[IGSMAIL-1163] Wk 0821-4 IGS Final Orbits
AC
AC
Tue Dec 19 10:10:24 PST 1995
******************************************************************************
IGS Electronic Mail Tue Dec 19 10:10:24 PST 1995 Message Number 1163
******************************************************************************
Author: AC Coordinator
Subject: Wk 0821-4 IGS Final Orbits
*******************************************************************************
IGS Final orbits/clocks completed and put onto CDDIS (Weeks 821 - 824)
(Oct 01 - Oct 28, 1995)
*******************************************************************************
The IGS Rapid Orbits for this period were recomputed using up to date
orbits and the final EOP values of Bulletin B, published by IERS. ( Daily
values, page 2 of Bull. B ) The EOP were corrected for the difference
between the IERS pole series and ITRF as published in the IERS 1993 Annual
Report (p. II-19, Table II-3), so both the IGS orbits and the associated
ERP files are consistent with ITRF93 (current epoch).
We have downloaded all the submitted ephemeris and ERP files from CDDIS
before the final orbit/clock combination to ensure that the sets are
complete and up to date. In the final combination we have largely followed
the actions taken during the Rapid orbit generation and since there were
very few orbit resubmissions, both the IGS Rapid and Final orbits are
virtually the same except for the orientation difference (IGS mean pole and
Bull.B). Orbit evaluation are also nearly the same, since we used centre
specific ERP in the long arc evaluations. For more information see the
corresponding summary files on CDDIS.
The clock solution alignment and centre clock weight assignment are based
on non-SA broadcast satellite corrections only (PRN12, 15, 28). This should
result in an objective clock weighting, provided that the non-SA satellites
are representative of centre clock solution quality. Starting with the GPS
week 756 the new IGS erp format (see IGSMAIL# 662) is used by all Analysis
Centres and for the IGS erp files. ERP rates, whenever given, are also
utilized in both orbit combination and the long arc evaluation.
PRODUCTS GENERATED:
The resulting final IGS ephemeris and clocks are in daily files in the SP3
format. The sat. orb. accuracy codes displayed in the headers are based on
weighted RMS for each satellite. Note that each file contains all the submitted
satellites. If a satellite or centre had to be excluded from the combination it
is noted in the summary file along with the reason for doing so.
The IGS FINAL ORBIT files generated and uploaded into CDDIS @ NASA/GSFC are:
IGS08210-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0821
IGS08220-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0822
IGS08230-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0823
IGS08240-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0824
IGS08217.ERP EOP associated with the above orbits (Bull. B aligned to ITRF)
IGS08227.ERP EOP associated with the above orbits (Bull. B aligned to ITRF)
IGS08237.ERP EOP associated with the above orbits (Bull. B aligned to ITRF)
IGS08247.ERP EOP associated with the above orbits (Bull. B aligned to ITRF)
IGS08217.SUM Complete summary/statistics report
IGS08227.SUM Complete summary/statistics report
IGS08237.SUM Complete summary/statistics report
IGS08247.SUM Complete summary/statistics report
The old Rapid Orbit files have been renamed (on CDDIS) to:
(Note this is temporary, based on discussions with ACs and GB and may be
changed)
IGR08210-6.SP3 Rapid service orbits/clocks for days 0-6, week 0821
IGR08220-6.SP3 Rapid service orbits/clocks for days 0-6, week 0822
IGR08230-6.SP3 Rapid service orbits/clocks for days 0-6, week 0823
IGR08240-6.SP3 Rapid service orbits/clocks for days 0-6, week 0824
IGR08217.ERP IGS Mean EOP associated with the above orbits
IGR08227.ERP IGS Mean EOP associated with the above orbits
IGR08237.ERP IGS Mean EOP associated with the above orbits
IGR08247.ERP IGS Mean EOP associated with the above orbits
IGR08217.SUM Rapid service complete summary/statistic report
IGR08227.SUM Rapid service complete summary/statistic report
IGR08237.SUM Rapid service complete summary/statistic report
IGR08247.SUM Rapid service complete summary/statistic report
*****************************************************************************
REMARKS/CORRECTIONS:
The Wk 821-824 IGS Final Orbit combination was redone on Dec. 18, 1995 with
the new issue of Bull. 94. This IGS Final Orbit summary is based on the
revised Bull B 94, reissued by IIERS on Dec 8, 1995.
************* NOTE: ***************************
Since Wk 803 the IGS Rapid combinations are performed directly in ITRF frame,
without any EOP alignments. The associated erp files (IGR0WWW7.erp) contain
weighted averages of all submitted erp solutions given at 12h UT each day
(using the orbit weights), augmented with the current IERS Bull.A UT1-UTC.
Consequently, since Wk 803, the IGR erp contains 7 daily EOP values at 12h UT,
unlike the Final orbit erp (and the Rapid orbit erp prior Wk 803) which
contain 9 daily IERS EOP values at 0h UT to facilitate accurate interpolation
for the whole week period.
***********************************************
The following table shows the average statistics of the Final Orbit/clock
combination for the current period (Wks 0821-0824).
Start: 95 Oct 01 / wk821
End: 95 Oct 28 / wk824
STA DX DY DZ RX RY RZ SCL RMS WRMS LaRMS RMSc Days
----------------------------------------------------------------------------
cod 61 0.00 0.03 0.00 -0.38 -0.26 -0.06 0.0 7 7 8 1.4 28
0.01 0.01 0.01 0.11 0.12 0.18 0.1
emr 28 0.01 -0.01 -0.01 0.07 0.03 0.03 -0.1 9 8 13 0.8 28
0.01 0.01 0.01 0.25 0.23 0.13 0.1
esa 47 0.01 -0.02 -0.03 0.50 0.18 0.11 0.0 17 13 15 28.2 28
0.01 0.01 0.01 0.21 0.22 0.21 0.1
gfz 47 -0.03 -0.02 0.00 -0.21 0.00 -0.17 -0.2 10 9 13 6.8 28
0.01 0.01 0.00 0.13 0.14 0.13 0.1
jpl 34 0.02 0.04 0.00 -0.43 0.01 0.12 0.1 9 9 10 0.7 28
0.01 0.01 0.01 0.23 0.20 0.15 0.1
ngs 43 0.01 -0.02 0.01 -0.24 0.22 0.02 -0.1 11 11 15 30186.1 28
0.01 0.01 0.01 0.32 0.28 0.27 0.1
sio 103 -0.01 -0.03 0.02 -0.24 -0.04 -0.13 0.2 10 10 16 0.0 28
0.02 0.02 0.02 0.43 0.49 0.59 0.1
Units: m - DX, DY, DZ
mas - RX,RY,RZ
ppb - SCL
cm - RMS, WRMS, LaRMS (Long arc orbit RMS)
ns - RMSc (sv clock)
The following table shows the average statistics of the Final Orbit/clock
combination for the current year (Wks 0782-0824).
Start: 95 Jan 01 / wk782
End: 95 Oct 28 / wk824
STA DX DY DZ RX RY RZ SCL RMS WRMS LaRMS RMSc Days
----------------------------------------------------------------------------
cod 56 0.00 0.02 0.00 -0.43 -0.06 0.04 0.0 10 9 11 4096.2 301
0.01 0.02 0.01 0.23 0.30 0.20 0.1
emr 26 0.01 -0.02 0.00 -0.10 -0.07 0.13 -0.1 10 10 15 0.9 301
0.01 0.01 0.01 0.36 0.31 0.19 0.2
esa 39 0.00 -0.01 -0.03 0.33 0.14 -0.04 0.1 430 15 18 27.5 301
0.01 0.01 0.01 0.43 0.40 0.35 0.2
gfz 44 -0.03 -0.01 0.00 -0.23 0.13 -0.22 -0.3 42 42 15 29.8 301
0.01 0.01 0.01 0.19 0.25 0.18 0.1
jpl 33 0.01 0.04 0.00 -0.49 0.05 0.12 0.1 10 10 10 0.9 301
0.01 0.01 0.01 0.25 0.28 0.15 0.1
ngs 38 0.01 -0.02 -0.01 -0.34 0.25 -0.05 0.4 19 18 20 11615.9 301
0.02 0.02 0.02 0.38 0.41 0.36 0.4
sio 49 0.01 -0.06 0.03 0.12 -0.18 -0.30 0.1 4325 2904 21 0.0 301
0.02 0.03 0.07 0.63 0.70 1.95 0.2
Units: m - DX, DY, DZ
mas - RX,RY,RZ
ppb - SCL
cm - RMS, WRMS, LaRMS (Long arc orbit RMS)
ns - RMSc (sv clock)
[Mailed From: Jan Kouba <kouba at geod.emr.ca>]
More information about the IGSMail
mailing list