14:20 A New Mapping Function Recovered from Atmospheric Profiles Retrieved by GNSS Radio Occultation Data 1 1 1 2 D.R. Vespe , C. B. Benedetto , E. Rosciano , G. Vizziello 1 2 ASI – Agenzia Spaziale Italiana (Italy) , Consorzio INNOVA (Italy) 14:40 COST Action ES1206 : Advanced Global Navigation Satellite Systems Tropospheric Products for Monitoring Severe Weather Events and Climate (GNSS4SWEC) 1 2 3 4 5 6 7 8 J. Jones , G. Guerova , J. Dousa , S. de Haan ,E. Pottiaux , O. Bock , R. Pacione , G. Dick 1 2 3 Met Office (United Kingdom), Sofia University (Bulgaria), Geodetic Observatory of Pecny 4 5 (Czech Republic), Royal Netherlands Meteorological Institute (The Netherlands), Royal 6 7 Observatory of Belgium(Belgium), Institute Geographique National (France), e-geos S.p.A. 8 ASI/Centro di Geodesia Spaziale (Italy), GFZ German Research Centre for Geosciences (Germany) 15:00 Coffee Break 15:30 GNSS Meteorology to Compute Weighted Mean Temperature and its Parameters for Turkey C. Mekik, I. Deniz, G. Gurbuz Bulent Ecevit University (Turkey) 15:50 Towards real-time GNSS troposphere delay monitoring service for Poland T.H. Hadas, J. Kaplon, J. Bosy Wroclaw University of Environmental and Life Sciences (Poland) 16:10 The Potential of Galileo Inter-Satellite Ranging for Atmospheric Research G. Möller, F. Hinterberger, A. Hofmeister, R. Weber TU Wien (Austria) 14:00 Session 3B: M3 Timing Room 2 The programme on this day runs in parallel sessions in Rooms 1 and 2 14:00 Galileo Signals for Time and Frequency Users 1 1 1 1 2 2 P. Defraigne , W. Huang , N. Bergeot , J. M. Chevalier , G. Cerretto ,E. Cantoni , 3 4 A. Perucca ,A. Mudrak 1 2 Royal Observatory of Belgium (Belgium), Istituto Nazionale di Ricerca Metrologica (Italy), 3 4 aizoOn (Italy), ESA/ESTEC (The Netherlands) 14:20 Calibration and Distribution of UTC from Galileo 1 1 1 2 2 3 3 R. Píriz , P. Roldán , A. Cruz , A. Bauch , J. Leute ,J. Díaz ,E. Marín 1 2 3 GMV (Spain), PTB (Germany), Seven Solutions (Spain) 14:40 TBD 5 15:00 Coffee Break 15:30 High-rate Clock Variations of the Galileo IOV-1/2 Satellites and their Impact on Carrier Tracking of Geodetic Receivers 1 1 2 3 3 O. Montenbruck , A. Hauschild , A. Häberling ,G. Katsigianni , U. Hugentobler 1 2 3 DLR / GSOC (Germany), ETH (Switzerland), TUM/IAPG (Germany) 15:50 GNSS Time Transfer in the Context of BIPM Activities 1 2 2 2 G. Petit , J. Leute , D. Piester , A. Bauch 1 2 BIPM (France), PTB (Germany) 16:10 TBD 16:30 Poster Session 18:00 Departure to Downtown 19:00 Conference Dinner 6 Thursday 29 October 2015 09:00 Session 4A: E1 Status and Trends in Earth Observation Room 1 The programme on this day runs in parallel sessions in Rooms 1 and 2 09:00 GEROS-ISS: Innovative Ocean Remote Sensing Using GNSS Reflectometry Onboard the International Space Station 1 2 3 4 5 2 6 J. Wickert , O. Andersen , B. Chapron , E. Cardellach , J. Hatton , P. Hoeg , A. Jäggi , N. 7 5 8 5 9 10 1 Jakowski , M. Kern , T. Lee , M. Martin-Neira ,N. Pierdicca , C. K. Shum , M. Semmling , 8 C. Zuffada 1 2 3 GFZ Potsdam ( Germany), Technical University of Denmark (Denmark), IFremer (France), 4 5 IEEC/ICE-CSIC, Institute of Space Sciences (Spain), ESA/ESTEC (The Netherlands), 6 7 8 University of Bern (Switzerland), DLR (Germany), Jet Propulsion Laboratory, Caltech 9 10 (United States), Sapienza University of Rome (Italy), Ohio State University (United States) 09:20 Current Research Activities at UPC on Earth Remote Sensing using GNSS-R A. Camps, H. Park, H. Carreno-Luengo, A. Alonso-Arroyo, D. Pascual, R. Onrubia, J. Querol Universitat Politecnica de Catalunya-Barcelona Tech (Spain) 09:40 Resolution Improvement of GNSS-based Bistatic Synthetic Aperture Radar Using Combined Galileo E5 Signals 1 2 3 1 4 M. Antoniou , H. Ma , J. Winkel , M. Cherniakov ,C. Buck 1 2 3 University of Birmingham (United Kingdom), Beihang University (China), IFEN GmbH 4 (Germany), ESA/ESTEC (The Netherlands) 10:00 Determination of Temporal Changes in the Earth's Gravitational Field Using Optical Twoway Links between GALILEO and LEO Satellites M. Hauk, M. Murböck, R. Pail, A. Schlicht TUM (IAPG) (Germany) 10:20 Use of GNSS Tropospheric Products and Numerical Weather Prediction Model to Study Fog in Bulgaria 1 2 3 D. Guerova , M. Stoycheva ,M. Manafov 1 2 Sofia University (Bulgaria), National Institute of Meteorology and Hydrology (Bulgaria), 3 Bulatsa (Bulgaria) 10:40 Coffee Break 09:00 Session 4B: P1 Fundamental Physics Room 2 The programme on this day runs in parallel sessions in Rooms 1 and 2 09:00 Test of the Gravitational Redshift Using Galileo Satellites 5 and 6 1 1 1 2 3 P. Delva , E. Richard , P. Wolf , A. Hees , S. Bertone 1 2 Syrte/Observatoire de Paris/UPMC (France), Department of Mathematics, Rhodes 3 University (South Africa), Astronomical Institute, University of Bern (Switzerland) 7 09:20 Clocks in Space 1 1 1 1 1 1 C. Lämmerzahl , E. Hackmann , M. List , S. Herrmann , V. Perlick , D. Puetzfeld , 2 1 F. Merkle , B. Rievers 1 2 ZARM, University of Bremen (Germany), OHB Systems (Germany) 09:40 The Time Transfer and Synge World Functions in Relativistic Positioning Systems 1 2 A. Heffernan , C. Gerekos 1 2 ESA/ESTEC (The Netherlands), Université Libre de Bruxelles (Belgium) 10:00 General Relativistic Experiments Using Accelerometry and Eccentric Orbits of GALILEO Satellites D. Vespe ASI – Agenzia Spaziale Italiana (Italy) 10:20 TBC 10:40 Coffee Break 11:10 Session 5A: N3 GNSS Signal Processing Room 1 The programme on this day runs in parallel sessions in Rooms 1 and 2 11:10 A Review of Pre-despreading GNSS Interference Detection Techniques A. Jafarnia Jahromi, S. Daneshmand, A. Broumandan, G. Lachapelle University of Calgary (Canada) 11:30 Simulink-based Open-source Simulator for the Narrowband Interference Mitigation in E5a Galileo Band D. Alonso de Diego , N. G. Ferrara, J. Nurmi, E. S. Lohan TUT (Finland) 11:50 Effectiveness of GPS-GALILEO Inter-frequency Biases due to Mixed Signal Types on Ambiguity Resolution and Integrity Applications G. Lalgudi Gopalakrishnan, H. Boomkamp, J. Feltens Telespazio VEGA Deutschland Gmbh (Germany) 12:10 A Context-Aware GNSS Multipath Compensation Algorithm based on Pattern Recognition Approaches N. Sokhandan Asl, A. Broumandan, G. Lachapelle University of Calgary (Canada) 11:10 Session 5B: M1 : Clock Development and Use Room 2 The programme on this day runs in parallel sessions in Rooms 1 and 2 11:10 High Stability Double-modulation CPT Cesium Compact Clock P. Jun, S. Mejri, F. Tricot, E. de Clercq, S. Guerandel Observatoire de Paris (France) 8 11:30 MuClock: a Commercial Cold Atom Clock for Ground Applications 1 2 2 2 2 2 1 J. F. Schaff , R. Szmuk , M. Langlois , L. de Sarlo , D. Holleville , N. Dimarcq , B. Desruelle 1 2 Muquans (France), SYRTE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, LNE (France) 11:50 Towards a Highly Compact Rb Atomic clock with Improved Stability for Space Applications C. Affolderbach, M. Gharavipour, S. Kang, F. Gruet, G. Mileti University of Neuchatel (Switzerland) 12:10 Stable Clocks for Precise Orbit Determination and Navigation T. Romanyuk, U. Hugentobler TUM (Germany) 12:30 ESA / Local 12:45 CLOSE COLLOQUIUM 12:45 Lunch in PTB casino (self-organized) 14:00 Guided tours to PTB laboratories 9 Poster Sessions P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 Evaluation of Possibilities of Using Precise Point Positioning Method to Determine Orthometric Heights G Krz , K D d cz, K Ś ąte University of Warmia and Mazury in Olsztyn (Poland) Reliable Receiver Quality Assessment by Means of a Record and Playback System D. Spiegel Technical University of Braunschweig (Germany) Improved MSTID Modelling and Impact on Precise GNSS Processing 1 2 3 2 2 M. Hernandez – Pajares , P. Wielgosz , J. Paziewski , A. Krypiak-Gregorczyk , K. Stepniak , 3 3 3 4 5 5 1 J. Bosy , J. Kaplon , T. Hadas ,R. Orus-Perez , E. Monte-Moreno , H. Yang , A. García-Rigo , 1 G. Olivares-Pulido 1 2 3 4 UPC-IonSAT (Spain), UWM (Poland), WUELS (Poland), ESA/ESTEC (The Netherlands), 5 UPC (Spain) NWM Forecast Monitoring with (Near) Real-time GNSS Tropospheric Products 1 2 1 1 1 J. Dousa , P. Krc ,M. Elias , K. Eben , J. Resler 1 2 Geodetic Observatory Pecny, RIGTC, p.r.i. (Czech Republic), Institute of Computer Science, Academy of Sciences (Czech Republic) An Evaluation of Multi-GNSS Zenith Tropospheric Delay Products based on Real-time Satellite Products 1 1 1 2 W. Ding , K. E. Abraha , F. N. Teferle , D. Laurichesse 1 2 University of Luxembourg (Luxembourg), CNES - Centre National d'Etudes Spatiales(France) Seismo-ionospheric Imaging: the Multi-GNSS Revolution L. Rolland Geoazur (France) Evaluation of CODE Multi-GNSS Clock Solution 1 1 1 1 1 2 1 E.O. Orliac , L. Prange , R. Dach , D. Arnold , G. Beutler , S. Schaer ,A. Jaeggi 1 2 AIUB - Astronomical Institute of University of Bern (Switzerland), Swisstopo (Switzerland) GNSS Time Transfer: Multiple Techniques for Antenna Cable Delay Measurement 1 1 1 2 P. U. Uhrich , G. D. Rovera , M. Abgrall , M. Siccardi 1 2 LNE-SYRTE Observatoire de Paris (France), SKK ELectronics (France) Broadband Two-way Satellite Time and Frequency Transfer and GNSS for Optical Clock Comparison 1 1 1 1 2 2 3 3 F. Riedel , E. Benkler , J. Leute , D. Piester , J. Achkar , P. Delva , I. Sesia , G. Cerretto , P. 4 5 5 5 Defraigne , P. Whibberley , S. Shemar , H. S. Margolis 1 2 Physikalisch-Technische Bundesanstalt (Germany), LNE-SYRTE / Observatoire de Paris, 3 4 LNE, CNRS, UPMC (France), Istituto Nazionale di Ricerca Metrologica (Italy), Royal 5 Observatory Belgium (Belgium), National Physical Laboratory (United Kingdom) GNSS-based Frequency Comparison of Yb-171 Ion Optical Clocks at PTB and NPL 1 1 1 1 2 2 J. Leute , N. Huntemann , B. Lipphardt , C. Tamm , P. B. R. Jones ,R. M. Godun , J. M. 2 2 2 2 3 3 2 1 Jones , S. A. King ,H. S. Margolis , P. Whibberley , A. Wallin , M. Merimaa , P. Gill , E. Peik 10 1 2 PTB - Physikalisch-Technische Bundesanstalt (Germany), National Physical Laboratory 3 (United Kingdom), VTT Technical Research Centre of Finland ltd (Finland) P11 P12 Benefits from GNSS Receiver Clock Modeling for Low Earth Orbiters C. Wallat, S. Schön Leibniz Universität Hannover (Germany) Real-time Global Ionospheric Modelling from GNSS Data with RT-TOMION Model: Actual Performances, Comparisons and Potential Improvements 1 1 2 2 D. Roma – Donase , J. M. Gomez-Cama , M. Hernández – Pajares , A. García-Rigo 1 2 Dept. Electronics, Faculty of Physics, UB (Spain), UPC-IonSAT (Spain) SEPsFLAREs Prediction System for the Anticipation of Space Weather Events Affecting Ionosphere and GNSS Satellite Systems 1 2 3 3 4 5 A. García-Rigo , M. Núñez , R. Qahwaji ,O. Ashamari , M. Hernández-Pajares ,P. Jiggens , 4 5 G. Pérez , A. Hilgers P13 1 UPC-IonSAT (Spain), 2Space Weather Group, University of Malaga (UMA) (Spain), Space Weather Research Group, Bradford University (UoB) (United Kingdom), 3 4 5 UPC-IonSAT (Spain), ESA Space Environments & Effects section (TEC-EES), ESA-ESTEC (The Netherlands) P14 MONITOR Assessment of St. Patrick’s Day 2015 Geomagnetic Storm Impact on EGNOS 1 2 3 4 3 M. Hernandez – Pajares , R. Prieto-Cerdeira ,Y. Beniguel , A. García-Rigo ,J. Kinrade , K. 5 2 6 7 8 9 10 Kauristie ,R. Orus-Perez , S. Schlueter , D. Serant ,B. Nava ,A. Krankowski , H. Secretan , R. 11 12 Sampedro , X. Prats 1 2 3 4 UPC-IonSAT (Spain), ESA/ESTEC (The Netherlands), IEEA (France), UPC-IonSAT (Spain), 5 Finnish Meteorological Inst.(Finland), 6ESA/EPO (France), 7Thales Alenia Space/France(France), 8ICTP (Italy), 9University of Warmia and Mazury in Olsztyn 10 11 12 (Poland), CNES (France), UPC (Spain), UPC/Icarus (Spain) P15 P16 P17 P18 Influence of Real-time Products Latency on Kinematic PPP Results 1 2 1 1 1 A. Martin , T. Hadas ,A. Dimas , A. B. Anquela , J. L. Berne 1 2 Technical University of Valencia (Spain), Wroclaw University of Environmental and Life Sciences(Poland) Effects of Changing the Antenna Phase Center Calibration Model in Sub-daily Position Time Series K. Dawidowicz, G. Krzan , R. Baryla, J. Rapinski University of Warmia and Mazury (Poland) A Study on Selected Aspects of GPS and Galileo Observation Integration in Precise Positioning J. Paziewski, P. Wielgosz, R. Sieradzki, M. Krukowska University of Warmia and Mazury in Olsztyn (Poland) Signal Obstructions at GNSS Stations: Benefits From Multi-GNSS Observations 1 1 1 2 K. E. Abraha , F. N. Teferle , A. Hunegnaw , R. Dach 1 2 University of Luxembourg (Luxembourg), Astronomical Institute, University of Bern (Switzerland) 11