Latest IGU summary
This file is the latest summary produced in the IGS UltraRapid orbit generation, which provides a quick look into the most recent IGS analysis of the GPS satellites.
The "REMARKS" section will note if any satellites were not included in the combined solution, due to too few analysis centers providing a solution. Any satellites which have no prediction provided due to a maneuver will also be listed.
Table 2 shows which satellites were eclipsing, the sp3 orbit accuracy code for each PRN, and whether any analysis centers did not provide a solution for any satellites.
This page is designed for humans to read, to check on how the latest UltraRapid analysis went. To obtain UltraRapid products for operational and/or automated use, please see the IGS product table.
Author: AC Coordinator / NOAA NGS
sum-file Version 2.0
Ultra Rapid IGS Orbit Combination - Week 1847 Day: 2 Hour: 12 (Jun 02, 2015)
Contacts: igs.acc@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 Ultra Rapid Orbit files generated and uploaded into CDDIS @ NASA/GSFC are:
igu18472_12.sp3 IGU GPS ephemeris in SP3 format.
igu18472_12.erp Earth Rotation Parameters (ERP) and their rates as well as
Universal Time (UT1-UTC) and Length Of Day (LOD) associated
with IGS ephemerides.
igu18472_12.sum Combination summary report.
REMARKS concerning the IGU Orbit Combination:
---------------------------------------------
1. The following centre clock solutions, which provide broadcast and/or
predicted broadcast clock corrections, were excluded from the combination
but kept in the combination statistics:
-> Broadcast Centre: GOU COU
The reference time scale is based on a linear alignment to the clocks
of a particular centre, which is normally pre-aligned to broadcast GPS
time. The reference centre is chosen from the following list, in order
of availability, and is indicated by 0 TOFT, 0 TDRFT, and non-zero RMS
in Table 1:
-> Reference Centre: EMU USU ESU GFU
Starting on 1-Jul-2009 (GPS Week 1538, day 3, hour 12; MJD 55013.5),
clock predictions are excluded for satellites set unhealthy due to MX
or UNUSUFN NANU events. The centre clock statistics in Table 1 do not
include the excluded satellites; however, these are included in the later
IGU center comparison statistics with the IGS Rapid clocks.
Starting 3-Feb-2012 (GPS Week 1673, day 5, hour 00; MJD 55959.0), a new
solution from Wuhan University (WHU) is included for comparison only. Starting
27-Feb-2012 (GPS Week 1677, day 1, hour 12; MJD 55984.5), a new solution
from NOAA/National Geodetic Survey (NGU) is included for comparison only.
Two changes were made to the IGU starting 8-Aug-2012 (GPS Week 1700, day 3,
hour 12; 56147.5). The WHU and NGU orbits are now included with full weight,
and any AC contribution with orbital frame rotations larger than 300 uas will
be excluded. This threshold is consistent with those used in the IGR rapid
combination.
2. 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:
Centre | PRN list
--------+---------------
GOU | 8
3. The following orbit solutions were excluded from the combination because
less than 3 ACs have submitted results for given satellite(s).
The following table lists the exclusions:
Centre | PRN list
--------+---------------
COU | 8
4. Starting 5-Nov-2006 (GPS Week 1400, day 0, MJD 54044) until 16-Apr-2011
(GPS Week 1631, day 6, MJD 55667) 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. The IGS05 frame is
also the basis for the homogeneously reprocessed IGS products from GPS Weeks
730 to 1459 (1994-2007); see IGSMAIL #6136.
Starting 17-Apr-2011 (GPS Week 1632, day 0, MJD 55668) all IGS products,
are based on the IGS realization of the ITRF2008 reference frame (IGS08).
For more information see IGSMAIL #6354.
Starting 07-Oct-2012 (GPS Week 1709, day 0, MJD 56207) all IGS products,
are based on the updated IGS08 frame (IGb08).
For more information see IGSMAIL #6663.
5. Starting 5-Nov-2006 (GPS Week 1400, day 0, MJD 54044) until 16-Apr-2011
(GPS Week 1631, day 6, MJD 55667) the absolute antenna model is introduced
(IGSMAIL #5438). The antenna phase center offsets and phase center variations
are given in the file:
ftp://igs.org/igscb/station/general/igs05.atx
These antenna calibrations are also used in the homogeneously reprocessed IGS
products from GPS Weeks 730 to 1459 (1994-2007); see IGSMAIL #6136.
Starting 17-Apr-2011 (GPS Week 1632, day 0, MJD 55668) the absolute antenna
model is updated (IGSMAIL #6255 & #6374) as given in the file:
ftp://igs.org/igscb/station/general/igs08.atx
Starting 07-Oct-2012 (GPS Week 1709, day 0, MJD 56207) the igs08.atx absolute
antenna model file gives updated (IGSMAIL #6662) values for the JPSREGANT_DD
and JPSREGANT_SD antennas, plus updates for GPS IIF transmit antennas. This
updated file should be used in conjunction with IGb08. Though, igs08.atx is
also still consistent with IGS08.
ORBIT COMBINATION AND EVALUATION STATISTICS:
--------------------------------------------
Table 1: Transformation of each centre to the combined IGU orbit
and clocks.
WRMS - RMS weighted by the centres SP3 header accuracy codes.
STA - Number of stations in the daily solutions.
Table 1.1847.2 GPS week: 1847 Day: 2 MJD: 57175.500
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]
--------+----------------------------------------------------+------------------------------
cou 131| 0 0 -4 -23 -33 28 .17 23 18 | -174 1113 --- 11250
emu 94| 0 0 2 39 25 -4 .08 13 11 | 0 0 --- 11010
esu 109| 0 0 0 -36 -29 -43 -.18 20 18 | -39920 59030 --- 68550
gfu 98| 0 -3 6 -4 -9 3 .08 26 26 | -925 1231 --- 11200
gou 94| 0 0 -11 -67 39 36 -.61 40 35 | -370 151 --- 13910
siu n/a| 0 0 -2 67 22 -1610 .06 61 59 | 0 0 --- 0
usu 29| -1 -1 9 185 447 -232 -.11 48 46 | -816 557 --- 9037
whu 111| 0 -1 7 91 265 192 -.59 65 52 | 3499 -5724 --- 11400
Table 2: Fit for each satellite and each centre resulting from weighted
average combination.
The last column gives the IGU 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 2.1847.2 GPS week: 1847 Day: 2 MJD: 57175.500
Weighted Average
PRN | cou emu esu gfu gou siu usu whu IGU |
------+----------------------------------------------+
1 | 24 10 13 15 29 114 29 35 8 |
2 | 14 12 18 16 68 45 35 34 11 |
3 | 9 4 14 25 30 41 34 29 7 |
4 | 12 6 11 15 30 52 31 46 6 |
5 | 17 8 29 14 32 53 42 27 9 |
6 | 12 7 17 18 27 32 35 45 7 |
7 | 12 9 17 25 27 29 32 37 8 |
X8 | ---- --- --- --- --- --- --- --- 0 |
9E | 13 9 21 15 22 114 91 54 7 |
10 | 15 18 16 25 32 33 52 26 10 |
11 | 17 11 19 15 26 48 30 45 8 |
12 | 17 4 21 22 31 57 28 51 8 |
13E | 13 19 9 34 33 26 29 28 10 |
14E | 15 27 20 30 20 83 58 43 12 |
15 | 78 12 34 56 29 51 66 261 23 |
16 | 14 9 16 25 86 104 36 32 14 |
17 | 20 17 46 35 47 30 68 131 15 |
18 | 19 17 17 34 38 48 46 24 11 |
19 | 9 9 21 28 41 24 46 35 9 |
20 | 21 14 18 25 25 59 31 26 9 |
21 | 32 10 18 11 67 28 72 36 13 |
22 | 17 17 16 27 22 22 44 27 9 |
23E | 20 18 19 21 37 32 30 45 10 |
X24 | 24 15 21 29 --- 80 42 30 12 |
25 | 10 9 14 19 38 29 67 35 8 |
26 | 18 6 27 17 70 107 49 39 12 |
27E | 25 27 16 35 33 24 --- 50 13 |
28 | 10 5 12 23 37 71 39 31 8 |
29 | 11 10 18 26 47 44 29 69 10 |
30 | 7 6 16 21 30 56 38 36 7 |
31 | 40 6 19 31 33 113 83 33 12 |
32 | 24 11 13 24 37 19 35 31 10 |
------+----------------------------------------------+
RMS | 23 13 20 26 40 61 48 65 |
WRMS | 18 11 18 26 35 59 46 52 |
MEDI | 17 10 18 25 32 48 38 35 |
Table 3: Earth Orientation Parameters daily summary.
Centre ERP, ERP Rates and LOD differences with respect to
IGU 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: 7-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.
Remark: Until 1766_2_06, COU submit ERP-products for 00 and 12 UT
only, for 06 and 18 UT extrapolations made by the
combination processes were used. Starting 1766_2_12, COU
provides ERP-products for all combinations.
Table 3.1847.2 GPS week: 1847 Day: 2 MJD: 57175.000
AC LOD AC LOD
CENT FLAG | Xpole Ypole Xrt Yrt LOD | BIAS BIAS RMS
| [uas] [uas] [uas/d] [uas/d] [us]| [us] [us]
------------+----------------------------------------+------------------
cou uuuuu | 15 22 22 19 1 | -1 11
emu uuuuu | -25 -37 -32 -30 7 | -5 10
esu uuuuu | -8 18 63 15 1 | -1 11
gfu uuuuu | 20 -7 -70 -7 -12 | -6 10
gou uuuuu | 58 82 68 62 3 | -1 11
ngu xxxxx | 39 70 -144 -19 -9 | 18 36
usu xxxxx | -314 -183 -216 -11 -2 | -14 21
whu xxxxx | -20 -142 334 53 17 | -24 33
Table 3.1847.3 GPS week: 1847 Day: 3 MJD: 57176.000
AC LOD AC LOD
CENT FLAG | Xpole Ypole Xrt Yrt LOD | BIAS BIAS RMS
| [uas] [uas] [uas/d] [uas/d] [us]| [us] [us]
------------+----------------------------------------+------------------
cou uuuuu | 63 47 47 25 3 | -1 11
emu uuuuu | -31 -60 -7 -24 5 | -5 10
esu uuuuu | 81 39 88 21 6 | -1 11
gfu uuuuu | -24 -8 -45 -1 -11 | -6 10
gou uuuuu | -178 74 -237 -8 -3 | -1 11
ngu xxxxx | -306 61 -442 175 -66 | 18 36
usu xxxxx | -587 -164 -231 15 -108 | -14 21
whu xxxxx | -608 19 370 95 0 | -24 33
Comments