****************************************************************************** BSW Electronic Mail 02-Nov-2022 15:45:32 CET Message Number 0393 ****************************************************************************** Author: CODE AC team Subject: Switch to ITRF2020/IGS20 Dear BSW users, The operational IGS processing is intended to be switched to ITRF2020/IGS20 reference frame together with the consistent related antenna model, presumably with the start of GPS week 2238 (27 November 2022). This switch goes along with a number of changes in models and conventions. For more information see: IGSMAIL-8238: https://lists.igs.org/pipermail/igsmail/2022/008234.html IGSMAIL-8256: https://lists.igs.org/pipermail/igsmail/2022/008252.html In addition, further changes and adjustments will be made on the CODE processing/product side. In this notice we will provide an overview of any relevant changes that are intended for CODE IGS20 products. The changes include on IGS level: - Reference frame (from IGb14 to IGS20) - Antenna corrections (igs14.atx to igs20.atx) - Antenna north misalignment (now considered) - Subdaily pole model (DESAI2016) - Mean pole model (IERS2010_V1.2.0) - Phase center corrections applied for undifferened Melbourne-Wuebbena/geometry-free LC - File naming (long filenames) and specifically for CODE products: - GPS+GLONASS+Galileo triple system solutions for all IGS operational product lines (now including final) - SP3 orbit files with 5-minute sampling - Stochastic pulses at orbit midnight - VMF3 - File naming and file compression method (from .Z to .gz) on aftp server: http://ftp.aiub.unibe.ch/CODE http://ftp.aiub.unibe.ch/BSWUSER54 Since August 2022, the IGS is processing the final series based on the IGS20 setup in parallel to the operational products. To support your switch, you may access this series via: https://cddis.nasa.gov/archive/gnss/products/wwww/igs20/ (where wwww indicates the GPS week, e.g. with wwww=2231). These product file names already follow the long filename convention. The same applies for our Repro-3 products at: http://ftp.aiub.unibe.ch/REPRO_2020/CODE/yyyy/ (e.g. with yyyy=2020). The long filename convention will be established also on our ftp server. In particular: CODE: COxwwwwd.EXT.Z to e.g. COD0OPSFIN_20200010000_01D_05M_ORB.SP3.gz BSW52: COxwwwwd.EXT.Z (not affected) BSW54: COx_yyyyddd0.EXT.gz (new naming scheme using .gz instead of .Z) Important note: For CODE ultra-rapid and rapid product lines, we will continue to provide, in addition to the long file names, the short file names until the end of January 2023. For CODE final and MGEX product lines, it is foreseen to provide the product files only using long file names. Within the next days we start to build up our upload scripts into http://ftp.aiub.unibe.ch/CODE_TEST where you are able to develop and test you download scripts as well. Detailed explanations of the respective model changes and the necessary adjustments for BSW52 and BSW54 are given below. In case of any questions regarding this notification, please do not hesitate to contact us. Best regards, The CODE analysis center team Reference frame: the ITRF2020/IGS20 does again consist of coordinates, linear velocities, and non-linear postseismic deformations. The related input files are made available at: BSW, version 5.4: http://ftp.aiub.unibe.ch/BSWUSER54/REF/IGS20_R.CRD http://ftp.aiub.unibe.ch/BSWUSER54/REF/IGS20_R.VEL http://ftp.aiub.unibe.ch/BSWUSER54/REF/IGS20.PSD http://ftp.aiub.unibe.ch/BSWUSER54/REF/IGS20.FIX BSW, version 5.2: http://ftp.aiub.unibe.ch/BSWUSER52/STA/IGS20_R.CRD http://ftp.aiub.unibe.ch/BSWUSER52/STA/IGS20_R.VEL http://ftp.aiub.unibe.ch/BSWUSER52/STA/IGS20.PSD http://ftp.aiub.unibe.ch/BSWUSER52/STA/IGS20.FIX B_108 has to be applied (see http://www.bernese.unibe.ch/support52/Bugs2021-03-27.php) Processing examples: In BPE following the processing examples, the BPE server variables V_REFINF and V_REFPSD need to be changed from IGB14 to IGS20. In PPP-examples also the variable V_REFEPO need to be adjusted from "2010 01 01" to "2015 01 01". Antenna corrections: The related receiver/satellite antenna corrections have to be adapted at the same time: BSW, version 5.4: http://ftp.aiub.unibe.ch/BSWUSER54/REF/I20.ATX http://ftp.aiub.unibe.ch/BSWUSER54/REF/ANTENNA_I20.PCV http://ftp.aiub.unibe.ch/BSWUSER54/CONFIG/SATELLIT_I20.SAT BSW, version 5.2: http://ftp.aiub.unibe.ch/BSWUSER52/GEN/I20.ATX http://ftp.aiub.unibe.ch/BSWUSER52/GEN/PCV_COD.I20 http://ftp.aiub.unibe.ch/BSWUSER52/GEN/SATELLIT.I20 B_109 has to be applied (see http://www.bernese.unibe.ch/support52/Bugs2021-03-27.php) Processing examples: In BPE following the processing examples, the BPE server variable V_PCV need to be changed from I14 to I20. Antenna north misalignment: Starting with IGS20 a potential misaligment of the GNSS-antenna towards north is considered when the coordinates are computed. For most stations this effect is not relevant because the antennas are oriented towards north as requested in the station guidelines. BSW, version 5.4 Indicate potential misorientation angles for affected stations in PART II of the station information file, activate the correction in your processing programs (at least in the final GPSEST) in the checkbox "Consider ant. rotations" available nearby the input field for selecting the "Antenna corrections" (usually panel "GENERAL INPUT FILES"). BSW, version 5.2 You may use the AZI file to select specific antennas that are not oriented towards north. Here an antenna name together with an antenna number has to be spezified. B_110 allows a more flexible session treatment Model changes on IGS level - subdaily pole model: BSW, version 5.4 Exchanges file model: IERS2010XY.SUB -> DESAI2016.SUB In BPE following the processing examples, the BPE server variable V_SUBMOD need to be changed from IERS2010XY to DESAI2016. BSW, version 5.2 Download http://ftp.aiub.unibe.ch/BSWUSER52/GEN/DESAY2016.SUB Exchanges file model: IERS2010XY.SUB -> DESAI2016.SUB in your input panels, e.g., using menu > Configure > Change general options Model changes on IGS level - mean pole model: BSW, version 5.4 Change the mean-pole model in option "Meanpole" from IERS2010 to IERS2010_V1.2.0 in panel POLUPD 2 (Menu > Orbits/EOP / Handle EOP files > Convert IERS to Bernese Format) when creating new Bernese formatted ERP files In BPE following the processing examples, the BPE server variable V_MEANPOLE need to be changed from IERS2010 to IERS2010_V1.2.0. BSW, version 5.2 The new model is not available. Model changes on IGS level - antenna corrections are applied when analyzing Melbourne-Wuebbena linear combination: Even if in case of Melbourne-Wuebbena linear combination (as well as the geometry free linear combination) the geometry cancels out frequency-dependent satellite antenna corrections as they are applied for the first time in IGS20 antenna model have an impact on the resulting biases. In particular when using the phase biases the consistent use for PPP ambiguity resolution is essential. The IGS changes its convention to apply these antenna corrections when computing these biases starting with the switch to the IGS20 antenna model. BSW, version 5.4 Enable option "PCC applied for MELWUEB/L4 LC" in panel GPSEST 3.1 BSW, version 5.2 Not relevant because no PPP ambiguity resolution is supported. [Mailed from: Rolf Dach ]