Subject: [IGSREPORT-7360] Wk 1068 IGS SINEX Combination
From: Remi Ferland <[email-masked]>
To: [email-masked] (IGS Report Mailbox)
Date: Thu, 13 Jul 2000 17:23:03 EDT

******************************************************************************
IGS Electronic Report   13 Jul 14:23:06 PDT 2000      Message Number 7360
******************************************************************************

Author:  R. Ferland

===================================================================
 Combined AC  solution for GPS week 1068 -  00/06/25 to 00/07/01
===================================================================

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

igs00P1068.snx  Combined weekly solution. 
igs00P1068.erp  Daily Earth Rotation Parameters.
igs00p02.erp    Daily Earth Rotation Parameters since GPS week 1013.
IGS00P26.snx    Cumulative Combined solution. 
igs00P1068.sum  This file.
igs00P1068.itr  Residuals between the AC and the IGS97 for the RF stations. 
igs00P1068.res  Residuals between the AC and the Combined Weekly solution.
IGS00P26.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
     IGS97 stations at the current epoch.
     ftp://igscb.jpl.nasa.gov/igscb/station/coord/IGS00P04_RS51.SNX.Z
3-4) The AC are compared to IGS97, 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 IGS97 of the current
     epoch using a 7-parameters transformation. The singular cumulative
     combined solution is aligned to the IGS97 of the reference epoch
     using a 14-parameters transformation and the 51 ITRF station positions
     and velocities. The IGS97 is a realization of ITRF97.

     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:
===========

     ITR = IGS00P04_RS51.SNX
     igs = igs00P1068.snx
     IGS = IGS00P26.snx

     JPL = jpl1068g.snx
     jpl = jpl10687.snx

     BuA = IERS Bulletin A

     JPL mit ncl are used to quality control the weekly combination.
     emr gfz ngs sio excluded from the geocenter estimation (Sec. 5-4).

     Solutions with manual station deletion:
         After unconstraining:
             esa  ZWEN
             gfz  ZWEN
             sio  ZWEN

     4-1) Starting with GPS week 1065, the solutions are aligned to the
     IGS00P04_RS51.SNX realization of ITRF97.

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            | 132 |  43 |        36.600 |         1.001 |        36.627 |
emr            |  49 |  29 |         3.102 |         0.999 |         3.099 |
esa            |  48 |  33 |        11.062 |         1.000 |        11.065 |
gfz            |  79 |  39 |        24.672 |         1.254 |        30.934 |
jpl            |  63 |  31 |         4.394 |         1.001 |         4.398 |
sio            | 139 |  43 |         2.378 |         1.000 |         2.378 |
JPL            | 144 |  45 |         2.840 |         1.001 |         2.843 |
mit            | 150 |  42 |         2.595 |         2.042 |         5.298 |
ncl            |  98 |  43 |         2.736 |         1.097 |         3.001 |
igs            | 135 |  45 |         1.510 |         0.982 |         1.483 |
---------------|-----|-----|---------------|---------------|---------------|

5-2)      Solution Residuals weighted Average & STD :
=====================================================

5-2-1)    With respect to the IGS97 stations:
=============================================

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod         42 |    -0.7      0.1      0.3 |     2.7      3.3     11.0 |
emr         28 |    -0.1      0.2      0.7 |     3.1      3.8     12.0 |
esa         32 |    -0.6     -0.4     -0.7 |     4.6      5.3     12.6 |
gfz         38 |     1.3     -0.1      0.0 |     3.0      3.0      9.6 |
jpl         30 |     0.2      0.4      0.1 |     2.6      4.4     11.1 |
sio         42 |     1.0     -0.2     -0.8 |     3.0      3.3      9.6 |
JPL         44 |     0.6      0.0      0.0 |     2.3      2.8      9.0 |
mit         41 |     0.8      0.6     -0.1 |     4.7      4.5      8.0 |
ncl         42 |     0.4      0.1     -0.1 |     2.7      3.1      7.2 |
---------------|---------------------------|---------------------------|

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

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod        125 |    -1.2      0.9      0.6 |     2.5      2.5      9.9 |
emr         47 |    -1.0      1.2      1.5 |     2.4      3.8      6.8 |
esa         48 |    -1.6     -1.0      1.5 |     4.4      4.9      9.6 |
gfz         73 |     1.0     -0.2     -0.4 |     2.0      2.0      6.5 |
jpl         59 |    -0.6     -0.2     -0.4 |     1.6      1.9      6.0 |
sio        125 |     0.6     -0.7     -0.1 |     1.8      2.4      5.1 |
JPL        134 |     0.1      0.1      0.7 |     1.1      0.7      5.3 |
mit        125 |    -0.4      1.4      1.0 |     2.0      1.9      4.1 |
ncl         93 |     0.1     -0.1      0.0 |     0.9      1.4      3.5 |
ITR         44 |    -0.6      0.0     -0.3 |     2.3      3.2      8.9 |
---------------|---------------------------|---------------------------|

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

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod        125 |    -1.2      1.0     -0.8 |     3.6      3.9     12.0 |
emr         48 |    -0.5      0.5      0.9 |     3.7      5.8     11.3 |
esa         48 |    -1.8      0.1      0.5 |     5.1      6.1     12.2 |
gfz         74 |     1.2     -0.9     -2.7 |     3.4      4.5     11.5 |
jpl         59 |    -0.5      0.2     -1.1 |     3.0      3.5     10.2 |
sio        126 |     0.7     -0.8     -1.5 |     3.2      4.7      7.8 |
JPL        134 |     0.0      0.1     -0.8 |     2.9      3.3     10.0 |
mit        126 |    -0.4      1.1     -0.7 |     4.0      3.7      8.3 |
ncl         93 |     0.0     -0.1     -1.4 |     2.8      3.3      8.5 |
igs        135 |     0.0      0.1     -1.4 |     2.7      3.2      7.5 |
ITR         51 |     0.0      0.1     -0.1 |     0.6      0.9      2.3 |
---------------|---------------------------|---------------------------|

5-3)      7-Parameters Transformation: AC ----> IGS00P04_RS51.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            |   0.038   -0.030    0.039      8.5     -5.6    -11.9     2.75 |
emr            |  -0.046   -0.054   -0.001     -0.5     -5.6    -12.0     1.75 |
esa            |  -0.013    0.041   -0.015     -7.9     23.6    -13.9     0.77 |
gfz            |  -0.073    0.001    0.075     -1.7      1.5     -3.0     1.33 |
jpl            |  -0.040   -0.046   -0.056      5.4     11.1    -23.2     2.07 |
sio            |  -0.048   -0.070    0.358      1.5     -0.2     25.5     1.87 |
JPL            |  -0.040   -0.020    0.054     -1.4      1.9     -4.8     2.02 |
mit            |   0.034   -0.019   -0.036     -0.0     -1.2     -0.6     1.94 |
ncl            |  -0.202    0.108   -0.286     12.7     -4.3     -8.3     1.60 |
---------------|---------------------------------------------------------------|

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            |   0.060    0.063    0.068      1.6      1.6      1.6     0.25 |
emr            |   0.074    0.074    0.084      1.9      1.9      1.9     0.30 |
esa            |   0.071    0.071    0.076      1.8      1.8      1.8     0.28 |
gfz            |   0.064    0.065    0.072      1.7      1.7      1.7     0.26 |
jpl            |   0.070    0.071    0.079      1.8      1.8      1.8     0.29 |
sio            |   0.061    0.062    0.068      1.6      1.6      1.6     0.25 |
JPL            |   0.059    0.061    0.067      1.6      1.5      1.5     0.24 |
mit            |   0.062    0.063    0.071      1.6      1.6      1.6     0.25 |
ncl            |   0.060    0.062    0.069      1.6      1.6      1.6     0.25 |
---------------|---------------------------------------------------------------|

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

               |      X        Y        Z  |    s X      s Y      s Z  |
               |    (mm)     (mm)     (mm) |    (mm)     (mm)     (mm) |
---------------|---------------------------|---------------------------|
igs            |     3.4      7.2    -17.0 |     7.3      7.3      9.6 |
---------------|---------------------------|---------------------------|

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            |     ---        3.5       2.3       2.5      -2.9       -.7 |
emr            |     ---       -2.5      -3.6      44.4      -9.0     -11.3 |
esa            |     ---       -5.2       2.3       3.6     -23.9      -1.0 |
gfz            |     ---      -16.2        .6      -5.3       8.4        .2 |
jpl            |     ---      -14.1        .1     -16.5       1.7       4.1 |
sio            |     ---       19.4        .3     -10.8       2.9      -7.7 |
JPL            |     ---        ---       ---       ---       ---       --- |
mit            |     ---        4.2       2.5       -.8      -3.3        .8 |
ncl            |     ---        ---       ---       ---       ---       --- |
ITR            |     ---        ---       ---       ---       ---       --- |
BuA            |     ---        9.8        .9       1.5      26.1      -2.2 |
---------------|------------------------------------------------------------|

5-5-2)    STD :
===============

Solution       |      UT       LOD       XPO      XPOR       YPO      YPOR  |
               |      us        us    .01mas    .01ma/d   .01mas    .01ma/d |
---------------|------------------------------------------------------------|
cod            |     ---        9.1       5.6       8.1       2.2       4.5 |
emr            |     ---       17.6       5.1      45.8       8.5      63.6 |
esa            |     ---       14.0       4.7      12.9       3.2      17.1 |
gfz            |     ---       10.1       2.9       5.1       3.8       4.8 |
jpl            |     ---       23.9       5.0      32.6       4.2      21.3 |
sio            |     ---       21.3       4.4      15.6       5.2      10.3 |
JPL            |     ---        ---       ---       ---       ---       --- |
mit            |     ---        8.2       2.0       1.3       1.3       3.6 |
ncl            |     ---        ---       ---       ---       ---       --- |
ITR            |     ---        ---       ---       ---       ---       --- |
BuA            |     ---        9.3       3.9       9.1       9.5      17.9 |
---------------|------------------------------------------------------------|

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

Thresholds set at 5 sigmas and 50 mm.

 Solution             Solution           |  Station   |    N       E       U  |
              Minus                      |code id soln|   (mm)    (mm)    (mm)|
-----------------------------------------|------------|-----------------------|
                                         |            |                       |
IGS00P04_RS51.snx    JPL1068g.snx        |ZWEN  A ----|   40.8   -46.2     0.2|
                                         |            |                       |
IGS00P04_RS51.snx    ncl1068g.snx        |ZWEN  A ----|   37.0   -43.0     8.7|
                                         |            |                       |
IGS00P25.snx         jpl10687.snx        |ARTU  A ----|   -0.2     0.4   -42.8|
IGS00P25.snx         jpl10687.snx        |COCO  A ----|    9.3   -28.4    19.2|
                                         |            |                       |
IGS00P25.snx         sio10687.snx        |ANKR  A ----|   -9.6    20.6   -15.5|
                                         |            |                       |
IGS00P25.snx         JPL1068g.snx        |COCO  A ----|    9.0   -28.2    -3.5|
                                         |            |                       |
IGS00P25.snx         mit1068g.snx        |ANKR  A ----|  -13.3    24.0   -13.4|
IGS00P25.snx         mit1068g.snx        |COCO  A ----|    7.2   -28.4     0.1|
IGS00P25.snx         mit1068g.snx        |MADR  A ----|    4.0    15.6    15.6|
                                         |            |                       |
IGS00P25.snx         ncl1068g.snx        |COCO  A ----|    8.0   -30.5     5.0|
                                         |            |                       |
igs00P1068.snx       mit1068g.snx        |METS  A ----|   -0.2     3.7    27.2|
                                         |            |                       |
IGS00P25.snx         igs00P1068.snx      |COCO  A ----|    7.1   -27.3    -4.5|
-----------------------------------------|------------|-----------------------|

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

IERS DOMES NO    cod    emr    esa    gfz    jpl    sio    IGS    igs
============= ====== ====== ====== ====== ====== ====== ====== ======
    50103M108 TID2 A        TID2 A TID2 A TID2 A TID2 A TIDB A TIDB A
    31303M002 MAS1 A MAS1 A MASP A MAS1 A        MAS1 A MAS1 A MAS1 A
    22306M002 IISC A        IISC B IISC A IISC A IISC A IISC A IISC A
    12353M001 YAKZ A                      YAKZ A YAKZ A YAKA A YAKA A
    42005M001 GALA A        GALA B GALA A GALA A GALA A GALA A GALA A
    13407S012 MAD2 A                             MAD2 A MADR A MADR A
    40114M001 NRC1 A NRC1 A                      NRC1 A NRC1 A NRC1 A
                     NRC2 A
    40405S031 GOL2 A        GOL2 A GOL2 A GOL2 A GOL2 A GOLD A GOLD A
 
MISSING IERS DOMES NOS AT gfz:
-----------------------------
  BISH A
IERS DOMES NO    JPL    mit    ncl    IGS    igs
============= ====== ====== ====== ====== ======
    40405S031 GOL2 A GOL2 A GOL2 A GOLD A GOLD A
    13407S012 MAD2 A MAD2 A        MADR A MADR A
    31303M002 MAS1 A        MAS1 A MAS1 A MAS1 A
    31303M001        MAS1 A 
    12309M002 MDVO A               MDVO A MDVO A
    12309M001        MDVO A 
    40114M001 NRC1 A NRC1 A NRC1 A NRC1 A NRC1 A
              NRC2 A NRC2 A 
    50103M108 TID2 A TID2 A TID2 A TIDB A TIDB A
    12353M001 YAKZ A YAKZ A YAKZ A YAKA A YAKA A
 
MISSING IERS DOMES NOS AT mit:
-----------------------------
  BISH A
--