Author: AC Coordinator / NOAA NGS sum-file Version 2.0 Rapid IGS Orbit Combination - Week 1503 Day: 3 (Oct 29, 2008) Contacts: J. Ray (jim.ray@noaa.gov), J. Griffiths (jake.griffiths@noaa.gov) COMBINATION STRATEGY: --------------------- For a complete description of the combination strategy along with all tables and statistics, please refer to the IGS Final Combination reports posted on CDDIS within 13 days after the end of the GPS week. PRODUCT FILES: -------------- The Rapid Orbit files generated and uploaded into CDDIS @ NASA/GSFC are: igr15033.sp3 IGR GPS ephemeris in SP3 format. igr15033.clk IGR GPS satellite and station clocks in RINEX format. igr15033.cls IGR GPS clock combination summary report. igr15033.erp Earth Rotation Parameters (ERP) and their rates as well as Universal Time (UT1-UTC) and Length Of Day (LOD) associated with IGS ephemerides. igr15033.sum Combination summary report. REMARKS concerning the IGR Orbit Combination: --------------------------------------------- 1. Broadcast ("brd") orbits/clocks are included in the combination for statistics only. However broadcast clock corrections are used for clock alignment to GPS time and centre clock weight determination purposes. 2. The following center solutions (orbits/clocks) were excluded from the combination but kept for statistics: -> Centre: IGA IGU 3. The following centre clock solutions, which provide broadcast clock corrections, were excluded from the combination but kept in the combination statistics: -> Centre: NGS 4. The following clock solutions were excluded from the combination because they were biasing the combined clock solutions (clock shifts/outliers) but were kept for the RMS computation. All clocks from USN. Day | Centre | PRN/STA list ----+--------+--------------- 3 | EMR | 4 24 HARB YELL 3 | ESA | CHUR NRIL 3 | GFZ | 7 3 | JPL | 4 AREQ HARB SANT 5. The following table lists all maneuvered satellites. The solutions from COD and ESA, which modeled the maneuver, are used for combination. An associated accuracy code of 0 (unknown) is given if only one AC is left (no redundancy). PRN | Date | Ref. NANU ----+------------+---------- G02 | 2008_10_29 | 2008136 6. The following orbit solutions were excluded from the combination because they were biasing the weighted average. They were still used for statistics computation unless all centres were excluded for the problem satellites in which case they were simply eliminated from the combination and statistics. The following table lists the exclusions: Day | Centre | PRN list ----+--------+--------------- 3 | NGS | 1 3 | USN | 1 31 32 7. Starting on 5-Nov-2006 (GPS Week 1400-0, MJD 54044) all IGS products, including the IGS combined orbits, are based on the IGS realization of the ITRF2005 reference frame (IGS05). For more information see IGSMAIL #5447. 8. Starting on 5-Nov-2000 (GPS Week 1087-0; mjd=51853) all IGS clock products are based on the new clock combination scheme which uses the the clock RINEX files as input if available, otherwise SP3 clocks are used. The navigation solution is still based on the SP3 clocks but this will soon adopt the clock RINEX files as well. 9. Starting on 5-Nov-2006 (GPS Week 1400, day 0, MJD 54044) the absolute antenna model is introduced (IGSMAIL #5272). The antenna phase center offsets and phase center variations are given in the file: ftp://igscb.jpl.nasa.gov/pub/station/general/igs05.atx ORBIT COMBINATION AND EVALUATION STATISTICS: -------------------------------------------- Table 1: Daily transformation of each centre to the combined IGR orbit and clocks (iga is the 24h adjusted part of Ultra Rapid, igu is the 24h predicted part of Ultra Rapid). WRMS - RMS weighted by the centres SP3 header accuracy codes. STA - Number of stations in the daily solutions. Table 1.1503.3 GPS week: 1503 Day: 3 MJD: 54768.000 CENT STA| DX DY DZ RX RY RZ SCL RMS WRMS| TOFT TDRFT SDEV RMS | [mm] [mm] [mm] [uas] [uas] [uas] [ppb] [mm] [mm]| [ps] [ps/d] [ps] [ps] --------+----------------------------------------------------+------------------------------ brd n/a| 20 -19 -3 -2151 -2378 -467-23.94 1038 1038 | 21 -18 2368 3905 cod 129| 1 1 0 -25 -47 9 -.32 12 12 | -894 1083 26 147 emr 45| -2 -3 2 -84 -68 10 .34 15 15 | 1583 446 14 127 esa 95| 0 0 -3 47 59 -28 .19 12 12 | -1180 932 19 134 gfz 87| 0 2 0 -7 6 17 -.14 17 17 | 28 -50 23 117 iga n/a| 2 2 -1 -48 -14 161 -.09 10 10 | -1 -1 40 187 igu n/a| 1 2 -2 -132 84 431 -.12 45 41 | 335 -1866 3060 5905 jpl 45| -2 0 4 11 -20 -110 .40 20 20 | 3429 704 25 161 ngs 96| 0 -1 -1 3 41 31 -.42 17 15 | 30 -35 2197 3643 sio 68| 2 1 2 61 1 84 -.15 23 23 | 0 0 0 0 usn 43| -3 -2 -13 80 151 14 -.10 94 33 | 2153 732 106 1936 Table 2: Daily fit for each satellite and each centre resulting from weighted average combination. The last column gives the IGR resulting satellite accuracy measures found in the IGS SP3 header. Eclipsing satellites are flagged with "E" (or "M" for moon) beside the PRN number. "X" stands for excluded from RMS, WRMS and MEDI-combination statistics but included in IGU Units: mm Table 2.1503.3 GPS week: 1503 Day: 3 MJD: 54768.000 Weighted Average PRN | brd cod emr esa gfz iga igu jpl ngs sio usn IGR | ------+-------------------------------------------------------------+ X1 | 1058 6 --- --- --- --- --- --- 2641 --- 278 0 | X2E |>>>>> 6 --- --- --- --- --- --- --- --- --- 0 | 3 | 746 6 10 9 13 8 84 14 15 18 45 5 | 4E | 1566 12 21 16 21 11 54 18 28 31 27 8 | 5 | 642 8 12 8 15 6 39 12 10 16 28 4 | 6 | 848 6 11 7 12 6 35 12 14 18 36 5 | 7 | 1208 13 18 14 14 8 38 16 14 28 37 6 | 8 | 1089 13 11 9 16 8 23 15 18 17 30 5 | 9 | 1566 15 22 13 13 9 22 18 18 41 25 7 | 10 | 1223 8 12 11 14 12 24 18 15 15 33 5 | 11E | 999 11 18 12 14 11 58 22 13 20 44 6 | 12 | 588 10 12 10 13 9 40 30 10 18 39 6 | 13 | 916 13 15 15 15 9 44 19 14 15 38 6 | 14 | 766 12 15 13 16 9 21 24 18 20 36 6 | 15 | 780 13 18 12 19 12 20 26 20 20 26 7 | 16 | 803 10 11 11 15 6 54 14 12 17 37 5 | 17 | 747 15 16 15 21 9 31 20 16 27 34 7 | 18 | 845 13 17 19 19 11 27 23 18 26 40 7 | 19 | 877 13 17 14 22 13 61 21 17 20 32 6 | 20 | 928 17 16 16 15 10 18 29 13 22 41 7 | 21E | 794 11 14 13 12 11 23 20 19 24 53 7 | 22 | 503 13 17 14 19 9 29 22 18 15 51 7 | 23 | 1395 13 16 16 14 11 49 19 17 19 44 6 | 24E | 1438 13 19 14 20 14 124 18 27 28 45 8 | 25E | 2222 13 19 8 17 13 38 15 20 26 21 6 | 26 | 508 10 13 8 19 10 26 16 12 20 30 5 | 27 | 1328 11 13 8 17 7 24 16 16 23 28 5 | 28 | 867 10 11 13 13 7 49 22 17 14 38 6 | 29 | 377 19 18 16 20 14 45 28 21 37 37 8 | 30 | 879 7 13 8 20 8 33 10 13 18 21 5 | 31 | 829 8 16 12 17 8 19 21 18 26 201 6 | 32 | 646 7 15 8 16 6 21 28 10 11 434 6 | ------+-------------------------------------------------------------+ RMS | 1037 12 15 12 17 10 45 20 17 23 94 | WRMS | 1037 12 15 12 17 10 41 20 15 23 33 | MEDI | 867 11 15 12 16 9 33 19 17 20 37 | Table 3: Daily Precise Navigation Summary using the corresponding Centre orbit positions and satellite clock corrections at 15 min intervals. Each line gives the daily station RMS w.r.t. the estimated coordinates for the Latitude, Longitude and Height components. CLK - Satellite clocks used. EPO - Number of satellite clock epochs available for that day. Units: mm Table 3.1503.3 GPS week: 1503 Day: 3 MJD: 54768.0 CENT| CLK EPO | BRUS | WILL | ----+----------+-------------------+-------------------+ cod | cod 3066 | 8 7 20 | 5 6 16 | emr | emr 2872 | 12 11 28 | 8 8 20 | esa | esa 2880 | 10 8 28 | 6 7 18 | gfz | gfz 2864 | 12 12 26 | 10 8 28 | igr | igr 2875 | 11 10 26 | 6 6 18 | jpl | jpl 2871 | 11 12 29 | 11 11 25 | Table 4: Earth Orientation Parameters daily summary. Daily Centre ERP, ERP Rates and LOD differences with respect to IGR combined values. Xpole,Xrt: x pole and x pole rate Ypole,Yrt: y pole and y pole rate LOD : Length Of Day AC LOD BIAS : 21-day mean LOD bias with respect to Bulletin A AC LOD BIAS RMS: RMS of AC LOD BIAS FLAG: "u" (used), "x" (excluded), "-" (no submission) for Xpole, Ypole, Xrt, Yrt and LOD A star ("*") beside the AC name indicates that AC LOD values were derived from AC UT1-UTC values. Table 4.1503.3 GPS week: 1503 Day: 3 MJD: 54768.500 AC LOD AC LOD CENT FLAG | Xpole Ypole Xrt Yrt LOD | BIAS BIAS RMS | [uas] [uas] [uas/d] [uas/d] [us]| [us] [us] ------------+----------------------------------------+------------------ cod uuuuu | 33 -6 100 -138 6 | 4 20 emr uuuuu | 41 145 -267 62 1 | 42 49 esa uuuuu | -63 -82 93 8 -5 | 15 26 gfz uuuuu | -28 1 -3 -72 4 | 13 24 iga xxxxx | 9 9 5 -180 11 | -4 20 igu xxxxx | -193 -33 -325 -395 -93 | -10 43 jpl uuuuu | 58 -42 235 288 -1 | -14 26 ngs uuuuu | -44 -36 -148 -97 -13 | 14 24 sio uuuuu | 6 8 -70 -146 17 | 62 67 usn uuuuu | 29 39 78 408 7 | 16 44