Author: AC Coordinator / NOAA NGS sum-file Version 2.0 Rapid IGS Orbit Combination - Week 1511 Day: 4 (Dec 25, 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: igr15114.sp3 IGR GPS ephemeris in SP3 format. igr15114.clk IGR GPS satellite and station clocks in RINEX format. igr15114.cls IGR GPS clock combination summary report. igr15114.erp Earth Rotation Parameters (ERP) and their rates as well as Universal Time (UT1-UTC) and Length Of Day (LOD) associated with IGS ephemerides. igr15114.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 | COD | TIDB 4 | EMR | 21 32 MCM4 4 | ESA | SYOG TIDB TSKB 4 | GFZ | 7 32 4 | JPL | 10 32 SANT 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 ----+--------+--------------- 4 | USN | 1 21 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 1.1511.4 GPS week: 1511 Day: 4 MJD: 54825.000 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| -32 43 -9 2590 208 -3074-27.14 902 902 | -922 1382 2753 4692 cod 139| 0 1 0 -49 72 -6 -.21 11 11 | -1290 1481 27 111 emr 44| 0 -1 2 -54 -63 -51 .34 19 19 | 1925 -1398 18 95 esa 95| -1 -1 -6 60 14 13 .33 11 10 | -1824 2840 21 90 gfz 87| 0 -2 -6 14 -43 -33 -.18 14 14 | -722 1385 26 145 iga n/a| 0 0 0 -9 -9 102 -.02 8 8 | -955 1426 30 111 igu n/a| 0 0 4 -127 254 471 -.05 43 39 | -839 -266 2340 5226 jpl 45| -1 0 10 3 -47 -34 .45 24 23 | 2575 -1722 20 124 ngs 97| 0 1 0 3 4 8 -.39 13 12 | -915 1373 2431 4224 sio 62| 5 1 3 21 -16 67 -.30 20 19 | 0 0 0 0 usn 46| 0 -2 0 46 51 25 .12 45 34 | 1604 -1819 92 1843 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 2.1511.4 GPS week: 1511 Day: 4 MJD: 54825.000 Weighted Average PRN | brd cod emr esa gfz iga igu jpl ngs sio usn IGR | ------+-------------------------------------------------------------+ X1 | 658 6 --- --- --- --- --- --- --- --- 588 0 | 2 | 483 16 26 16 16 10 34 20 14 14 42 7 | 3 | 1496 8 15 8 10 8 34 12 11 15 35 4 | 4 | 1131 9 10 8 14 7 27 13 13 12 33 4 | 5 | 789 15 13 8 10 9 33 15 11 22 36 5 | 6 | 821 9 15 6 10 9 18 10 9 16 35 4 | 7 | 783 8 22 9 21 6 24 24 12 31 50 7 | 8 | 675 11 16 11 14 6 31 16 13 28 35 6 | 9 | 604 9 16 12 11 7 60 13 11 17 28 5 | 10E | 1409 17 17 13 12 14 51 18 19 45 31 8 | 11 | 1132 19 20 11 13 7 60 40 16 10 51 8 | 12 | 978 11 21 15 11 10 36 26 11 17 35 6 | 13 | 908 10 21 8 14 7 28 20 13 22 72 7 | 14 | 1327 10 22 10 13 6 48 25 12 19 49 6 | 15 | 322 9 21 11 13 9 35 19 12 15 31 5 | 16 | 837 9 26 11 15 8 22 25 14 16 31 6 | 17 | 254 8 14 11 13 9 28 30 11 14 40 6 | 18E | 941 9 20 14 15 9 34 23 14 14 33 6 | 19 | 658 12 17 8 10 8 22 54 16 15 51 8 | 20E | 1124 6 14 13 21 7 57 25 12 20 52 6 | 21 | 757 10 23 8 13 7 29 24 10 21 130 6 | 22E | 774 8 18 11 17 7 81 23 16 9 37 6 | 23 | 449 10 31 13 18 9 34 18 14 13 42 7 | 24 | 743 6 15 6 9 7 56 10 13 10 32 4 | 25 | 909 12 14 8 14 6 34 22 11 32 30 6 | 26 | 987 7 16 13 9 8 37 12 11 12 24 4 | 27 | 1204 10 14 10 14 6 21 18 13 28 32 6 | 28 | 1061 9 23 13 10 6 26 23 14 20 32 6 | 29 | 671 14 15 7 17 10 25 35 12 12 27 6 | 30 | 759 11 17 7 13 7 37 16 10 20 30 5 | 31 | 532 9 19 8 12 8 35 22 9 15 28 5 | 32E | 941 21 26 15 16 13 106 28 16 21 45 8 | ------+-------------------------------------------------------------+ RMS | 902 11 19 11 14 8 43 24 13 20 45 | WRMS | 902 11 19 10 14 8 39 23 12 19 34 | MEDI | 789 9 17 11 13 8 34 22 12 16 35 | 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 3.1511.4 GPS week: 1511 Day: 4 MJD: 54825.0 CENT| CLK EPO | BRUS | WILL | ----+----------+-------------------+-------------------+ cod | cod 3069 | 7 11 23 | 13 11 22 | emr | emr 2968 | 13 14 37 | 13 14 26 | esa | esa 2976 | 7 10 23 | 11 10 23 | gfz | gfz 2956 | 10 11 23 | 15 14 29 | igr | igr 2973 | 13 13 32 | 12 14 26 | jpl | jpl 2967 | 11 12 55 | 13 15 29 | 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 4.1511.4 GPS week: 1511 Day: 4 MJD: 54825.500 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 | -96 36 85 -160 9 | -7 21 emr uuuuu | 54 37 -204 3 8 | 33 40 esa uuuuu | -38 -37 56 104 10 | -7 25 gfz uuuuu | 32 -27 94 -177 -12 | -2 22 iga xxxxx | -5 13 -1 -1 4 | 0 19 igu xxxxx | -356 84 -657 -145 -16 | -28 65 jpl uuuuu | 76 10 71 172 4 | -11 21 ngs uuuuu | -74 6 -101 -99 -5 | -17 26 sio uuxxu | 16 18 20 -105 14 | 28 38 usn uuuuu | -5 94 280 120 -13 | 16 40