[IGSMAIL-5590]: IGS Rapid Combination (IGR): 1423 1 (NEW_CLOCKS)
Gerd Gendt3
igsacc at gfz-potsdam.de
Tue Apr 24 23:45:20 PDT 2007
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IGS Electronic Mail 24 Apr 23:45:34 PDT 2007 Message Number 5590
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Author: AC Coordinator / GFZ Potsdam
sum-file Version 2.0
Rapid IGS Orbit Combination - Week 1423 Day: 1 (Apr 16, 2007)
Contacts: G. Gendt (gendt at gfz-potsdam.de),
Th. Nischan ( nisn at gfz-potsdam.de)
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:
igr14231.sp3 IGR GPS ephemeris in SP3 format.
igr14231.clk IGR GPS satellite and station clocks in RINEX format.
igr14231.cls IGR GPS clock combination summary report.
igr14231.erp Earth Rotation Parameters (ERP) and their rates as well as
Universal Time (UT1-UTC) and Length Of Day (LOD) associated
with IGS ephemerides.
igr14231.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 JPL and USN.
Day | Centre | PRN/STA list
----+--------+---------------
1 | EMR | 26
1 | ESA | TIDB
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
----+--------+---------------
1 | NGS | 32
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 1.1423.1 GPS week: 1423 Day: 1 MJD: 54206.000
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| 28 -50 10 -575 915 -3250-26.14 1197 1197 | -689 1029 2623 4057
cod 116| 0 -2 1 21 54 -53 -.29 17 17 | -1332 1592 38 72
emr 38| 0 0 0 -111 -87 2 .37 24 24 | 5912 477 56 102
esa 40| 0 4 -3 75 -47 126 .12 23 23 | 6044 410 43 97
gfz 91| 2 0 2 -76 -2 6 -.01 15 15 | 5178 -12390 0 105
iga n/a| 0 0 -2 -1 -37 -109 -.09 11 11 | -688 1011 61 112
igu n/a| 0 0 -4 -149 -307 114 -.14 39 33 | -704 1023 3155 5155
ngs 93| -1 -1 0 15 -11 -44 .01 17 15 | -697 1037 2476 3769
sio 68| 3 -3 -7 23 60 72 -.03 40 39 | 0 0 0 0
usn 45| -2 1 -4 123 44 27 .05 29 26 | 3392 915 92 2011
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 2.1423.1 GPS week: 1423 Day: 1 MJD: 54206.000
Weighted Average
PRN | brd cod emr esa gfz iga igu ngs sio usn IGR |
------+--------------------------------------------------------+
1E | 1255 16 28 31 20 13 79 15 38 27 9 |
2 | 812 14 23 16 12 12 51 16 35 36 8 |
3 | 1172 17 16 18 15 12 44 20 37 22 7 |
4 | 1886 17 22 19 12 10 19 19 23 20 7 |
5 | 925 20 21 17 11 9 29 13 39 22 7 |
6 | 1418 20 23 22 14 10 24 14 21 14 7 |
7 | 727 19 21 25 17 10 38 12 32 25 8 |
8 | 1011 11 22 14 14 7 19 12 49 29 8 |
9 | 784 9 15 23 11 9 20 16 32 28 7 |
10 | 940 25 16 19 13 20 39 16 28 29 8 |
11 | 892 19 30 26 17 13 20 20 32 36 9 |
12 | 880 17 19 21 14 9 22 14 45 30 8 |
13E | 972 16 22 18 18 8 69 15 23 37 8 |
14E | 1237 15 22 22 13 11 71 15 32 34 8 |
16 | 878 16 30 19 12 12 20 20 43 25 8 |
17 | 608 13 27 16 15 8 26 16 26 36 8 |
18 | 872 16 22 24 15 7 27 20 38 23 8 |
19 | 824 15 22 29 14 16 36 22 29 33 9 |
20 | 717 18 22 26 16 8 30 20 53 33 10 |
21 | 862 25 25 33 17 14 24 15 52 22 10 |
22 | 1373 18 24 43 18 10 48 19 37 26 10 |
23E | 839 14 23 23 16 10 31 19 48 24 9 |
24 | 914 15 22 19 12 11 25 13 43 18 7 |
25 | 655 11 20 24 11 10 18 15 35 35 8 |
26E | 3900 15 43 25 25 16 72 21 37 30 11 |
27 | 585 21 22 16 15 7 28 15 47 27 8 |
28 | 797 17 28 23 21 12 25 14 60 51 11 |
X29E | 580 15 39 --- 16 18 91 14 65 24 11 |
30 | 612 18 19 18 11 6 26 12 53 25 8 |
31 | 394 19 27 26 21 15 33 21 52 31 10 |
X32 | ---- 6 --- --- --- --- --- 468 --- --- 0 |
------+--------------------------------------------------------+
RMS | 1197 17 24 23 15 11 39 17 40 29 |
WRMS | 1197 17 24 23 15 11 33 15 39 26 |
MEDI | 872 16 22 22 15 10 28 16 37 27 |
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 3.1423.1 GPS week: 1423 Day: 1 MJD: 54206.0
CENT| CLK EPO | BRUS | TOW2 | WILL |
----+----------+-------------------+-------------------+-------------------+
cod | cod 2959 | 7 16 27 | 15 22 45 | 15 9 25 |
emr | emr 2868 | 17 30 33 | 15 18 54 | 23 10 30 |
esa | esa 2784 | 45 20 64 | 18 29 58 | 17 13 29 |
gfz | gfz 2852 | 11 22 27 | 16 17 49 | 22 11 24 |
igr | igr 2875 | 24 10 47 | 17 23 35 | 16 13 21 |
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 4.1423.1 GPS week: 1423 Day: 1 MJD: 54206.500
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 | -104 -21 22 -196 1 | -6 18
emr uuuuu | 112 96 95 294 4 | 81 83
esa uuuuu | 46 -175 -234 -111 2 | 57 62
gfz uuuuu | 8 77 11 -23 0 | 20 31
iga xxxxx | 3 -6 -13 -157 -19 | -9 18
igu xxxxx | 287 151 86 92 -61 | -7 48
ngs uuuuu | 17 17 71 -34 -24 | -24 68
sio uuuuu | -80 -125 12 237 23 | 3 103
usn uuuuu | -3 2 -39 192 0 | 51 56
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