Author: AC Coordinator / NOAA NGS sum-file Version 2.0 Rapid IGS Orbit Combination - Week 1534 Day: 2 (Jun 02, 2009) 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: igr15342.sp3 IGR GPS ephemeris in SP3 format. igr15342.clk IGR GPS satellite and station clocks in RINEX format. igr15342.cls IGR GPS clock combination summary report. igr15342.erp Earth Rotation Parameters (ERP) and their rates as well as Universal Time (UT1-UTC) and Length Of Day (LOD) associated with IGS ephemerides. igr15342.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 ----+--------+--------------- 2 | ALL | 1 2 | COD | 8 9 10 2 | EMR | WTZR 2 | ESA | 8 9 10 SEY1 SYOG TSKB 2 | GFZ | 18 20 22 27 32 BRUS CHUR SHAO 2 | JPL | 32 5. New clock offsets and drifts were estimated for centres showing reference clock resets. Note that only the largest clock offset and drift are output to the summary file. However, the clock combination and the listed RMS include all the clock segments. In summary, the following clock shifts/resets were noticed and accounted for: Day | Centre | Time | Jump ----+--------+--------+------------- 2 | GFZ | ~21:15 | ~ -0.31 ns 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 ----+--------+--------------- 2 | EMR | 1 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 1.1534.2 GPS week: 1534 Day: 2 MJD: 54984.000 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| 1 42 -6 2163 -1962 -3784-25.43 865 865 | 226 -169 1982 4426 cod 133| 2 -1 7 43 8 -43 -.26 13 13 | -175 -666 21 76 emr 45| 0 5 -2 -73 -55 -11 .21 19 19 | 3997 -2621 15 71 esa 95| -2 0 -1 30 -1 41 .37 9 9 | 482 -1979 13 75 gfz 88| 0 -2 2 21 0 9 -.07 18 18 | -999999 81728 23 84 iga n/a| 1 0 0 11 4 -84 -.03 9 7 | 2 92 28 91 igu n/a| 2 0 -1 -463 -135 -360 -.14 77 59 | 103 -625 1749 3211 jpl 80| 4 1 -6 -21 44 50 .34 18 16 | 1211 -2218 13 74 ngs 153| 0 0 0 0 -12 -91 -.34 11 10 | 217 -192 1858 4009 sio 63| 0 -1 0 3 14 118 -.24 17 16 | 0 0 0 0 usn 35| 1 -2 0 -91 -10 -90 -.05 18 17 | -615 -701 53 116 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 2.1534.2 GPS week: 1534 Day: 2 MJD: 54984.000 Weighted Average PRN | brd cod emr esa gfz iga igu jpl ngs sio usn IGR | ------+-------------------------------------------------------------+ X1 |86240 39 190 --- --- --- --- --- 34 --- --- 36 | 2 | 272 14 23 10 12 7 22 25 9 17 16 5 | 3 | 1360 13 9 10 15 6 21 6 6 16 11 4 | 4 | 955 13 21 8 20 8 29 16 9 20 26 6 | X5 | 1565 18 --- --- --- 29 --- --- 15 --- --- 16 | 6 | 932 11 9 8 15 8 98 6 6 14 12 4 | 7E | 466 11 17 12 14 7 24 19 14 20 11 5 | 8E | 855 12 18 9 19 9 33 18 13 20 22 6 | 9E | 851 18 26 13 59 16 127 25 12 16 24 10 | 10E | 820 12 16 7 17 7 28 17 11 17 15 5 | 11 | 880 9 17 10 11 7 32 16 10 15 22 5 | 12 | 269 15 21 8 12 8 34 22 10 17 18 5 | 13 | 740 11 19 8 11 7 19 24 10 14 18 5 | 14 | 910 12 21 8 12 7 57 17 12 16 15 5 | 15 | 845 10 20 11 17 6 14 25 14 21 19 6 | 16 | 774 14 18 8 16 8 30 22 13 10 17 5 | 17 | 458 11 13 7 16 6 20 13 11 16 31 5 | 18E | 697 10 16 7 16 8 55 20 13 22 9 5 | 19 | 185 11 14 10 14 5 17 14 9 17 18 4 | 20E | 881 9 20 12 13 8 12 18 12 14 21 5 | 21 | 857 8 21 8 10 5 19 17 10 14 13 4 | 22E | 720 11 20 8 10 13 19 20 12 16 11 5 | 23 | 331 20 23 11 17 7 21 21 10 11 23 6 | 24 | 1093 9 14 6 9 6 29 13 7 13 16 4 | 25 | 695 30 16 11 13 21 234 23 10 23 15 7 | 26 | 821 12 17 5 11 7 36 12 9 14 16 4 | 27E | 1560 16 28 13 17 12 198 21 14 20 26 7 | 28 | 890 11 23 9 19 7 17 21 13 14 20 6 | 29 | 1160 6 14 8 22 5 22 13 12 17 16 5 | 30 | 850 12 12 8 10 9 28 13 8 11 17 4 | 31E | 1207 11 20 10 15 8 27 14 12 21 16 5 | 32E | 942 15 27 11 14 11 199 22 15 20 16 6 | ------+-------------------------------------------------------------+ RMS | 865 13 19 9 18 9 77 18 11 17 18 | WRMS | 865 13 19 9 18 7 59 16 10 16 17 | MEDI | 851 12 19 8 14 7 28 18 11 16 16 | 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 3.1534.2 GPS week: 1534 Day: 2 MJD: 54984.0 CENT| CLK EPO | BRUS | TOW2 | WILL | ----+----------+-------------------+-------------------+-------------------+ cod | cod 3072 | 8 7 18 | 4 10 26 | 6 7 26 | emr | emr 2950 | 11 10 22 | 7 11 30 | 7 10 24 | esa | esa 2880 | 8 7 21 | 4 8 23 | 6 6 20 | gfz | gfz 2839 | 9 9 25 | 12 15 45 | 6 7 24 | igr | igr 2822 | 8 7 20 | 4 9 24 | 6 9 23 | jpl | jpl 2861 | 9 9 21 | 11 10 55 | 5 8 18 | 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 4.1534.2 GPS week: 1534 Day: 2 MJD: 54984.500 AC LOD AC LOD CENT FLAG | Xpole Ypole Xrt Yrt LOD | BIAS BIAS RMS | [uas] [uas] [uas/d] [uas/d] [us]| [us] [us] ------------+----------------------------------------+------------------ cod xxxxx | -29 -58 5 -201 -4 | 0 20 emr uuuuu | 109 31 382 -18 -15 | 36 49 esa uuuuu | -5 -35 21 78 -3 | 13 27 gfz uuuuu | -29 -20 -54 -239 7 | 20 31 iga xxxxx | -17 -35 89 -45 3 | -4 19 igu xxxxx | 127 434 219 350 -54 | -21 46 jpl uuuuu | -55 26 -151 -136 -7 | -9 35 ngs uuuuu | 30 6 -140 305 6 | 2 16 sio uuuuu | -51 -13 -84 -166 -26 | 54 63 usn uuuuu | -13 51 149 -137 -3 | 6 18