============================================================================= INTERNATIONAL GNSS SERVICE CODE Analysis Strategy Summary ============================================================================= | Analysis Center | Center for Orbit Determination in Europe (CODE) | | | Astronomical Institute | | | University of Bern | | | Sidlerstrasse 5 | | | CH-3012 Bern | | | Switzerland | | | E-mail: code(at)aiub.unibe.ch (CODE AC Team) | | | Phone: +41-31-684-8593 | | | Data archive: ftp://ftp.aiub.unibe.ch/CODE/ | | | http://www.aiub.unibe.ch/download/CODE/ | | | Web: http://www.aiub.unibe.ch (CODE at AIUB) | | | http://www.bernese.unibe.ch (Bernese SW)| |---------------------------------------------------------------------------| | Contact People | E-mail: code(at)aiub.unibe.ch (CODE AC Team) | |---------------------------------------------------------------------------| | Software Used | Bernese GNSS Software Version 5.5, developed at AIUB | |---------------------------------------------------------------------------| | GNSS system(s) | GPS, GLONASS, Galileo, BeiDou, QZSS | |---------------------------------------------------------------------------| | List of CODE's | ftp://ftp.aiub.unibe.ch/AIUB_AFTP.TXT | | analysis products | http://www.aiub.unibe.ch/download/AIUB_AFTP.TXT | | | | | Final Products | Product reference: | | generated for | Dach, R., S. Schaer, D. Arnold, E. Brockmann, | | GPS week 'wwww' | M. Kalarus, L. Prange, P. Stebler, A. Jaeggi (2023). | | day of week 'n' | CODE final product series for the IGS. Published | | (d=0,1,...,6) | by Astronomical Institute, University of Bern. | | day of year 'ddd' | URL: http://www.aiub.unibe.ch/download/CODE/yyyy; | | year 'yy'|'yyyy' | DOI: 10.48350/185744. | | month 'mm' | | | | Files generated from three-day long-arc solutions: | | | COD0OPSFIN_yyyyddd0000_01D_05M_ORB.SP3.gz | | | (old: CODwwwwd.EPH.Z) | | | CODE final GPS+GLONASS+Galileo | | | orbits | | | COD0OPSFIN_yyyyddd0000_01D_01D_ERP.ERP.gz | | | (old: CODwwwwd.ERP.Z) | | | CODE final ERPs belonging to the final| | | orbits | | | COD0OPSFIN_yyyyddd0000_01D_30S_CLK.CLK.gz | | | COD0OPSFIN_yyyyddd0000_01D_30S_CLK.CLK_V2.gz | | | (old: CODwwwwd_v3.CLK.Z) | | | (old: CODwwwwd.CLK.Z) | | | CODE final clock product, clock RINEX | | | format (versions 3.04 and 2.00) | | | with a sampling of 30 sec. | | | for the GNSS satellite and reference | | | (station) clock corrections and | | | 5 minutes for all other for | | | all other station clock corrections | | | COD0OPSFIN_yyyyddd0000_01D_05S_CLK.CLK.gz | | | COD0OPSFIN_yyyyddd0000_01D_05S_CLK.CLK_V2.gz | | | (old: CODwwwwd_v3.CLK.Z) | | | (old: CODwwwwd.CLK.Z) | | | CODE final clock product, clock RINEX | | | format (versions 3.04 and 2.00) | | | with a sampling of 5 sec. | | | for the GNSS satellite and reference | | | (station) clock corrections and | | | 5 minutes for all other for | | | all other station clock corrections | | | COD0OPSFIN_yyyyddd0000_01D_01D_OSB.BIA.gz | | | (old: CODwwwwd.BIA.Z | | | CODE daily code and phase bias | | | solution corresponding to the | | | above mentioned clock products, | | | bias SINEX format V1.00 | | | COD0OPSFIN_yyyyddd0000_01D_30S_ATT.OBX.gz | | | (old: CODwwwwd.OBX.Z) | | | Satellite attitude information | | | in ORBEX format | | | COD0OPSFIN_yyyyddd0000_01D_01D_SOL.SNX.gz | | | (old: CODwwwwd.SNX.Z) | | | CODE daily final solution | | | in SINEX format | | | COD0OPSFIN_yyyyddd0000_01D_01H_TRO.TRO.gz | | | (old: CODwwwd.TRO.Z) | | | CODE final troposphere product | | | in troposphere SINEX format | | | COD0OPSFIN_yyyyddd0000_01D_01H_GIM.INX.gz | | | (old: CODGddd0.yyI.Z) | | | CODE final ionosphere product | | | in IONEX format | | | COD0OPSFIN_yyyyddd0000_01D_01H_GIM.ION.gz | | | (old: CODwwwwd.ION.Z) | | | CODE final ionosphere product | | | in Bernese format | | | COD0OPSFIN_yyyyddd0000_01D_01D_GIM.RNX.gz | | | (also still available | | | CGIMddd0.yyN.Z) | | | Improved Klobuchar-style | | | ionosphere coefficient in | | | navigation RINEX format | | | COD0OPSFIN_yyyyddd0000_07D_07D_SOL.SNX.gz | | | (old: CODwwww7.SNX.Z) | | | CODE weekly final solution in | | | SINEX format | | | (only for Sunday of the related week) | | | COD0OPSFIN_yyyyddd0000_07D_01D_ERP.ERP.gz | | | (old: CODwwww7.ERP.Z) | | | Collection of the 7~daily CODE-ERP | | | solutions of the week | | | (only for Sunday of the related week) | | | COD0OPSFIN_yyyyddd0000_07D_01D_SUM.SUM.gz | | | (old: CODwwww7.SUM.Z) | | | CODE weekly summary file | | | (only for Sunday of the related week) | | | | | | Other product files: | | | | | | P1C1yymm.DCB.Z CODE monthly P1-C1 code bias solutions| | | in Bernese format | | | containing only the GPS satellites | | | P1P2yymm.DCB.Z GNSS monthly P1-P2 code bias | | | solutions in Bernese format | | | containing the GPS and GLONASS | | | satellites | | | P1P2yymm_ALL.DCB.Z GNSS monthly P1-P2 code bias | | | solutions in Bernese format | | | containing the GPS and GLONASS | | | satellites and all stations used | | | P1C1yymm_RINEX.DCB.Z CODE monthly P1-C1 DCB values | | | directly extracted from RINEX | | | observation files | | | in Bernese format | | | P2C2yymm_RINEX.DCB.Z CODE monthly P2-C2 DCB values | | | directly extracted from RINEX | | | observation files | | | in Bernese format | | | Remarks: | | | | | | EPH: Orbit positions correspond to the estimates | | | for the middle day of a 3-day in case of a | | | long-arc analysis. | | | CLK: Clock corrections are consistent with | | | carrier phase as well as P1/P2 pseudorange | | | measurements. | | | CODE P1-C1 pseudorange bias values of a | | | moving 30-day solution are considered to | | | correct C1/X2 and C1/P2 receiver data. | | | BIA: The usage of the phase biases for ambiguity | | | resolution in PPP applications is explained | | | in ftp://ftp.aiub.unibe.ch/CODE/IAR_README.TXT | | | EPH/ERP/SNX/TRO: These products are extracted from | | | one inversion of the normal equation based | | | either on a long-arc or clean one-day | | | solution. | | | | | Rapid Products | Product reference: | | generated daily | Dach, R., S. Schaer, D. Arnold, E. Brockmann, | | | M. Kalarus, L. Prange, P. Stebler, A. Jaeggi (2023). | | | CODE rapid product series for the IGS. Published | | | by Astronomical Institute, University of Bern. | | | URL: http://www.aiub.unibe.ch/download/CODE; | | | DOI: 10.48350/185740. | | | | | | | | | Two sets of rapid products are generated at CODE: | | | Early rapid solution: generated in the morning and | | | is the last day of a three-day long-arc solution | | | Final rapid solution: updated rapid solution in the | | | context of the ultra-rapid processing; middle | | | day of a long-arc solution computed from the | | | current and previous day's rapid plus the ultra- | | | rapid solution from the subsequent day | | | | | | | | | Result files from the final rapid solution: | | | | | | CODMOPSRAP_yyyyddd0000_01D_05M_ORB.SP3 | | | (old: CODwwwwd.EPH_M) | | | CODE final rapid GNSS orbits | | | CODMOPSRAP_yyyyddd0000_01D_01D_ERP.ERP | | | (old: CODwwwwd.ERP_M) | | | CODE final rapid ERPs belonging | | | to the final rapid orbits | | | CODMOPSRAP_yyyyddd0000_01D_30S_CLK.CLK | | | CODMOPSRAP_yyyyddd0000_01D_30S_CLK.CLK_V2 | | | (old: CODwwwwd.CLK_M) | | | CODE final rapid clock product | | | belonging to the final rapid orbits | | | clock RINEX format | | | (versions 3.04 and 2.00) | | | CODMOPSRAP_yyyyddd0000_01D_01D_OSB.BIA | | | code/phase biases related to the | | | final rapid orbit and clock | | | corrections, bias SINEX format | | | V1.00 | | | | | | Result files from the early rapid solution: | | | | | | COD0OPSRAP_yyyyddd0000_01D_05M_ORB.SP3 | | | (old: CODwwwwd.EPH_R) | | | CODE early rapid GNSS orbits | | | COD0OPSRAP_yyyyddd0000_01D_01D_ERP.ERP | | | (old: CODwwwwd.ERP_R) | | | CODE early rapid ERPs belonging | | | to the early rapid orbits | | | COD0OPSRAP_yyyyddd0000_01D_30S_CLK.CLK | | | COD0OPSRAP_yyyyddd0000_01D_30S_CLK.CLK_V2 | | | (old: CODwwwwd.CLK_R) | | | CODE early rapid clock product | | | belonging to the early rapid orbits | | | clock RINEX format | | | (versions 3.04 and 2.00) | | | COD0OPSRAP_yyyyddd0000_01D_01H_TRO.TRO | | | (old: CODwwwwd.TRO_R) | | | CODE rapid troposphere product, | | | troposphere SINEX format | | | COD0OPSRAP_yyyyddd0000_01D_01D_SOL.SNX | | | (old: CODwwwwd.SNX_R.Z) | | | SINEX file from the CODE rapid | | | solution containing station | | | coordinates, ERPs, and satellite | | | antenna Z-offsets, SINEX format | | | COD0OPSRAP_yyyyddd0000_01D_02H_TRO.SNX | | | (old: CODwwwwd_TRO.SNX_R.Z) | | | CODE rapid solution, as above but | | | with troposphere parameters for | | | selected sites, SINEX format | | | COD0OPSRAP_yyyyddd0000_01D_01D_OSB.BIA | | | code/phase biases related to the | | | final rapid orbit and clock | | | corrections, bias SINEX format | | | V1.00 | | | COD0OPSRAP_yyyyddd0000_01D_30S_ATT.OBX | | | Satellite attitude, ORBEX format | | | COD0OPSRAP_yyyyddd0000_01D_01H_GIM.INX.gz | | | (old: CORGddd0.yyI) | | | CODE rapid ionosphere product, | | | IONEX format | | | COD0OPSRAP_yyyyddd0000_01D_01H_GIM.ION | | | (old: CODwwwwd.ION_R) | | | CODE rapid ionosphere product, | | | Bernese format | | | COD0OPSRAP_yyyyddd0000_01D_01D_GIM.RNX | | | (old: CGIMddd0.yyN_R) | | | Improved Klobuchar-style coefficients | | | based on CODE rapid ionosph. product, | | | RINEX format | | | Remarks: | | | | | | EPH: Orbit positions correspond to the estimates | | | for the last day of a 3-day long-arc analysis. | | | CLK: Clock corrections are consistent with carrier | | | phase as well as P1/P2 pseudorange | | | measurements. | | | CODE P1-C1 pseudorange bias values of a moving | | | 30-day solution are considered to correct | | | C1/X2 and C1/P2 receiver data. | | | | | | | | Ultra Rapid | Product reference: | | Products updated | Dach, R., S. Schaer, D. Arnold, E. Brockmann, | | every 6 hours | M. Kalarus, L. Prange, P. Stebler, A. Jaeggi (2023). | | | CODE ultra-rapid product series for the IGS. Published| | | by Astronomical Institute, University of Bern. | | | URL: http://www.aiub.unibe.ch/download/CODE; | | | DOI: 10.48350/185741. | | | | | | | | | COD0OPSULT.SP3 (old: COD.EPH_U) | | | CODE ultra-rapid GNSS orbits | | | (GPS+GLONASS+Galileo) | | | COD0OPSULT.ERP (old: COD.ERP_U) | | | CODE ultra-rapid ERPs belonging to | | | the ultra-rapid GNSS orbit product | | | COD0OPSULT.TRO (old: COD.TRO_U) | | | CODE ultra-rapid troposphere product, | | | troposphere SINEX format | | | COD0OPSULT.SNX (old: COD.SNX_U.Z) | | | SINEX file from the CODE ultra-rapid | | | solution containing station | | | coordinates, ERPs, and satellite | | | antenna Z-offsets | | | COD0OPSULT_TRO.SNX (old: COD_TRO.SNX_U.Z) | | | CODE ultra-rapid solution, | | | as above but with troposphere | | | parameters for selected sites, | | | SINEX format | | | COD0OPSULT.SUM (old: COD.SUM_U) | | | Summary of stations used for the | | | latest ultra-rapid orbit product | | | COD0OPSULT.ION (old: COD.ION_U) | | | Last update of CODE rapid | | | ionosphere product (1 day) | | | complemented with ionosphere | | | predictions (2 days), | | | Bernese format | | | COD0OPSULT_yyyyddd0000_01D_05M_ORB.SP3 | | | (old: CODwwwwd.EPH_U) | | | CODE ultra-rapid GNSS orbits from the | | | 24UT solution available until the | | | corresponding early rapid orbit | | | is available (to ensure a complete | | | coverage of orbits even if the early | | | rapid solution is delayed after the | | | first ultra-rapid solution of the day)| | | COD0OPSULT_yyyyddd0000_01D_01D_ERP.ERP | | | (old: CODwwwwd.ERP_U) | | | CODE ultra-rapid ERPs belonging to | | | the above ultra-rapid GNSS orbits | | | | | | Remarks: | | | | | | EPH: Orbit positions correspond to the estimates | | | for the last 24 hours of a 3-day long-arc | | | analysis plus predictions for the following | | | 24 hours | | | EPH/ERP/TRO/SNX: Files contain generally results | | | of last update | | | ION: Last rapid ionosphere product complemented by | | | all available ionosphere predictions | | | | | | | | Predictions | COD0OPSPRD_05D.SP3 (old: CODwwwwd.EPH_5D) | | updated every 6 | CODE 5-day GNSS orbit predictions | | hours | COD0OPSPRD_yyyyddd0000_05D_05M_ORB.SP3 | | | (old: CODwwwwd.EPH_5D) | | | CODE 5-day GNSS orbit predictions | | | COD0OPSPRD_yyyyddd0000_21D_06H_ERP.ERP | | | (old: CODwwwwd.ERP_5D) | | | CODE predicted ERPs belonging to | | | the predicted orbits | | | COD0OPSPRD_yyyyddd0000_01D_01H_GIM.INX.gz | | | (old: COPGddd0.yyI) | | | CODE ionosphere predictions, | | | IONEX format | | | COD0OPSPRD_yyyyddd0000_01D_01H_GIM.ION | | | (old: CODwwwwd.ION_P) | | | CODE ionosphere predictions, | | | Bernese format | | | COD0OPSPRD_yyyyddd0000_01D_01D_GIM.RNX | | | (old: CGIMddd0.yyN_P) | | | predictions of improved Klobuchar- | | | style coefficients, RINEX format | | | | | | Remarks (for old filename style): | | | | | | "P2" indicates 2-day predictions (24-48 hours); | | | "P" indicates 1-day predictions (0-24 hours). | | | "5D" indicates files containing predicted | | | information for 5 days (0-120 hours). | | | | | Final MGEX | Product reference: | | (expoermental) | Prange L., D. Arnold, R. Dach, E. Brockmann, | | products | M. Kalarus, S. Schaer, P. Stebler, A. Jaeggi (2023). | | | CODE final product series for the IGS. Published | | | by Astronomical Institute, University of Bern. | | | URL: http://www.aiub.unibe.ch/download/CODE_MGEX/yyyy;| | | DOI: 10.48350/185742. | | | | | | Files generated from three-day long-arc solutions: | | | COD0MGXFIN_yyyyddd0000_01D_05M_ORB.SP3.gz | | | (old: COMwwwwd.EPH.Z) | | | CODE MGEX GPS+GLONASS+Galileo+BDS+ | | | QZSS orbits | | | COD0MGXFIN_yyyyddd0000_01D_01D_ERP.ERP.gz | | | (old: COMwwwwd.ERP.Z) | | | CODE MGEX ERPs belonging to the MGEX | | | orbits | | | COD0MGXFIN_yyyyddd0000_01D_30S_CLK.CLK.gz | | | COD0MGXFIN_yyyyddd0000_01D_30S_CLK.CLK_V2.gz | | | (old: COMwwwwd_v3.CLK.Z) | | | (old: COMwwwwd.CLK.Z) | | | CODE MGEX clock product, clock RINEX | | | format (versions 3.04 and 2.00) | | | with a sampling of 30 sec. | | | for the GNSS satellite and reference | | | (station) clock corrections and | | | 5 minutes for all other for | | | all other station clock corrections | | | COD0MGXFIN_yyyyddd0000_01D_01D_OSB.BIA.gz | | | (old: COMwwwwd.BIA.Z) | | | CODE daily code and phase bias, | | | solution corresponding to the | | | above mentioned clock products, | | | bias SINEX format V1.00 | | | COD0MGXFIN_yyyyddd0000_01D_30S_ATT.OBX.gz | | | (old: COMwwwwd.OBX.Z) | | | Satellite attitude information | | | in ORBEX format | | | | | | | | Specialties in | - CODE has been generating its products from a | | CODE's analysis | rigorous combination of GPS, GLONASS and Galileo | | | observations. In this way, best possible | | | consistency of the orbit products is guaranteed. | | | - Uninterrupted POD for all transmitting GNSS | | | satellites, specifically for: | | | . brand new satellites | | | . satellites without any broadcast orbit information| | | . satellites marked unhealthy/unusable | | | . poorly observed (GLONASS) satellites | | | . (GPS) satellites being repositioned | | | - Elevation mask angle of 3 degrees used. | | | - Sophisticated ambiguity resolution scheme, already | | | including GLONASS ambiguity resolution (with | | | restrictions, specifically for baseline lengths | | | longer than 200 km), self-calibrating for GLONASS. | | | - Ambiguity verification scheme: resolved ambiguities | | | are checked in terms of compatibility, also in order| | | to detect unexpected quarter-cycle issues. | | | - GPS quarter-cycle phase bias issue: potentially | | | affected GPS ambiguities are banned from ambiguity | | | resolution. | | | - Continuous parametrization, particularly for EOP, | | | troposphere ZPD and horizontal gradient parameters, | | | ionosphere parameters, allowing for connection of | | | the parameters at day boundaries. | | | - For the three-day long-arc final solution the | | | continuity is only realized via constraints keeping | | | the realted parameters independent, in particular | | | SINEX file generation (compatibility to one-day | | | solutions from other analysis centers). | | | - IGS fiducial sites are automatically verified for | | | consistent datum definition for final, rapid, and | | | even the ultra-rapid processing. This is also true | | | with respect to all antenna-sharing fiducial sites. | | | - Inclusion of fast moving South Pole station AMU2. | | | - Generation of high-rate (5-sec) clock products. | | | - Generation of high-rate (1-hour) EOP results | | | (internally). | | | - Setup of GNSS satellite antenna PCV parameters | | | specific to each individual GPS, GLONASS and Galileo| | | satellite; corresponding patterns are not only | | | available for the ionosphere-free linear | | | combination but also for the geometry-free (L1-L2) | | | linear combination. | | | - A multi-GNSS-capable internal PCV file format is | | | used; receiver antenna PCV models specific to | | | GLONASS (or other) frequencies are applied. | | | - 3 terms of higher-order ionosphere (HOI) effects are| | | taken into account (based on CODE GIM & IGRF11SYN). | | | Scaling factor for 2nd and 3rd order HOI as well as | | | for ray bending for validation purposes and to | | | switch the parameter on or off | | | - Non-tidal loading deformations from Dill and Dobslaw| | | (2013) at observation level with scaling factors to | | | obtain solutions without applying such corrections | | | - Monitoring of various differential code biases | | | (DCBs), specifically: | | | . GPS/GLONASS P1-P2 satellite and receiver DCBs | | | . GPS/GLONASS P1-C1 and P2-C2 satellite DCBs | | | . biases crucial for GLONASS ambiguity resolution | | | Values are extracted from different data processing | | | steps and directly from the RINEX observation files | | | (where possible) | | | - Extensive monitoring of IGS data flow concerning: | | | . availability | | | . latency | | | . completeness | | | . consistency | | | - SINEX loop: COD SINEX results are routinely | | | imported and re-introduced. First extracted and | | | secondly re-produced station coordinate results are | | | cross-checked to the original analysis results (at | | | 0.01-mm level). The extracted list of fiducial | | | stations is used for this re-production. | | | - Provision of GNSS geocenter coordinates in SINEX. | | | - Production of GNSS rapid SINEX files containing | | | station coordinates and ERPs with a time resolution | | | of 6 hours is foreseen as a contribution for the | | | IERS inter-technique combination. | | | - Regular GNSS orbit validation using SLR data; CODE | | | acts as an AAC of the ILRS. | | | - The latest version of our steadily further | | | developed GNSS analysis software is employed for | | | operational analysis. | | | | | Computer platform | Week 1477: UBELIX: Linux, x86_64 | | | Week 1065: UBECX: SunOS | | | | | Last changes: | Week 2113: See IGSREPORT.27375 | | | Week 2072: See IGSMAIL.7832 | | Week 1691: See IGSREPORT.20913 | | | Week 1643: See IGSREPORT.19947 | | | Week 1632: See IGSREPORT.19702 | | | Week 1625: See IGSREPORT.19560 | | | Week 1619: See IGSREPORT.19411 | | | Week 1618: See IGSREPORT.19385 | | | Week 1604: See IGSREPORT.19068 and IGSMAIL.6287 | | | Week 1570: See IGSREPORT.18301 and IGSMAIL.6078 | | | Week 1542: See IGSREPORT.17667 and IGSMAIL.5970 | | | Week 1488: See IGSREPORT.16472 | | | Week 1477: See IGSREPORT.16225 and IGSMAIL.5771 | | | Week 1452: See IGSREPORT.15669/IGSREPORT.14622 | | | Week 1440: See IGSREPORT.15405 | | | Week 1439: See IGSREPORT.15403 | | | Week 1409: See IGSREPORT.14695 | | | Week 1406: See IGSREPORT.14622/IGSMAIL.5507 & .5518 | | | Week 1400: See IGSREPORT.14486 and IGSMAIL.5518 | | | Week 1367: See IGSREPORT.13669 | | | Week 1349: See IGSREPORT.13201 | | | Week 1328: See IGSREPORT.12706 | | | Week 1326: See IGSREPORT.12657 | | | Week 1321: See IGSREPORT.12569 and IGSMAIL.5151 | | | Week 1299: See IGSREPORT.12031 | | | Week 1282: See IGSREPORT.11617 | | | Week 1279: See IGSREPORT.11543 | | | Week 1255: See IGSMAIL.4913 | | | Week 1254: See IGSREPORT.10997 and IGLOSMAIL.963 | | | Week 1252: See IGSMAIL.4782 | | | Week 1242: See IGSREPORT.10752 | | | Week 1222: See IGSREPORT.10361 and | | | IGSMAIL.4474/IGLOSMAIL.770 | | | Week 1216: See IGSMAIL.4371/IGLOSMAIL.736 | | | Week 1191: See IGSREPORT.9756 and IGSMAIL.4162 | | | Week 1158: See IGSREPORT.9147 and IGSMAIL.3823 | | | Week 1143: See IGSREPORT.8868 | | | Week 1142: See IGSREPORT.8848 | | | Week 1135: See IGSREPORT.8710 | | | Week 1130: See IGSREPORT.8616 | | | Week 1128: See IGSREPORT.8577 | | | Week 1077: See IGSREPORT.7544 | | | Week 1065: See IGSREPORT.7279 | | | Week 1057: See IGSREPORT.7107 and IGSMAIL.2827 | | | Week 1021: See IGSREPORT.6351 | | | Week 0978: See IGSREPORT.5415 and IGSMAIL.2043 | | | Week 0947: See IGSREPORT.4698 and IGSMAIL.1829 | | | Week 0926: See IGSREPORT.4247 and IGSMAIL.1705 | | | Week 0873: See IGSREPORT.3056 | |---------------------------------------------------------------------------| | Preparation Date | 18-Aug-1996 | |---------------------------------------------------------------------------| | Modification Dates| 13-Mar-1998 | | | 12-Mar-2002/SS: Major revision and update | | | 13-Mar-2002/SS: JGM3 model up to degree 12 | | | 24-Oct-2002/SS: Typo concerning satellite antenna | | | offset value corrected | | | 28-May-2008/SS/RD: Major revision and update | | | 13-Oct-2010/SS/RD: Processing model update | | | 19-Dec-2012/SS: Major revision and update | | | 13-Feb-2015/RD: Consider most recent processing | | | updates | | | 08-Sep-2015/RD: Processing model update | | | 28-Jan-2019/RD: Adjust file descriptions | | | 11-Oct-2019/RD: Update regarding Galileo in | | | rapid/ultra-rapid processing | | | 14-Jan-2022/RD/AV: Processing model update | | | 21-Mar-2024/EB: Product update (long file names) | | | and model changes week 2238 (I20) | |---------------------------------------------------------------------------| | Effective Date for| 21-Mar-2024 | | Data Analysis | | ============================================================================= ============================================================================= | MEASUREMENT MODELS | |---------------------------------------------------------------------------| | Preprocessing | Phase preprocessing in a baseline by baseline mode | | | using triple-differences. In most cases, cycle slips | | | are fixed looking simultaneously at different linear | | | combinations of two frequencies. If a cycle slip cannot| | | be fixed reliably, bad data points are removed or new | | | ambiguities are set up. In addition, a data screening | | | step on the basis of weighted postfit residuals is | | | performed. Outliers are removed. | |---------------------------------------------------------------------------| | Basic Observables| GPS/GLONASS/Galileo(/BDS/QZSS) carrier phase; code only| | | used for receiver clock synchronization and MW | | | ambiguity resolution | | | Priorities for observation selection: | | | G L1 L1W L1C L1X | | | G L2 L2W L2C L2D L2P L2X L2S L2L | | | G C1 C1W C1C C1X | | | G C2 C2W C2C C2D C2P C2X C2S C2L | | | R L1 L1P L1C L1X | | | R L2 L2P L2C L2X | | | R C1 C1P C1C C1X | | | R C2 C2P C2C C2X | | | E L1 L1C L1X | | | E L2 L5Q L5X L5I | | | E C1 C1C C1X | | | E C2 C5Q C5X C5I | | | C L1 L2I L2X | | | C L2 L6I L6X | | | C C1 C2I C2X | | | C C2 C6I C6X | | | J L1 L1C L1X | | | J L2 L2L L2S L2X | | | J C1 C1C C1X | | | J C2 C2L C2S C2X | | |--------------------------------------------------------| | | Elevation angle cutoff : 3 degrees | | | Sampling rate : 3 minutes | | | Weighting : 6 mm for double-differenced | | | ionosphere-free phase | | | observations at zenith; | | | elevation-dependent weighting| | | function 1/cos(z)**2 | |---------------------------------------------------------------------------| | Modeled | Double differences, ionosphere-free linear combination | | observables | of two frequencies (see selection above) | |---------------------------------------------------------------------------| | Satellite antenna| SV-specific z-offsets & block-specific x- & y-offsets | | -center of mass | from IGS using file igs20_wwww.atx based on ITRF2020 | | offsets | | |---------------------------------------------------------------------------| | Satellite antenna| block-specific nadir angle-dependent "absolute" PCVs | | phase center | applied from file igs20_wwww.atx; no azimuth-dependent | | corrections | corrections applied | |---------------------------------------------------------------------------| | Satellite clock | 2nd order relativistic correction for non-zero | | corrections | orbit ellipticity (-2*R*V/c) applied | | | NOTE: Other dynamical relativistic effects under | | | Orbit Models | |---------------------------------------------------------------------------| | GPS attitude | Nominal (yaw-steering) attitude implemented | | model | whereas Kouba 2009 for eclipse | |---------------------------------------------------------------------------| | GLONASS attitude | Nominal (yaw-steering) attitude implemented | | model | whereas Dilssner et al. 2011 for eclipse | |---------------------------------------------------------------------------| | Galileo attitude | Nominal attitude according to GSA (2019) implemented. | | model | | |---------------------------------------------------------------------------| | RHC phase | Phase polarization effects applied (Wu et al., 1993) | | rotation corr. | | |---------------------------------------------------------------------------| | Ground antenna | "absolute" elevation- & azimuth-dependent (when | | phase center | available) PCVs & offsets from ARP applied from | | offsets & | file igs20_wwww.atx | | corrections | Receiver antenna models GNSS-specific correctiopns are | | | applied (as far as available). | | | Final: Observations without antenna corrections for the| | | related GNSS are ignored | |---------------------------------------------------------------------------| | Antenna radome | Calibration applied if given in file igs20_wwww.atx; | | calibrations | otherwise radome effect neglected (radome => NONE) | | | Final: Stations with a not calibrated antenna/radome | | | combination are ignored | |---------------------------------------------------------------------------| | Marker -> antenna| dN, dE, dU eccentricities from site logs applied to | | ARP eccentricity | compute station coordinates | | | Potential not-alignment to North is considered | |---------------------------------------------------------------------------| | Troposphere | ECMWF-based hydrostatic delay mapped with hydrostatic | | a priori model | VMF3. Coefficients from 3-hourly global grids. | | | GPT3/GMF3 in the rapid and ultra-rapid solution. | | | | | | Gradient model: none | |---------------------------------------------------------------------------| | Ionosphere | 1st order effect: eliminated by forming the | | | ionosphere-free dual frequency linear| | | combination. | | |--------------------------------------------------------| | | 2nd order effect: applied, IGRF13 implementation, TEC | | | from CODE global ionosphere model | | |--------------------------------------------------------| | | 3rd order effect: applied, TEC from CODE global | | | ionosphere model | | |--------------------------------------------------------| | | Other effects: ray bending applied, TEC from CODE | | | global ionosphere model | | | | | | GNSS-derived global ionosphere map | | | information is used to support | | | ambiguity resolution when using the | | | QIF strategy. | |---------------------------------------------------------------------------| | Tidal | Solid Earth tide : complete model from IERS | | displacements | Conventions 2010 | | | | | | Step 1: in-phase: degree 2 and 3 | | | Nominal h02 and l02 : 0.6078, 0.0847 (anela.)| | | Nominal h22 and l22 :-0.0006, 0.0002 | | | Nominal h3 and l3 : 0.292 , 0.015 | | | | | | out-of-phase: degree 2 only semi- and diurnal | | | diurnal: nominal hI, lI :-0.0025,-0.0007 | | | semi-di: nominal hI, lI :-0.0022,-0.0007 | | | | | | latitude dependence | | | diurnal: nominal l1 : 0.0012 | | | semi-di: nominal l1 : 0.0024 | | | | | | Step 2: in-phase: degree 2, diurnal | | | in-phase and out-of-phase: long-period tides | | |--------------------------------------------------------| | | Permanent tide : applied in tide model, | | | NOT included in site coordinates| | |--------------------------------------------------------| | | Solid Earth pole tide: applied (IERS 2010) | | |--------------------------------------------------------| | | Oceanic pole tide : not applied | | |--------------------------------------------------------| | | Ocean tide loading : IERS 2010, site-dependent amps | | | & phases from Bos & Scherneck | | | website for FES2014b tide model | | | NEU site displacements computed | | | using hardisp.f from D. Agnew | | |--------------------------------------------------------| | | Ocean tide geocenter : coeffs. corrected for center of | | | mass motion of whole Earth | | |--------------------------------------------------------| | | Atmospheric tides : S1+S2 tidal corrections from the| | | Vienna atmospheric pressure | | | model | |---------------------------------------------------------------------------| | Non-tidal | Atmospheric pressure : Non-tidal components from the | | loadings | GFZ loading model (Dill and | | | Dobslaw, 2013) with three | | | scaling factors per station (one| | | for each component) for | | | validation purposes. | | | The product files are generated | | | without considering the non- | | | tidal pressure loading by | | | forcing the scaling factors to | | | zero. | | |--------------------------------------------------------| | | Ocean bottom pressure: (as above) | | |--------------------------------------------------------| | | Surface hydrology : (as above) | | |--------------------------------------------------------| | | Other effects : none applied | |---------------------------------------------------------------------------| | Earth orientation| Ocean tidal: diurnal/semidiurnal variations in x,y, & | | variations | UT1 applied according to IERS 2010, Tables| | | 8.2a, 8.2b, 8.3a, 8.3b | | |--------------------------------------------------------| | | Atmosphere tidal: S1, S2, S3 tides not applied | | |--------------------------------------------------------| | | High-frequency nutation: applied according to IERS | | | 2010, Table 5.1a | | |--------------------------------------------------------| | | UT1 libration: applied according to IERS 2010, Table | | | 5.1.b | ============================================================================= ============================================================================= | REFERENCE FRAMES | |---------------------------------------------------------------------------| | Time argument | TDT | | | GPS time as given by observation epochs, which is | | | offset by only a fixed constant (approx.) from TT/TDT | |---------------------------------------------------------------------------| | Inertial | geocentric; mean equator and equinox of 2000 Jan 1 | | frame | at 12:00 (J2000.0) | |---------------------------------------------------------------------------| | Terrestrial | ITRF2020 reference frame realized through a set of | | frame | station coordinates and velocities given in the IGS | | | internal realization IGS20. | | | | | | Datum definition: | | | . 3 no-net translation conditions (only if geocenter | | | is estimated) | | | . 3 no-net rotation conditions | | | . geocenter coordinates constrained nominally to | | | zero values | | | IGS20 fiducial sites are selected as reference, if: | | | . horizontal deviation < 10 mm | | | . vertical deviation < 30 mm | |---------------------------------------------------------------------------| | Tracking | Ultra-rapid with about 100, rapid with 120 and final | | network | 270 stations per day are used. | | | Station selection is based on long time series, | | | contribution to existing reference frames, co-location | | | with other space-geodetic techniques, multi-GNSS- | | | capability (RINEX3 file delivery), all-in-view | | | tracking support for unhealthy satellites, and | | | availability of multi-GNSS antenna calibration values | |---------------------------------------------------------------------------| | Interconnection | Precession: IAU 2000 Precession Theory | | |--------------------------------------------------------| | (EOP parameter | Nutation: IAU 2000R06 Nutation Theory | | estimation is |--------------------------------------------------------| | below) | A priori EOPs: polar motion & UT1 from IERS C04 series | | | aligned to ITRF2020 | ============================================================================= ============================================================================= | ORBIT MODELS | |---------------------------------------------------------------------------| | Geopotential | EGM2008 model up to degree and order 12 (+C21+S21) | | (static) |--------------------------------------------------------| | | GM = 398600.4415 km**3/sec**2 | | |--------------------------------------------------------| | | AE = 6378.1363 km | |---------------------------------------------------------------------------| | Tidal variations | Solid Earth tides: applied according to IERS 2010 | | in geopotential |--------------------------------------------------------| | | Ocean tides: applied, FES2014b model | | |--------------------------------------------------------| | | Solid Earth pole tide: applied according to IERS 2010 | | |--------------------------------------------------------| | | Oceanic pole tide: applied according to IERS 2010 | |---------------------------------------------------------------------------| | Third-body | Sun, Moon, Jupiter, Venus, Mars as point masses | | |--------------------------------------------------------| | | Ephemeris: JPL DE421, Folkner et al. (2009) | | |--------------------------------------------------------| | | GMsun = 132712500000 km**3/sec**2 | | |--------------------------------------------------------| | | GMmoon = 4902.7890 km**3/sec**2 | |---------------------------------------------------------------------------| | Solar radiation | A priori: no a priori model for GPS, GLONASS | | pressure model | Galileo based on GSA 2019 optical | | (parameter | properties | | estimation is |--------------------------------------------------------| | below) | Earth shadow model: cylindrical shadow | | |--------------------------------------------------------| | | Earth albedo: numerical model according to | | | Rodriguez et al. (2012) | | |--------------------------------------------------------| | | Moon shadow model: umbra and penumbra | | |--------------------------------------------------------| | | Satellite attitude: nominal attitude | | |--------------------------------------------------------| | | Satellite antenna thrust: | | | Antenna thrust for GPS satellites according to | | | http://acc.igs.org/orbits/thrust-power.txt | | | Block I, II, IIA: 76 W | | | Block IIR: 85 W | | | Block IIR-M: 198 W (including M-code) | | | Block IIF: 249 W (including M-code) | | | SVN62 after 05 April 2011: 154 W (no M-code) | | | | | | Assumption for all GLONASS satellites: 100 W | | | | | | Assumption for Galileo satellites: IOV/FOC: 130/200 W | | |--------------------------------------------------------| | | Other forces: none applied | |---------------------------------------------------------------------------| | Relativistic | dynamical correction: applied according to IERS 2010, | | effects | eq. 10.12, Lense-Thirring & | | | geodesic precession neglected | | |--------------------------------------------------------| | | Gravitational time delay: applied according to | | | IERS 2010, eq. 11.17 | |---------------------------------------------------------------------------| | Numerical | Integration algorithms developed at AIUB by Gerhard | | Integration | Beutler (1990). Representation of the orbit by a | | | polynomial of degree 10 for 1 hour. | | |--------------------------------------------------------| | | Integration step: 1 hour | | |--------------------------------------------------------| | | Starter procedure: no special starter procedure needed | | |--------------------------------------------------------| | | Arc length: 72 hours for long-arc solutions | ============================================================================= ============================================================================= | ESTIMATED PARAMETERS (& APRIORI VALUES & CONSTRAINTS) | |---------------------------------------------------------------------------| | Adjustment | Weighted least-squares algorithms | | method | | |---------------------------------------------------------------------------| | Data Span | Long-arc solutions include the data from three days, | | | combined on normal equation level. | | | Early rapid/ultra-rapid: products are extracted from | | | the last day of the triple. | | | Final rapid: middle part of a long-arc solution through| | | two rapid and a subsequent ultra-rapid solution | | | Final: satellite orbits and troposphere | | | parameters are extracted from the middle day | |---------------------------------------------------------------------------| | Station | All station coordinates are adjusted with minimum | | coordinates | constraints, see above. | |---------------------------------------------------------------------------| | Satellite clocks | Not applicable for double difference processing | |---------------------------------------------------------------------------| | Receiver clocks | Not applicable for double difference processing | |---------------------------------------------------------------------------| | Orbital | 6 Keplerian elements plus 9 solar radiation parameters | | parameters | at start of arc; no a priori sigmas used. | | | Estimated RPR parameters (see Arnold et al., 2015): | | | - Constants in D-, Y- and X-direction | | | - Periodic 1 per rev. terms in X-direction | | | - Periodic 2 per rev. terms in D-direction | | | - Periodic 1 per rev. sine terms in D-direction | | | for Galileo in eclipse (see Sidorov et al., 2020) | | | A priori orbits are from a previous processing run | | | or from the CODE rapid orbit solution. | | | Pseudo-stochastic orbit parameters (small velocity | | | changes), every 12 hours for rapid nd MGEX but orbit | | | midnight in the final solution constrained to: | | | . 1.E-6 m/sec in radial | | | . 1.E-5 m/sec in along-track | | | . 1.E-8 m/sec in out-of-plane | |---------------------------------------------------------------------------| | Satellite | Not estimated | | attitude | | |---------------------------------------------------------------------------| | Troposphere | Zenith delay: estimated for each station in intervals | | | of 2 hours. Loose relative constraints of| | | 5 m are applied. Piece-wise, linear | | | parametrization, allowing for connection | | | of the parameters at day boundaries. | | |--------------------------------------------------------| | | Zenith delay epochs: every two hours starting at | | | midnight | | |--------------------------------------------------------| | | Mapping function: wet VMF3 for final; GMF3 for rapid | | |--------------------------------------------------------| | | Gradients: pairs of horizontal delay gradient | | | parameters are estimated in N-S and E-W | | | direction for each station in intervals of | | | 24 hours. Loose relative constraints of | | | 5 m are applied. Piece-wise, linear | | | parametrization, allowing for connection of | | | the parameters at day boundaries. | | | Details about the gradient model can be | | | found in Rothacher et al. (1997). | | | Refined gradient model used, see Chen and | | | Herring (1997). | |---------------------------------------------------------------------------| | Ionospheric | Not estimated in ionosphere-free analyses | | correction | | | | One scaling factor for 2nd and 3rd order terms and ray | | | bending is setup to switch the components on or off | | | on normal equation level. | | | The products are generated with considering all three | | | correction components. | |---------------------------------------------------------------------------| | Ambiguity | Ambiguities are resolved in a baseline-by-baseline | | | mode performing the following steps: | | | . Melbourne-Wuebbena approach (< 6000 km) | | | . Quasi-Ionosphere-Free (QIF) approach (< 2000 km) | | | (also for GLONASS, same frequencies) | | | . Phase-based widelane/narrowlane method (< 200 km) | | | (also for GLONASS, no restrictions) | | | . Direct L1/L2 method, also for GLONASS (< 20 km) | | | (also for GLONASS, no restrictions) | | | GNSS-derived global ionosphere map information is used | | | to support the code-less methods. | |---------------------------------------------------------------------------| | Earth Orient. | X- and Y-pole coordinates, and UT1-UTC are represented | | Parameters (EOP) | each with piece-wise linear polynomials which are | | | continuous in time realized by constraints removable | | | on SINEX level. UT1-UTC is fixed to the a priori | | | value at the beginning of the first day. No further | | | a priori sigmas are used. | | | | | | All reported CODE EOP solutions do include a subdaily | | | EOP model (see above). The estimates therefore | | | correspond to daily averages on top of the introduced | | | a priori model. | | | | | | High-rate (1-hour) X-, Y- and UT1-UTC estimates are | | | also generated in a special 3-day solution. | |---------------------------------------------------------------------------| | Other | Center of mass coordinates: | | parameters | | | | Center of mass, or geocenter coordinate parameters are | | | commonly set up as part of each solution. The related | | | parameters are usually heavily constrained to zero | | | values. Additional computations on the normal equation | | | level are made regularly in order to retrieve 1-day, | | | 3-day, as well as weekly GNSS geocenter coordinates in | | | the current ITRF. | | | | | | GNSS satellite phase center offsets and patterns: | | | | | | Corresponding parameters are commonly set up as part | | | of each final solution for each individual GNSS | | | satellite. The related parameters are again removed | | | from the normal equation before the solution is | | | computed to fix parameters to the nominal values (as | | | defined by the IGS20 PCV model). Such GNSS PCV | | | parameters are available for the ionosphere-free as | | | well as the geometry-free linear combination. | | | | | | GNSS-bias parameter: | | | | | | An extra set of six parameters is set up for each | | | GLONASS and Galileo observing station to characterize: | | | - one GLONASS-GPS/Gallileo-GPS receiver antenna offset | | | veector (three components) and | | | - one GLONASS-GPS/Gallileo-GPS ZPD ZPD and gradient | | | troposphere bias | | | These biases are estimated internally on a weekly basis| | | together with the station coordinates. | | | | | | Loadiung scaling factors: see above | | | | ============================================================================= ============================================================================= | REFERENCES | | | | Arnold, D., M. Meindl, G. Beutler, R. Dach, S. Schaer, S. Lutz, L. Prange,| | K. Sosnica, L. Mervart, A. Jäggi (2015), CODE's new solar radiation | | pressure model for GNSS orbit determination. | | Journal of Geodesy, vol. 89(8), pp. 775-791, 10.1007/s00190-015-0814-4 | | | | Bassiri, S., and G.A. Hajj (1993), Higher-order ionospheric effects on | | Global Positioning System observables and means of modeling them, | | Manuscripta Geodaetica, vol. 18, pp. 280-289 | | | | Beutler, G. (1990), Numerische Integration gewoehnlicher Differential- | | gleichungssysteme: Prinzipien und Algorithmen. Mitteilungen der | | Satelliten-Beobachtungsstation Zimmerwald, No. 23, Druckerei der | | Universitaet Bern | | | | Beutler, G., E. Brockmann, W. Gurtner, U. Hugentobler, L. Mervart, and | | M. Rothacher (1994), Extended Orbit Modeling Techniques at the CODE | | Processing Center of the International GPS Service for Geodynamics (IGS)| | Theory and Initial Results, Manuscripta Geodaetica, vol. 19, pp. 367-386| | | | Boehm, J., B. Werl, and H. 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Ostini (2009), GNSS processing at CODE: status | | report, Journal of Geodesy, vol. 83(3-4), pp. 353-366 | | | | Dach, R., S. Lutz, P. Walser, P. Fridez (Eds); 2015: Bernese GNSS Software| | Version 5.2. User manual, Astronomical Institute, University of Bern, | | Bern Open Publishing. DOI: 10.7892/boris.72297; ISBN: 978-3-906813-05-9.| | URL: ftp://ftp.aiub.unibe.ch/BERN52/DOCU/DOCU52.pdf | | | ! Dill, R. and H. Dobslaw (2013): ! Numerical simulations of global-scale | | high-resolution hydrological crustal deformations. J. Geophys. Res. | | Solid earth 118, doi:10.1002/jgrb.50353. | | | | Dilssner, F., T. Springer, G. Gienger, J. Dow (2011), The GLONASS-M | | satellite yaw-attitude model. Adv. Space Res., vol. 47(1), pp. 160-171, | | doi: 10.1016/j.asr.2010.09.007 | | | | Alken, P., Thebault, E., Beggan, C.D. et al. (2021), International | | Geomagnetic Reference Field: the thirteenth generation. 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Factor (2012).The development| | and evaluation of the Earth Gravitational Model 2008 (EGM2008), Journal | | of Geophysical Research, vol. 117, B04406, doi:10.1029/2011JB008916 | | | | Rodriguez-Solano, C. J., U. Hugentobler, P. Steigenberger (2012) Impact of| | albedo radiation on GPS satellites; in: S.C. Kenyon, M.C. Pacino, | | U.J. Marti, (eds.) Geodesy for Planet Earth, IAG Symposia, Vol. 136, | | pp. 113-119, Springer, DOI: 10.1007/978-3-642-20338-1_14 | | | | Rothacher, M., T.A. Springer, S. Schaer, G. Beutler (1997), Processing | | Strategies for Regional GPS Networks, IAG Symposia, vol. 118, pp. 93-100| | | | Folkner, W.M., J.G. Williams, D.H. Boggs (2009), The Planetary and Lunar | | Ephemeris DE421, IPN Progress Report 42-178 | | | | Schaer, S. (1999), Mapping and Predicting the Earth's Ionosphere Using the| | Global Positioning System, Geodaetisch-geophysikalische Arbeiten in der | | Schweiz, vol. 59 | | | | Sidorov, D., R. Dach, B. Polle, L. Prange, A. Jäggi (2020), Adopting the | | empirical CODE orbit model to Galileo satellites, Adv. Space Res., | | vol. 66(12), pp. 2799-2811, doi:10.1016/j.asr.2020.05.028 | | | | Wu, J.T., S.C. Wu, G.A. Hajj, W.I. Bertiger, S.M. Lichten (1993), | | Effects of antenna orientation on GPS carrier phase. Manuscripta | | Geodaetica, vol. 18, pp. 91-98 | | | =============================================================================