Author: AC Coordinator / NOAA NGS sum-file Version 2.0 Rapid IGS Orbit Combination - Week 1510 Day: 6 (Dec 20, 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: igr15106.sp3 IGR GPS ephemeris in SP3 format. igr15106.clk IGR GPS satellite and station clocks in RINEX format. igr15106.cls IGR GPS clock combination summary report. igr15106.erp Earth Rotation Parameters (ERP) and their rates as well as Universal Time (UT1-UTC) and Length Of Day (LOD) associated with IGS ephemerides. igr15106.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 ----+--------+--------------- 6 | ESA | SYOG 6 | GFZ | 7 32 6 | USN | 28 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 ----+--------+--------------- 6 | USN | 1 28 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 1.1510.6 GPS week: 1510 Day: 6 MJD: 54820.000 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| 2 3 24 1227 39 -3158-27.33 984 984 | -377 340 2333 4000 cod 126| 1 2 0 -58 14 -36 -.06 10 10 | -1245 1295 22 93 esa 95| 0 1 0 22 12 3 .38 8 8 | -659 671 13 62 gfz 96| -1 -1 -5 -11 -9 10 -.06 12 12 | -197 360 21 101 iga n/a| 0 1 0 -15 0 271 .11 7 6 | -647 1130 67 96 igu n/a| 0 0 -1 -2 -63 -50 .14 60 60 | -299 -629 2446 4511 ngs 101| 0 3 0 -66 -112 17 -.45 14 13 | -600 1015 2183 3523 sio 69| 1 -2 3 85 68 42 -.12 19 16 | 0 0 0 0 usn 44| -1 -8 1 273 150 -50 .24 54 36 | 1730 666 98 1917 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 2.1510.6 GPS week: 1510 Day: 6 MJD: 54820.000 Weighted Average PRN | brd cod esa gfz iga igu ngs sio usn IGR | ------+---------------------------------------------------+ X1 | 501 4 --- --- --- --- --- --- 238 0 | 2 | 570 11 9 15 7 23 12 22 51 7 | 3 | 1105 9 7 8 6 28 11 24 42 6 | 4 | 855 10 10 10 8 29 11 25 54 7 | 5 | 915 11 5 10 9 286 13 15 24 5 | 6 | 1128 11 6 10 7 31 10 22 32 5 | 7 | 493 10 6 15 4 49 14 12 52 6 | 8 | 1546 10 7 11 6 16 15 13 31 5 | 9 | 959 10 3 10 6 24 15 12 28 5 | 10E | 1745 17 13 16 12 43 13 43 48 10 | 11 | 938 7 7 14 7 67 15 17 65 7 | 12 | 843 7 7 8 5 22 9 15 44 5 | 13 | 1110 18 10 15 7 36 14 10 51 7 | X14 | 920 7 7 12 45 --- 21 --- 53 7 | 15 | 459 7 9 8 5 21 19 11 41 6 | 16 | 763 9 8 8 6 28 11 15 44 5 | 17 | 350 8 7 17 7 15 11 21 43 6 | 18E | 916 9 8 12 11 25 15 18 57 7 | 19 | 805 9 6 9 5 35 12 13 70 6 | 20E | 1178 10 8 12 6 37 18 25 50 7 | 21 | 773 10 8 11 8 22 11 20 49 6 | 22E | 626 6 9 12 5 14 15 10 39 5 | 23 | 492 10 9 13 7 47 12 11 49 6 | 24 | 952 6 6 8 5 24 11 14 32 4 | 25 | 1495 12 6 11 7 53 14 15 23 5 | 26 | 669 9 10 11 7 18 14 14 24 5 | 27 | 1257 9 8 10 5 9 16 13 28 5 | 28 | 966 8 7 14 6 12 15 14 183 5 | 29 | 1330 11 6 10 4 13 12 8 43 5 | 30 | 1018 12 6 7 5 14 8 20 25 5 | 31 | 821 6 6 9 6 39 10 18 40 5 | 32E | 805 12 11 17 9 12 21 33 29 8 | ------+---------------------------------------------------+ RMS | 984 10 8 12 7 60 14 19 54 | WRMS | 984 10 8 12 6 60 13 16 36 | MEDI | 915 9 7 11 6 24 13 15 43 | 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 3.1510.6 GPS week: 1510 Day: 6 MJD: 54820.0 CENT| CLK EPO | BRUS | TOW2 | WILL | ----+----------+-------------------+-------------------+-------------------+ cod | cod 3072 | 6 6 19 | 19 18 51 | 12 9 18 | esa | esa 2976 | 8 9 23 | 17 15 48 | 11 8 18 | gfz | gfz 2957 | 8 9 24 | 19 18 59 | 16 13 24 | igr | igr 2974 | 7 9 21 | 18 16 53 | 12 9 19 | 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 4.1510.6 GPS week: 1510 Day: 6 MJD: 54820.500 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 | -25 72 -175 200 8 | -9 20 esa uuuuu | -47 -7 -139 -131 -3 | 3 21 gfz uuuuu | 3 30 -54 125 -2 | 7 20 iga xxxxx | -8 22 -126 115 15 | -2 17 igu xxxxx | 79 24 112 302 -6 | -38 73 ngs uuuuu | 161 44 291 9 1 | -13 24 sio uuxxu | -106 -74 101 58 13 | 30 37 usn uuuuu | -29 -50 -22 338 1 | 18 37