Subject: [IGSREPORT-6276] Wk 1015 Preliminary IGS SINEX Combination
From: R. Ferland , D. Hutchison
Date: Sat, 17 Jul 1999 12:34:00 PDT

******************************************************************************
IGS Electronic Report    Sat Jul 17 12:34:00 PDT 1999      Message Number 6276
******************************************************************************

Author: R. Ferland , D. Hutchison
Subject: Wk 1015 Preliminary IGS SINEX Combination

===================================================================
 Combined AC  solution for GPS week 1015 -  99/06/20 to 99/06/26
===================================================================

1) Contacts:
============
e-mail: [email-masked]
Tel:    (613)995-4002 (Remi Ferland)
Fax:    (613)995-3215

2) Products:
============
All products are available at cddisa.gsfc.nasa.gov

igs99P1015.snx  Combined weekly solution. 
igs99P1015.erp  Daily Earth Rotation Parameters.
IGS99P25.snx    Cumulative Combined solution. 
igs99P1015.sum  This file.
igs99P1015.itr  Residuals between the AC and the ITRF96 for the RF stations.
igs99P1015.res  Residuals between the AC and the Combined Weekly solution.
IGS99P25.res    Residuals between the AC and the Cumulative Combined solution.
 
Where IGSyyPww & igsyyPwwww represent:
      yy      Last 2 digits of the year
      ww      week in year yy
      wwww    GPS week
      P       GPS technique used

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) The AC solutions are unconstrained according to the information provided
     in the SOLUTION/APRIORI Block.
3-3) The AC solutions are aligned (using a 7-parameters) and compared to the
     ITRF96 Reference Frame (RF) stations at the current epoch.
     ftp://igscb.jpl.nasa.gov/igscb/station/coord/ITRF96_IGS_RS47.SNX.Z
3-4) The AC are compared to ITRF, to each other, to the previous week
     solution and to the cumulative solution in order to identify and remove
     outliers.
3-5) The weekly AC solutions are combined and added to the cumulative
     combined solution. The cumulative combination is done to ensures 14
     parameters singularity.

     The weekly combined solution is aligned to the ITRF96 of the current
     epoch using a 7-parameters transformation. The singular cumulative
     combined solution is aligned to the ITRF96 of the reference epoch
     using a 14-parameters transformation and the 47 ITRF station positions
     and velocities.

     For more details, see:
     Blewitt, G., C. Boucher and J. Kouba, 1997, Procedure for ITRF continuous
       realization, the report of the IGS GB, presented to the IGS Governing 
       Board Meeting held in San Francisco, Dec. 11.
     Kouba, J., J. Ray and M.M. Watkins, IGS Reference Frame Realization, 1998
       IGS Analysis Center Workshop Proceedings, European Space Operations
       Centre, Darmstadt, Germany.

The combination software was developed at NRCan.

4) Remarks:
===========

     igs = igs99P1012.snx
     IGS = IGS99P22.snx

     JPL = jpl1015g.snx
     jpl = jpl10157.snx

     ITR = ITRF96_IGS_RS47.SNX
     itr = ITRF97 with the current 47 Reference Frame stations plus
           AUCK BAHR CAS1 CHAT MCM4.
     JPL ncl mit itr are used to quality control the weekly combination.
     emr gfz ngs sio excluded from the geocenter estimation (Sec. 5-4).
     mit matrix was not used.

5) Results:
===========

5-1)      AC (Variance Factor)^0.5 estimates:
==================================================
           The residuals used in the estimation of the Variance Factor
           are the differences between the cumulative combined solution
           and each AC weekly solution.
           SF = (Variance Factor)^0.5 = (Chi^2/dof)^0.5
           Final(SF) = Apriori(SF) * Aposteriori(SF)

Solution       |# sta| #RF |    Apriori(SF)|Aposteriori(SF)|      Final(SF)|
---------------|-----|-----|---------------|---------------|---------------|
cod            | 120 |  39 |        35.243 |         0.996 |        35.093 |
emr            |  43 |  25 |         6.060 |         1.002 |         6.074 |
esa            |  57 |  35 |         7.663 |         1.000 |         7.665 |
gfz            |  67 |  33 |        23.677 |         0.992 |        23.498 |
jpl            |  55 |  21 |         4.657 |         1.017 |         4.737 |
ngs            |  73 |  42 |        40.852 |         0.997 |        40.725 |
sio            | 124 |  38 |         1.492 |         0.998 |         1.489 |
JPL            | 128 |  40 |         2.600 |         1.036 |         2.695 |
ncl            |  86 |  38 |         2.939 |         0.986 |         2.899 |
mit            | 148 |  39 |         3.563 |         1.001 |         3.567 |
itr            |  52 |  48 |        10.000 |         0.344 |         3.438 |
---------------|-----|-----|---------------|---------------|---------------|

5-2)      Solution Residuals weighted Average & R.M.S. :
========================================================

5-2-1)    With respect to ITRF96 Reference Frame stations:
=========================================================

Solution       |  Weighted Average (mm)    |        R.M.S. (mm)        |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod            |     2.1     -1.2      0.3 |     5.0      8.4     11.8 |
emr            |    -1.5     -1.8     -0.4 |     8.2     14.5     14.2 |
esa            |     2.3      0.2      0.2 |     6.9     11.7     14.6 |
gfz            |     0.5     -0.9      0.4 |     6.2      6.6     11.3 |
jpl            |     2.0     -0.1     -0.5 |     6.1      8.4      7.1 |
ngs            |     0.6     -0.1      0.3 |    10.0     12.0     14.3 |
sio            |    -0.9     -0.8      0.0 |     4.6      9.1     10.9 |
JPL            |     1.3     -0.3      0.6 |     5.0      7.1      9.5 |
ncl            |     0.8     -0.6      0.3 |     4.5      5.3      6.0 |
mit            |     1.0     -0.6      0.4 |     4.3      5.8      6.0 |
itr            |    -0.3      0.0     -0.5 |     4.3      6.4      9.4 |
---------------|---------------------------|---------------------------|

5-2-2)    With respect to Weekly Combination:
============================================

Solution       |  Weighted Average (mm)    |        R.M.S. (mm)        |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod            |     1.9     -1.1      0.2 |     3.1      4.1     12.0 |
emr            |    -1.7     -3.7      1.4 |     6.8     10.8     12.4 |
esa            |     1.5     -2.2      0.3 |     4.7      6.8     10.7 |
gfz            |     0.2     -0.7      0.4 |     2.8      2.3      8.8 |
jpl            |     2.1     -3.4     -0.8 |     5.2      4.4      6.8 |
ngs            |    -1.5      0.8     -0.9 |     8.6     16.0     12.9 |
sio            |    -1.4     -1.2     -0.3 |     2.6      3.5      4.1 |
JPL            |     0.9     -0.4      1.0 |     1.5      1.9      6.3 |
ncl            |     0.6     -0.8      0.2 |     2.1      2.0      5.4 |
mit            |     0.6     -0.9     -0.3 |     1.9      4.6      5.9 |
itr            |    -0.8      0.2     -0.6 |     3.5      5.4      8.6 |
ITR            |    -0.5      0.9     -0.1 |     5.1     10.1      9.8 |
---------------|---------------------------|---------------------------|

5-2-3)    With respect to Cumulative Combination:
================================================

Solution       |  Weighted Average (mm)    |        R.M.S. (mm)        |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod            |     1.7     -0.8     -1.1 |     4.3      4.3     14.8 |
emr            |    -1.6     -2.9      0.3 |     7.2     11.1     13.8 |
esa            |     2.4     -2.1     -0.8 |     7.2      7.5     11.1 |
gfz            |     0.8     -0.4     -1.0 |     3.0      3.4     12.4 |
jpl            |     3.2     -2.5     -2.7 |     5.2      4.4     11.6 |
ngs            |    -0.5      0.7     -1.2 |     8.3     17.0     15.0 |
sio            |    -1.4     -0.7     -1.4 |     3.8      4.2      9.2 |
JPL            |     1.0      0.0     -0.1 |     3.1      3.1     10.4 |
ncl            |     1.0     -0.5     -0.7 |     2.6      2.4     10.4 |
mit            |     0.7     -0.5     -1.3 |     3.6      3.6     10.4 |
itr            |     0.4      0.3     -1.0 |     2.8      3.2      9.6 |
igs            |     0.2      0.4     -0.9 |     3.1      3.4      8.0 |
ITR            |     0.5      0.9     -0.9 |     5.7      7.9     13.8 |
---------------|---------------------------|---------------------------|

5-3)      7-Parameters Transformation: AC ----> ITRF96_IGS_RS47.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            |  -0.065    0.028   -0.021      4.8     -0.7     26.7     1.56 |
emr            |  -0.007    0.036    0.040     -0.8    -66.8    225.4     0.57 |
esa            |  -0.021    0.011    0.078    -20.2     -8.5     12.4    -1.08 |
gfz            |  -0.001    0.075    0.023     -0.4     -0.0      2.0    -0.92 |
jpl            |   0.073    0.044    0.116      2.6      1.8     -5.7     0.90 |
ngs            |   0.036   -0.007   -0.127      3.1      8.2      9.1    -0.82 |
sio            |   0.025    0.294    0.266     -2.4    -11.4     74.6     0.01 |
JPL            |  -0.014   -0.022    0.001      0.2      0.4     -0.0    -0.01 |
ncl            |   0.034   -0.008    0.062      1.9      0.5     -0.5     0.05 |
mit            |  -0.024    0.020    0.049      0.5     -1.1     -0.9     0.29 |
itr            |  -0.162    0.263    0.056     -0.4     -0.6     14.7    -1.45 |
---------------|---------------------------------------------------------------|

5-3-2)    Sigmas : 
==================

Solution       |    R X      R Y      R Z      T X      T Y      T Z      SCL  |
               |   (mas)    (mas)    (mas)     (mm)     (mm)     (mm)    (ppb) |
---------------|---------------------------------------------------------------|
cod            |   0.067    0.071    0.069      1.8      1.8      1.7     0.27 |
emr            |   0.085    0.083    0.089      2.2      2.2      2.1     0.33 |
esa            |   0.070    0.070    0.075      1.8      1.8      1.8     0.28 |
gfz            |   0.075    0.076    0.076      2.0      1.9      1.9     0.30 |
jpl            |   0.092    0.090    0.096      2.3      2.4      2.3     0.36 |
ngs            |   0.066    0.069    0.068      1.7      1.7      1.7     0.26 |
sio            |   0.068    0.072    0.070      1.8      1.8      1.7     0.27 |
JPL            |   0.066    0.071    0.069      1.8      1.8      1.7     0.27 |
ncl            |   0.069    0.074    0.070      1.8      1.8      1.8     0.28 |
mit            |   0.068    0.069    0.072      1.8      1.8      1.7     0.27 |
itr            |   0.060    0.062    0.064      1.6      1.6      1.6     0.24 |
---------------|---------------------------------------------------------------|

5-4)      Geocenter:
====================

               |      X        Y        Z  |    s X      s Y      s Z  |
               |    (mm)     (mm)     (mm) |    (mm)     (mm)     (mm) |
---------------|---------------------------|---------------------------|
igs            |    -3.6     -2.5     -0.6 |     5.2      5.1      7.5 |
---------------|---------------------------|---------------------------|

5-5)      ERP Residuals Weighted Average & R.M.S. :
===================================================

5-5-1)    Weighted Average :
============================

Solution       |      UT       LOD       XPO      XPOR       YPO      YPOR  |
               |      us        us    .01mas    .01ma/d   .01mas    .01ma/d |
---------------|------------------------------------------------------------|
cod            |     ---        2.7     -20.7       1.9       4.5      -6.5 |
emr            |     ---         .9       1.7      92.6      -2.6     -21.3 |
esa            |     ---        1.8     -10.4      -1.2       7.9       6.0 |
gfz            |     ---      -17.4       -.5       -.7      -1.1      -2.8 |
jpl            |     ---        1.6     -17.9     -11.7       7.5      10.7 |
ngs            |     ---       30.1     -45.8       2.8      17.9     -42.1 |
sio            |     ---        8.8     -10.3      10.4      -1.7       3.6 |
JPL            |     ---        ---       ---       ---       ---       --- |
ncl            |     ---        ---       ---       ---       ---       --- |
mit            |     ---      -11.3     -16.2        .0     -11.2      -1.4 |
itr            |     ---        ---       ---       ---       ---       --- |
ITR            |     ---        ---       ---       ---       ---       --- |
---------------|------------------------------------------------------------|

5-5-2)    R.M.S. :
==================

Solution       |      UT       LOD       XPO      XPOR       YPO      YPOR  |
               |      us        us    .01mas    .01ma/d   .01mas    .01ma/d |
---------------|------------------------------------------------------------|
cod            |     ---        7.9      21.7      15.8      10.1      15.3 |
emr            |     ---       14.1       6.2      95.1       8.2      31.7 |
esa            |     ---       27.0      11.5      30.6      20.3      60.2 |
gfz            |     ---       20.7       3.9       9.3       6.1      15.9 |
jpl            |     ---       32.2      18.6      20.7       8.3      13.9 |
ngs            |     ---      153.2      47.1      52.4      21.3      68.9 |
sio            |     ---       15.6      11.1      12.3       5.2       6.6 |
JPL            |     ---        ---       ---       ---       ---       --- |
ncl            |     ---        ---       ---       ---       ---       --- |
mit            |     ---       12.9      16.3       4.3      11.5       6.0 |
itr            |     ---        ---       ---       ---       ---       --- |
ITR            |     ---        ---       ---       ---       ---       --- |
---------------|------------------------------------------------------------|

5-6)      Outliers:
===================

Threshold set at 5 sigmas

 Solution             Solution           |  Station   |    N       E       U  |
              Minus                      |code id soln|   (mm)    (mm)    (mm)|
-----------------------------------------|------------|-----------------------|
                                         |            |                       |
ITRF96_IGS_RS47.snx  esa10157.snx        |MADR  A ----|   15.7   -36.0    32.7|
                                         |            |                       |
ITRF96_IGS_RS47.snx  esa10157.snx        |GODE  A ----|   -1.6   -26.8   -27.2|
                                         |            |                       |
ITRF96_IGS_RS47.snx  jpl10157.snx        |MADR  A ----|   24.8   -41.5    19.7|
                                         |            |                       |
ITRF96_IGS_RS47.snx  sio10157.snx        |MADR  A ----|   15.6   -35.6    22.7|
                                         |            |                       |
ITRF96_IGS_RS47.snx  JPL1015g.snx        |MADR  A ----|   16.7   -37.6    26.3|
                                         |            |                       |
ITRF96_IGS_RS47.snx  JPL1015g.snx        |GODE  A ----|    1.6   -17.5   -17.1|
ITRF96_IGS_RS47.snx  JPL1015g.snx        |MAC1  A ----|    6.4    23.1     7.4|
                                         |            |                       |
ITRF96_IGS_RS47.snx  ncl1015g.snx        |GODE  A ----|    1.2   -15.0    -5.6|
ITRF96_IGS_RS47.snx  ncl1015g.snx        |MAC1  A ----|    1.7    20.0     3.9|
                                         |            |                       |
ITRF96_IGS_RS47.snx  mit1015g.snx        |MADR  A ----|   16.5   -39.3    22.9|
                                         |            |                       |
ITRF96_IGS_RS47.snx  mit1015g.snx        |GODE  A ----|    1.2   -15.9   -12.5|
                                         |            |                       |
IGS99P24.snx         JPL1015g.snx        |YAKA  A ----|  -21.8     7.7   -20.8|
                                         |            |                       |
IGS99P24.snx         igs99P1015.snx      |CHAT  A ----|   10.3     1.5    -2.7|
IGS99P24.snx         igs99P1015.snx      |MADR  A ----|   20.7   -26.0    -2.9|
IGS99P24.snx         igs99P1015.snx      |YAKA  A ----|  -21.7     8.0   -19.6|
-----------------------------------------|------------|-----------------------|

5-7)      Conflicts:
====================

[Mailed From: Remi Ferland <[email-masked]>]