[IGSREPORT-18452] Wk 1576 IGS SINEX Combination
igs-rf at ign.fr
igs-rf at ign.fr
Wed Apr 7 07:02:25 PDT 2010
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IGS Electronic Report 07 Apr 07:02:53 PDT 2010 Message Number 18452
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Authors: B. Garayt, P. Rebischung
===============================================================
Combined AC solution for GPS week 1576 - 10/03/21 to 10/03/27
===============================================================
1) Contacts:
============
e-mail: igs-rf at ign.fr
Tel: 0033143988197 (Bruno Garayt)
Fax: 0033143988450
2) Products:
============
All products are available at:
CDDIS: ftp://cddis.gsfc.nasa.gov/gps/products
SOPAC: ftp://garner.ucsd.edu/pub/products
IGN: ftp://igs.ensg.eu/pub/igs/products
ftp://igs.ign.fr/pub/igs/products
igs10P1576.snx Combined weekly solution
igs10P1576.erp Daily Earth Rotation Parameters
igs10P1576.sum This file
igs10P1576.itr Residuals between AC solutions and IGS05 for the RF stations
igs10P1576.res Residuals between AC solutions and combined weekly solution
IGS10P12.snx Cumulative combined solution
IGS10P12.res Residuals between AC solutions and cumulative solution
igs00p03.erp Daily Earth Rotation Parameters since GPS week 860
3) Combination Strategy:
========================
The AC solutions are processed using the following procedure:
3-1) The AC solutions are checked/corrected for possible format problems,
station names inconsistencies, etc...
3-2) Constrained AC solutions are unconstrained according to the information
given in their SOLUTION/APRIORI blocks and then minimally constrained.
AC solutions given in the form of a normal matrix (esa) are inverted by
adding minimal constraints.
3-4) The weekly AC solutions are combined. The 7-parameters singularity is
avoided by using internal constraints. Iterations are performed until no
residuals exceed 5 cm or 5 sigma.
3-5) The combined solution is compared to IGS05 propagated at current week
(datum). Some outliers may be removed from the datum. Finally, the
combined solution is aligned to the datum using a 7-parameters
transformation.
3-6) The AC solutions NOT used in the combination are compared to the combined
solution in order to identify and remove outliers.
3-7) The weekly combined solution is added to the cumulative solution.
Iterations are performed until no residuals exceed 3 cm or 3 sigma in the
weekly solution.
3-8) The updated cumulative solution is compared to IGS05 (datum). Some outliers
may be removed from the datum. Finally, the cumulative solution is aligned
to the datum using a 14-parameters transformation.
4) Remarks:
===========
mit = mit15767.snx
mig = mit1576g.snx
ITR = IGS05.snx
igs = igs10P1576.snx
IGS = IGS10P12.snx
grg, mig, ncl are not used in the combination.
They are only used for comparison.
Solutions with manual station deletion:
4-1) Starting with GPS week 1400, the solutions are aligned to the
IGS05.snx realization of ITRF2005.
4-2) Starting with GPS week 1078, UT1-UTC from IERS Bulletin A
is included in the erp files.
4-3) Starting with GPS week 1412, the accumulated ERP file has been
changed from "igs00p02.erp" to "igs00p03.erp". The main changes
are:
1) Correction of the pole position from IGb00 to IGS05 using the
transformation in:
http://igscb.jpl.nasa.gov/mail/igsmail/2006/msg00178.html
2) Marginal ERP's in GPS week 1161 were replaced by reprocessed
values.
5) Results:
============
5-1) AC (Variance Factor)^0.5 estimates:
=============================================
At each iteration, the variance factor for solution s is estimated by :
VF = (vs'*Ps*vs)/fs with fs = nobss - tr(As*Q*As'*Ps)
vs : residuals of solution s
Ps : weight matrix of solution s
nobss : number of observations of solution s
As : design matrix of solution s
Q : total covariance matrix
This variance factor is used to rescale the covariance matrix of solution s
for the next iteration.
Another scale factor is computed for each solution s, by comparing it to
the official cumulative solution of previous week (IGS) :
SF = (vs'*Ps*vs)/(3*nstas) with vs : residuals of the comparison
Ps : weight matrix of solution s
nstas : number of common stations
Solution |# sta| #RF | Final VF | SF |
---------------|-----|-----|---------------|---------------|
cod | 248 | 64 | 6.696 | 25.579 |
emr | 85 | 46 | 2.438 | 6.614 |
esa | 134 | 44 | 3.090 | 6.201 |
gfz | 199 | 64 | 4.457 | 19.955 |
jpl | 110 | 40 | 5.135 | 11.901 |
mit | 257 | 68 | 0.646 | 2.682 |
ngs | 215 | 66 | 16.151 | 40.352 |
sio | 268 | 67 | 0.743 | 2.779 |
grg | 108 | 40 | ------ | 11.899 |
mig | 426 | 69 | ------ | 2.486 |
igs | 380 | 69 | ------ | ------ |
---------------|-----|-----|---------------|---------------|
5-2) Solution Residuals weighted Average & STD:
====================================================
5-2-1) With respect to the IGS05 stations:
=============================================
Solution | Weighted Average (mm) | STD (mm) |
| N E U | N E U |
---------------|---------------------------|---------------------------|
cod 64 | -0.6 0.2 0.3 | 3.1 3.0 8.0 |
emr 46 | -0.2 0.4 0.1 | 3.3 2.9 8.2 |
esa 44 | -0.8 0.2 0.3 | 3.9 3.3 8.5 |
gfz 64 | -0.1 0.2 0.2 | 2.8 3.0 8.7 |
jpl 40 | -0.9 -0.0 0.1 | 2.9 3.5 8.1 |
mit 68 | 0.2 0.3 0.3 | 2.8 3.1 8.8 |
ngs 66 | -0.1 0.2 0.0 | 2.9 3.3 7.9 |
sio 67 | 0.2 0.4 0.7 | 3.4 3.1 8.6 |
grg 40 | -0.4 0.1 0.3 | 4.0 3.3 6.5 |
mig 69 | -0.5 0.3 0.3 | 2.9 2.9 8.3 |
---------------|---------------------------|---------------------------|
5-2-2) With respect to the Weekly Combination:
=================================================
Solution | Weighted Average (mm) | STD (mm) |
| N E U | N E U |
---------------|---------------------------|---------------------------|
cod 233 | -0.4 -0.0 0.1 | 0.8 0.6 2.6 |
emr 85 | -0.1 0.1 -0.2 | 2.1 1.0 4.7 |
esa 132 | -0.0 0.0 0.2 | 2.6 1.4 4.6 |
gfz 199 | -0.0 -0.0 -0.0 | 0.5 0.6 2.1 |
jpl 109 | -0.5 0.0 -0.1 | 1.7 2.3 5.0 |
mit 231 | 0.3 0.0 -0.1 | 0.6 0.6 1.8 |
ngs 205 | 0.1 0.0 0.2 | 1.7 2.0 4.4 |
sio 264 | 0.2 0.1 0.2 | 1.5 0.8 2.5 |
grg 106 | -0.7 -0.2 0.0 | 3.4 2.9 5.1 |
mig 378 | -0.3 0.0 -0.1 | 0.4 0.5 0.9 |
ITR 69 | 0.1 -0.3 -0.2 | 2.8 3.0 8.2 |
---------------|---------------------------|---------------------------|
5-2-3) With respect to the Cumulative Combination:
=====================================================
Solution | Weighted Average (mm) | STD (mm) |
| N E U | N E U |
---------------|---------------------------|---------------------------|
cod 209 | -0.8 -0.1 0.3 | 2.2 1.7 5.2 |
emr 84 | -0.6 0.1 0.1 | 2.7 2.2 6.1 |
esa 122 | -0.7 -0.1 0.3 | 3.5 2.4 6.1 |
gfz 196 | -0.5 -0.1 0.1 | 2.1 2.1 5.2 |
jpl 103 | -1.1 -0.0 0.2 | 3.1 3.7 6.6 |
mit 222 | -0.0 0.0 0.1 | 1.9 2.0 4.6 |
ngs 197 | -0.3 -0.1 0.2 | 2.4 3.0 6.4 |
sio 251 | -0.2 0.1 0.6 | 2.7 1.9 5.4 |
grg 105 | -1.0 -0.3 0.1 | 4.1 3.2 6.1 |
mig 326 | -0.8 0.0 -0.1 | 2.3 2.2 5.1 |
igs 327 | -0.6 -0.0 -0.1 | 2.1 2.1 4.7 |
ITR 116 | -0.8 -0.1 -0.1 | 2.9 3.2 11.9 |
---------------|---------------------------|---------------------------|
5-3) 7-Parameters Transformation: AC ----> IGS05.snx
=========================================================
5-3-1) Estimates:
====================
Solution | R X R Y R Z T X T Y T Z SCL |
| (mas) (mas) (mas) (mm) (mm) (mm) (ppb) |
---------------|---------------------------------------------------------------|
cod | -0.017 0.001 -0.035 0.1 1.4 0.8 -0.03 |
emr | -0.017 0.065 -0.029 10.2 -0.9 7.2 0.26 |
esa | 0.060 -0.072 -0.027 10.2 2.5 -0.0 0.08 |
gfz | 0.004 0.034 -0.053 -0.7 1.0 0.9 0.01 |
jpl | 0.009 -0.026 0.001 9.9 2.9 7.5 0.37 |
mit | -0.002 0.004 -0.033 10.8 -5.6 5.9 -0.07 |
ngs | -0.073 -0.126 0.028 6.7 -4.2 1.2 0.07 |
sio | -0.110 0.267 -0.629 12.3 -1.7 13.4 0.14 |
grg | 0.012 0.024 -0.087 11.9 2.5 5.2 0.77 |
mig | -0.003 0.021 -0.013 -0.4 0.8 1.3 0.05 |
igs | 0.000 0.000 0.000 0.0 0.0 0.0 0.09 |
---------------|---------------------------------------------------------------|
5-3-2) STD:
==============
Solution | R X R Y R Z T X T Y T Z SCL |
| (mas) (mas) (mas) (mm) (mm) (mm) (ppb) |
---------------|---------------------------------------------------------------|
cod | 0.028 0.029 0.032 0.8 0.8 0.7 0.12 |
emr | 0.032 0.033 0.038 0.9 0.9 0.8 0.13 |
esa | 0.034 0.038 0.041 0.9 0.9 0.9 0.15 |
gfz | 0.030 0.030 0.033 0.8 0.8 0.8 0.12 |
jpl | 0.036 0.039 0.041 1.0 1.0 1.0 0.15 |
mit | 0.029 0.030 0.032 0.8 0.8 0.8 0.12 |
ngs | 0.029 0.030 0.032 0.8 0.8 0.7 0.12 |
sio | 0.029 0.030 0.032 0.8 0.8 0.8 0.12 |
grg | 0.032 0.034 0.038 0.9 0.9 0.8 0.13 |
mig | 0.028 0.028 0.030 0.7 0.7 0.7 0.11 |
igs | 0.000 0.000 0.000 0.0 0.0 0.0 0.14 |
---------------|---------------------------------------------------------------|
5-4) Geocenter:
====================
| X Y Z | s X s Y s Z |
| (mm) (mm) (mm) | (mm) (mm) (mm) |
---------------|---------------------------|---------------------------|
igs | 8.5 -5.0 6.1 | 1.2 1.1 3.2 |
---------------|---------------------------|---------------------------|
5-5) ERP Residuals Weighted Average & STD:
===============================================
5-5-1) Weighted Average:
===========================
Solution | UT LOD XPO XPOR YPO YPOR |
| us us .01mas .01ma/d .01mas .01ma/d |
---------------|------------------------------------------------------------|
cod | --- --- --- --- --- --- |
emr | --- 9.9 -0.6 13.7 0.5 1.7 |
esa | --- 11.9 -4.3 14.7 -3.7 -23.3 |
gfz | --- 0.6 -0.5 -7.3 -1.5 -17.1 |
jpl | --- 9.5 0.8 16.0 -4.1 12.8 |
mit | --- -2.6 -0.2 1.3 1.9 3.4 |
ngs | --- -2.3 2.6 7.0 -10.2 -8.7 |
sio | --- 23.1 1.2 4.6 0.6 19.8 |
grg | --- 1.9 -2.8 40.1 -4.0 -11.6 |
mig | --- 18.0 1.0 8.7 -1.9 19.8 |
BuA | --- 0.4 -1.6 17.1 -1.6 4.7 |
---------------|------------------------------------------------------------|
5-5-2) STD:
==============
Solution | UT LOD XPO XPOR YPO YPOR |
| us us .01mas .01ma/d .01mas .01ma/d |
---------------|------------------------------------------------------------|
cod | --- --- --- --- --- --- |
emr | --- 7.1 3.6 14.3 3.3 16.8 |
esa | --- 5.0 2.8 9.6 2.4 10.2 |
gfz | --- 1.3 2.8 5.3 2.1 12.0 |
jpl | --- 8.7 1.6 12.0 2.2 8.5 |
mit | --- 0.9 1.3 2.3 1.4 6.1 |
ngs | --- 5.7 2.1 7.2 8.0 12.7 |
sio | --- 1.0 1.2 3.2 0.6 4.1 |
grg | --- 26.8 3.2 15.5 5.2 19.4 |
mig | --- 1.0 1.2 3.0 0.6 3.9 |
BuA | --- 11.7 5.0 7.2 4.5 12.7 |
---------------|------------------------------------------------------------|
5-6) Satellite Antenna Offset Residuals weighted Average & STD:
====================================================================
No Satellite phase center ...
5-7) Outliers:
===================
Outliers may be rejected at different stages of the processing:
- During the combination (stage 3-4)), outliers may be removed from the
weekly AC solutions. Thresholds are set to 5 cm and 5 sigma.
- During stage 3-6), outliers may be removed from the AC solutions NOT
included in the combination. Thresholds are set to 5 cm and 5 sigma.
- During the stacking of the weekly combined solution on the cumulative
solution (stage 3-7)), outliers may be removed from the weekly
solution. Thresholds are set to 3 cm and 3 sigma.
Solution Stage of rejection | Station | N E U |
|code id soln| (mm) (mm) (mm)|
-----------------------------------------|------------|-----------------------|
| | |
cod15767.snx Combination: Iter. 1 |OHI3 A 2| 4.3 0.8 -9.9|
mit15767.snx Combination: Iter. 1 |CONZ A 3| -5.6 -0.7 -1.4|
ngs15767.snx Combination: Iter. 1 |FAAA A 1| -2.7 16.4 -1.7|
ngs15767.snx Combination: Iter. 1 |THTI A 1| -2.4 16.0 -3.8|
sio15767.snx Combination: Iter. 1 |OHI3 A 2| -0.2 -1.7 17.9|
mit15767.snx Combination: Iter. 2 |OHI2 A 1| -5.0 1.0 3.7|
| | |
grg15767.snx Comp. to igs10P1576.snx |CONZ A 3| -3.3 98.8 7.7|
| | |
-----------------------------------------|------------|-----------------------|
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