Author: AC Coordinator / NOAA NGS sum-file Version 2.0 Rapid IGS Orbit Combination - Week 1508 Day: 2 (Dec 02, 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: igr15082.sp3 IGR GPS ephemeris in SP3 format. igr15082.clk IGR GPS satellite and station clocks in RINEX format. igr15082.cls IGR GPS clock combination summary report. igr15082.erp Earth Rotation Parameters (ERP) and their rates as well as Universal Time (UT1-UTC) and Length Of Day (LOD) associated with IGS ephemerides. igr15082.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 | EMR | 9 DAEJ 2 | ESA | JOZE SCH2 SYOG 2 | GFZ | 7 2 | JPL | 9 DAEJ 2 | USN | DGAR SCH2 5. 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 | NGS | 1 2 | USN | 1 19 6. 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. 7. 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. 8. 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 1.1508.2 GPS week: 1508 Day: 2 MJD: 54802.000 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| 71 -18 1 -249 -588 -1054-25.81 925 925 | 97 -328 2483 4375 cod 137| 1 0 0 6 23 -46 -.28 13 12 | -572 516 24 130 emr 45| -4 1 8 -44 -86 -34 .36 16 16 | -1195 831 16 87 esa 95| 0 0 -7 9 -11 11 .21 12 11 | 1155 -1021 19 101 gfz 97| 0 1 -2 -88 -22 19 -.15 15 15 | 343 -704 27 122 iga n/a| 1 1 -1 -10 54 28 -.07 11 11 | 96 -343 61 133 igu n/a| 1 2 1 -157 288 394 -.04 38 34 | 247 -1422 2448 4938 jpl 45| -3 0 8 141 48 10 .51 24 24 | 590 947 24 195 ngs 104| 1 0 1 -43 15 -16 -.42 14 13 | 86 -362 2130 3691 sio 72| 3 -1 0 67 14 99 -.34 22 20 | 0 0 0 0 usn 47| 0 -6 -10 132 89 -33 .06 52 25 | -460 927 73 1821 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 2.1508.2 GPS week: 1508 Day: 2 MJD: 54802.000 Weighted Average PRN | brd cod emr esa gfz iga igu jpl ngs sio usn IGR | ------+-------------------------------------------------------------+ X1 | 1243 5 --- --- --- --- --- --- 549 --- 203 0 | 2 | 510 14 23 15 16 14 24 28 16 25 47 8 | 3 | 984 9 11 7 13 10 27 15 9 23 28 5 | 4 | 773 14 9 6 13 9 24 16 15 21 16 5 | 5 | 756 7 13 10 15 7 25 13 11 17 18 4 | 6 | 880 8 10 7 12 7 67 14 13 22 31 5 | 7E | 589 10 17 14 11 9 53 18 12 19 52 6 | 8E | 724 19 16 15 15 19 67 22 26 40 22 8 | 9E | 702 14 16 11 16 15 77 15 14 40 24 7 | 10 | 842 15 19 10 13 12 40 51 14 16 21 8 | 11 | 789 10 18 13 20 11 28 20 15 23 49 7 | 12 | 493 12 18 15 16 14 38 24 15 19 22 6 | 13 | 1297 12 17 16 15 12 21 22 13 17 34 6 | 14 | 850 12 12 12 17 14 26 20 15 14 47 6 | 15 | 797 14 20 17 23 12 19 26 15 19 21 7 | 16 | 1182 16 22 16 20 14 24 18 16 30 40 8 | 17 | 342 11 11 10 10 8 22 23 9 14 32 5 | 18 | 964 16 20 11 13 14 35 18 16 15 33 6 | 19 | 1094 8 11 9 12 7 36 18 11 10 234 4 | 20E | 697 18 16 12 10 16 43 18 16 20 33 6 | 21 | 680 15 18 13 14 13 28 16 15 20 41 6 | 22 | 460 10 13 11 16 10 26 17 15 15 20 5 | 23 | 413 12 19 12 13 12 20 21 14 14 35 6 | 24 | 1422 11 13 9 13 7 21 11 11 13 25 4 | 25E | 778 15 17 13 15 11 24 17 13 30 28 6 | 26 | 568 11 16 8 16 7 29 10 11 14 18 5 | 27E | 1249 19 15 10 14 12 59 17 16 28 20 6 | 28 | 823 14 20 15 20 12 36 23 17 24 35 7 | 29 | 2351 9 11 9 11 8 56 63 15 16 26 8 | 30 | 846 6 12 9 11 6 29 14 10 16 17 4 | 31E | 507 12 20 12 14 8 33 24 15 18 34 6 | 32 | 831 13 17 11 20 10 29 28 9 28 41 7 | ------+-------------------------------------------------------------+ RMS | 924 13 16 12 15 11 38 24 14 22 52 | WRMS | 924 12 16 11 15 11 34 24 13 20 25 | MEDI | 789 12 16 11 14 11 29 18 15 19 31 | 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 3.1508.2 GPS week: 1508 Day: 2 MJD: 54802.0 CENT| CLK EPO | BRUS | TOW2 | WILL | ----+----------+-------------------+-------------------+-------------------+ cod | cod 3061 | 6 7 18 | 9 12 38 | 12 15 25 | emr | emr 2960 | 7 11 26 | 11 16 36 | 12 23 31 | esa | esa 2976 | 8 11 23 | 10 14 42 | 10 12 16 | gfz | gfz 2949 | 6 11 24 | 10 17 51 | 15 22 42 | igr | igr 2976 | 7 10 23 | 10 14 38 | 9 14 25 | jpl | jpl 2960 | 20 16 35 | 13 29 51 | 14 26 54 | 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 4.1508.2 GPS week: 1508 Day: 2 MJD: 54802.500 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 | -21 1 22 87 3 | 10 20 emr uuuuu | 88 26 73 -61 11 | 54 56 esa uuuuu | -20 -29 228 -289 3 | 16 22 gfz uuuuu | 47 116 -208 180 -18 | 23 28 iga xxxxx | -41 28 -76 91 -12 | 4 18 igu xxxxx | -306 4 -695 93 -38 | 37 74 jpl uuuuu | 24 -150 86 402 10 | -1 15 ngs uuuuu | -84 28 -250 -34 -19 | 17 25 sio uuxxu | -50 -54 127 -263 -16 | 49 51 usn uuuux | -50 -36 127 47 126 | 35 50