Author: AC Coordinator / NOAA NGS sum-file Version 2.0 Rapid IGS Orbit Combination - Week 1501 Day: 4 (Oct 16, 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: igr15014.sp3 IGR GPS ephemeris in SP3 format. igr15014.clk IGR GPS satellite and station clocks in RINEX format. igr15014.cls IGR GPS clock combination summary report. igr15014.erp Earth Rotation Parameters (ERP) and their rates as well as Universal Time (UT1-UTC) and Length Of Day (LOD) associated with IGS ephemerides. igr15014.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 ----+--------+--------------- 4 | ESA | CHAT JOZE KOUR SYOG 4 | GFZ | 7 BOR1 4 | JPL | DAEJ NICO 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 ----+------------+---------- G29 | 2008_10_16 | 2008129 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 ----+--------+--------------- 4 | USN | 7 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 1.1501.4 GPS week: 1501 Day: 4 MJD: 54755.000 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| -130 23 114 -340 112 -1935-24.98 941 941 | -402 494 2813 5142 cod 133| 0 2 5 14 21 -67 -.29 12 12 | -742 524 23 105 emr 45| -4 -6 0 -43 -82 -1 .29 15 15 | -213 -3768 12 102 esa 94| 0 -1 1 21 26 18 .17 11 11 | -1531 1842 16 96 gfz 93| 0 4 -6 -43 -14 -28 -.20 14 14 | 17 -202 20 109 iga n/a| 0 2 2 12 -16 223 -.11 9 9 | -410 502 99 152 igu n/a| 0 3 -2 -4 -245 -232 -.12 26 26 | -208 -3095 2767 5450 jpl 45| -3 -1 0 9 21 41 .35 20 19 | 2250 -3992 21 131 ngs 99| 3 0 0 -90 -57 28 -.23 16 14 | -433 613 2253 4408 sio 70| 4 -1 2 86 33 60 -.17 19 18 | 0 0 0 0 usn 45| -4 2 -9 202 123 -2 -.06 42 32 | 1188 -3928 92 1825 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 2.1501.4 GPS week: 1501 Day: 4 MJD: 54755.000 Weighted Average PRN | brd cod emr esa gfz iga igu jpl ngs sio usn IGR | ------+-------------------------------------------------------------+ X1 | 2260 17 --- --- --- --- --- --- --- --- 72 33 | 2 | 411 11 25 14 19 9 28 29 20 14 34 7 | 3 | 816 6 10 8 11 9 32 13 17 21 36 5 | 4 | 763 11 14 8 18 9 16 14 19 13 32 5 | 5 | 991 11 10 7 12 8 37 12 15 15 39 5 | 6 | 949 6 11 8 13 7 31 12 11 17 32 4 | 7 | 1393 13 16 11 14 11 19 18 13 16 123 6 | 8 | 1027 10 14 8 10 7 15 17 10 14 32 5 | 9 | 542 14 15 9 16 9 30 15 15 29 33 6 | 10 | 833 10 13 6 10 7 31 23 14 14 28 5 | 11E | 1025 8 12 11 13 8 31 22 17 18 32 5 | 12 | 810 15 16 15 11 10 20 34 18 23 52 8 | 13 | 715 11 17 11 15 9 23 18 13 16 29 5 | 14 | 833 12 16 15 13 10 20 22 19 17 38 6 | X15 | 904 10 21 15 17 11 21 --- 19 --- 52 8 | 16 | 1311 8 13 12 10 9 17 18 12 19 35 5 | 17 | 760 16 15 14 21 13 26 24 21 22 35 7 | 18 | 698 11 18 13 15 11 20 23 17 19 51 7 | 19 | 441 13 17 15 16 11 20 20 16 23 37 6 | 20 | 745 13 14 14 18 11 34 24 14 17 36 6 | 21 | 1051 14 22 14 10 10 28 23 18 24 48 7 | 22 | 336 12 17 14 17 10 24 23 15 18 40 6 | 23 | 829 12 20 15 11 10 27 20 13 17 30 6 | 24 | 1334 14 18 11 14 11 22 15 16 23 28 6 | 25 | 1346 11 12 9 14 7 19 14 13 15 25 5 | 26 | 634 11 16 10 14 8 23 10 19 22 31 5 | 27 | 1349 15 12 7 12 6 28 13 13 17 23 5 | 28 | 1348 12 13 13 15 7 36 20 16 16 30 5 | X29 |>>>>> 7 --- --- --- --- --- --- --- --- --- 0 | 30 | 1278 11 9 7 15 7 31 12 16 14 26 4 | 31 | 573 10 18 13 18 9 30 26 14 32 32 7 | 32 | 670 8 16 7 9 7 24 18 15 18 47 5 | ------+-------------------------------------------------------------+ RMS | 941 12 15 11 14 9 26 20 16 19 42 | WRMS | 941 12 15 11 14 9 26 19 14 18 32 | MEDI | 833 11 15 11 14 9 24 18 15 17 34 | 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 3.1501.4 GPS week: 1501 Day: 4 MJD: 54755.0 CENT| CLK EPO | BRUS | TOW2 | WILL | ----+----------+-------------------+-------------------+-------------------+ cod | cod 3021 | 9 18 33 | ---- ---- ---- | 7 6 16 | emr | emr 2874 | 10 17 31 | ---- ---- ---- | 11 10 32 | esa | esa 2880 | 10 18 32 | ---- ---- ---- | 8 8 24 | gfz | gfz 2870 | 11 18 32 | ---- ---- ---- | 13 13 33 | igr | igr 2874 | 10 17 31 | ---- ---- ---- | 10 9 27 | jpl | jpl 2783 | 11 14 33 | ---- ---- ---- | 11 11 33 | 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 4.1501.4 GPS week: 1501 Day: 4 MJD: 54755.500 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 | -34 -35 -19 10 9 | 11 13 emr uuuuu | 87 59 -373 -102 -19 | 65 65 esa uuuuu | -66 -46 292 -256 -7 | 26 27 gfz uuuuu | 0 39 -34 57 10 | 15 17 iga xxxxx | 1 -21 96 -44 19 | 4 6 igu xxxxx | 238 -36 313 78 7 | -11 37 jpl uuuuu | -3 -38 -285 99 -11 | 1 10 ngs uuuuu | 67 81 402 153 36 | 18 25 sio uuuuu | -14 -52 -178 270 -22 | 85 86 usn uuuuu | 19 2 148 -21 -40 | 35 50