VLBI module of VieVS

Written by present and former members of the TU Wien VieVS-team

Administrated by Sigrid Böhm ([email protected])

Documentation: https://vievswiki.geo.tuwien.ac.at

VieVS-VLBI VLBI module of Vienna VLBI and Satellite Software

Copyright (C) 2019 TU Wien

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

If you publish results obtained with VieVS-VLBI, please give credit to the VieVS-team by citing the current reference:

Johannes Böhm, Sigrid Böhm, Janina Boisits, Anastasiia Girdiuk, Jakob Gruber, Andreas Hellerschmied, Hana Krásná, Daniel Landskron, Matthias Madzak, David Mayer, Jamie McCallum, Lucia McCallum, Matthias Schartner, Kamil Teke, Vienna VLBI and Satellite Software (VieVS) for Geodesy and Astrometry, Publications of the Astronomical Society of the Pacific, Vol. 130(986), 044503, 2018. http://iopscience.iop.org/article/10.1088/1538-3873/aaa22b

You need a recent Matlab installation (R2016b or later). VieVS is tested on Windows and Linux. Download or clone the VLBI repository and(!) the COMMON repository and put them to the same directory. If your main directory is called 'VieVS' for example, your folder structure should look like this:

/VieVS/COMMON/
/VieVS/VLBI/

Please be aware that this repository contains more or less only the program code. The data files necessary for processing have to be downloaded from external sources.

• Please note: in order to access the data achive of CDDIS you need an Earthdata Login as described here https://www.earthdata.nasa.gov/centers/cddis-daac/archive-access.
• NGS can be downloaded for example from https://cddis.nasa.gov/archive/vlbi/ivsdata/ngs/ and have to be stored in year folders (NGS-files have to be uncompressed): /VLBI/DATA/NGS/yyyy/
• vgosDB can be downloaded from https://cddis.nasa.gov/archive/vlbi/ivsdata/vgosdb/ and have to be stored in year folders as you download them (compressed tar files, *.tgz or *.tar.gz): /VLBI/DATA/vgosDB/yyyy/
• Master files are needed for the automatic generation of a process list, they can be downloaded from https://cddis.nasa.gov/archive/vlbi/ivscontrol/ as yearly *.txt files and have to be stored in : /VLBI/DATA/MASTER

• Since 2025-07-07 all data files necessary or recommended for standard processing can be downloaded with one button press directly from the Welcome panel. These are EOP files (finals, C04, JPL), mapping function files (VMF3), and non-tidal atmospheric loading files (NTAL/VIE).
• Usage: go to the Welcome panel (it appears when you start VieVS-VLBI and you can go back to it via the menu: File ➤ Welcome panel ), enter the required year or time range into the input field and press Download.
• The files are renamed and downloaded to the correct directories (those described below) automatically.
• Data from CDDIS (vgosDB, master files,...) cannot be downloaded automatically because they require an Earthdata Login.
• If you want to use VMF1, gradients, or ray-traced delays follow the instructions below.

• Please note: the instructions for EOP download are obsolete if you use the Download button on the Welcome panel in the GUI.
• EOP C04 can be downloaded from https://datacenter.iers.org/data/latestVersion/EOP_20_C04_one_file_1962-now.txt. Take "EOP_20_C04_one_file_1962-now.txt" and store it as C04_20_1962_now.txt in /VLBI/EOP/.
• EOP finals can be downloaded from https://datacenter.iers.org/data/latestVersion/finals.all.iau2000.txt. Take "finals.all.iau2000.txt" and store it as finals_all_IAU2000.txt in /VLBI/EOP/.

• Please note: if you do not need more than VMF3 and non-tidal atmospheric loading (NTAL/VIE) you can use the GUI Download button described above and ignore these instructions.
• Mapping functions: VMF1 and VMF3 can be retrieved from http://vmf.geo.tuwien.ac.at/trop_products/VLBI/ . Choose the yearly files and store them in the respective folder (VMF1 or VMF3) in /VLBI/TRP/.
• Gradients are available from http://vmf.geo.tuwien.ac.at/trop_products/VLBI/GRAD/ . Choose the yearly files and store them in the respective folder in /VLBI/TRP/GRAD.
• Ray-traced delays are available from http://vmf.geo.tuwien.ac.at/trop_products/VLBI/RAYTR/RADIATE/. The *.radiate files have to be stored in year folders in /VLBI/TRP/RAYTRACING_DATA/yyyy/.
• Non-tidal station loading: files with information about non-tidal station loading have to be placed into the respective directories in /VLBI/NTSL/. Atmospheric pressure loading has to be stored in /VLBI/NTSL/NTAL/. If you would like to use NTAL from the VMF server, download the yearly files from http://vmf.geo.tuwien.ac.at/APL_products/VLBI/yearly/, rename the yYYYY.apl_r files to vie_yYYYY.ntal_r and store them in /VLBI/NTSL/NTAL/VIE/. Other non-tidal station loading: functions to reformat data on hydrological loading (HYDL) and non-tidal ocean loading (NTOL) from other institutions to yearly files readable by VieVS will be provided in future.

Start Matlab, go to VLBI/WORK and type vievs in the command window to start the VieVS graphical user interface.