Subject: [IGSREPORT-8785] Wk 1138 IGS SINEX Combination
From: Remi Ferland <[email-masked]>
To: [email-masked] (IGS Report Mailbox)
Date: Thu, 15 Nov 2001 17:43:16 EST

******************************************************************************
IGS Electronic Report   15 Nov 14:43:19 PST 2001      Message Number 8785
******************************************************************************

Author:  R. Ferland

===================================================================
 Combined AC  solution for GPS week 1138 -  01/10/28 to 01/11/03
===================================================================

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

igs01P1138.snx  Combined weekly solution. 
igs01P1138.erp  Daily Earth Rotation Parameters.
igs00p02.erp    Daily Earth Rotation Parameters since GPS week 1013.
IGS01P44.snx    Cumulative Combined solution. 
igs01P1138.sum  This file.
igs01P1138.itr  Residuals between the AC and the IGS97 for the RF stations. 
igs01P1138.res  Residuals between the AC and the Combined Weekly solution.
IGS01P44.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 = igs01P1138.snx
     IGS = IGS01P44.snx

     BuA = IERS Bulletin A

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

     Solutions with manual station deletion:
         From the original solution:
             ITR  AREQ
         After unconstraining:
             emr  NRC1  NRC2
             ncl  KELY

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

     4-2) Starting with GPS week 1078, UT1-UTC from IERS Bulletin A
     is included in the erp files.

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            | 124 |  42 |        25.579 |         0.991 |        25.353 |
esa            |  53 |  35 |         9.972 |         1.001 |         9.977 |
emr            |  47 |  30 |         2.907 |         0.994 |         2.889 |
gfz            |  83 |  40 |         7.000 |         0.993 |         6.950 |
jpl            |  75 |  29 |         3.765 |         0.991 |         3.733 |
ngs            |  74 |  46 |        20.601 |         0.999 |        20.573 |
sio            | 145 |  46 |         1.723 |         0.998 |         1.719 |
mit            | 169 |  47 |         3.153 |         1.235 |         3.892 |
ncl            | 102 |  47 |         2.288 |         0.998 |         2.284 |
igs            | 154 |  49 |         1.308 |         1.055 |         1.380 |
---------------|-----|-----|---------------|---------------|---------------|

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         41 |     1.1      0.7     -2.1 |     3.7      5.2     11.6 |
esa         34 |    -2.9      0.4     -0.4 |     7.2      5.7     15.1 |
emr         29 |    -0.6      0.6      0.6 |     3.9      5.5     13.0 |
gfz         38 |    -0.2      0.2     -0.8 |     3.3      4.7     10.4 |
jpl         28 |    -0.7      0.4      0.9 |     3.9      4.5     10.9 |
ngs         45 |    -0.7      0.0     -0.4 |     5.6      7.4     13.6 |
sio         45 |     0.1      0.5     -2.0 |     3.4      4.9     11.0 |
mit         46 |     1.7      0.7     -1.5 |     3.2      4.6     10.1 |
ncl         46 |     0.6      0.3     -0.4 |     2.9      4.3      8.5 |
---------------|---------------------------|---------------------------|

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

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod        121 |     1.0      0.1     -0.8 |     2.3      2.6      7.6 |
esa         52 |    -2.8      1.0     -0.6 |     5.7      6.4     10.0 |
emr         45 |    -0.9      0.5      1.5 |     2.2      5.1      7.8 |
gfz         77 |    -1.1      0.2      1.9 |     1.8      1.8      5.2 |
jpl         70 |    -1.3      1.0      1.4 |     2.0      2.1      6.1 |
ngs         72 |    -1.6     -1.0     -0.3 |     4.7      5.6      8.9 |
sio        136 |    -0.6      0.1      1.1 |     1.8      1.9      5.0 |
mit        148 |     1.0      0.5     -0.2 |     0.9      0.9      3.7 |
ncl        100 |     0.0      0.0      1.8 |     0.7      0.6      3.1 |
ITR         48 |    -0.6     -0.3     -0.3 |     3.0      4.8     10.8 |
---------------|---------------------------|---------------------------|

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

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod        122 |     1.8      0.4     -2.3 |     3.3      4.1      8.5 |
esa         53 |    -2.3      1.0     -1.8 |     6.3      7.5     11.6 |
emr         46 |    -0.4      0.4      1.9 |     2.9      5.5     10.2 |
gfz         78 |    -0.3      0.3      0.3 |     3.3      3.2      9.7 |
jpl         71 |    -0.9      1.2      1.0 |     3.0      3.7      8.1 |
ngs         73 |    -0.7     -0.6     -1.4 |     5.3      6.5     11.4 |
sio        137 |    -0.1      0.5     -0.1 |     3.0      3.6      6.8 |
mit        150 |     1.8      0.8     -1.7 |     2.6      3.3      7.7 |
ncl        100 |     0.6      0.6      1.1 |     2.3      2.4      5.7 |
igs        154 |     0.6      0.4     -1.4 |     2.3      2.4      6.0 |
ITR         50 |    -0.2     -0.1     -0.3 |     1.9      2.8      7.6 |
---------------|---------------------------|---------------------------|

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            |   0.000   -0.038   -0.007      0.6      0.0     -2.6     2.57 |
esa            |   0.056    0.006   -0.026    -13.5     29.6      4.7     2.59 |
emr            |   0.055   -0.038   -0.040      0.8      2.9    -59.4     1.98 |
gfz            |   0.002   -0.020   -0.007     -0.6     -0.0     -4.4     2.49 |
jpl            |  -0.027   -0.006   -0.095      9.0     13.8    -44.4     1.99 |
ngs            |  -0.109   -0.141    0.030     15.5     -5.7     18.8     3.40 |
sio            |  -0.082    0.024    0.148     10.8      3.0     62.9     2.81 |
mit            |  -0.016   -0.009   -0.042      0.5     -0.9     -2.0     2.46 |
ncl            |   0.021   -0.092   -0.013      2.2      1.4     -7.3     1.99 |
---------------|---------------------------------------------------------------|

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            |   0.062    0.062    0.071      1.6      1.6      1.6     0.25 |
esa            |   0.069    0.069    0.075      1.8      1.8      1.8     0.28 |
emr            |   0.075    0.071    0.083      1.9      1.9      1.9     0.29 |
gfz            |   0.064    0.064    0.073      1.7      1.7      1.7     0.26 |
jpl            |   0.075    0.071    0.083      1.9      1.9      1.9     0.30 |
ngs            |   0.059    0.060    0.067      1.6      1.6      1.5     0.24 |
sio            |   0.060    0.059    0.067      1.5      1.5      1.5     0.24 |
mit            |   0.059    0.059    0.067      1.5      1.5      1.5     0.24 |
ncl            |   0.059    0.059    0.066      1.5      1.5      1.5     0.24 |
---------------|---------------------------------------------------------------|

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

               |      X        Y        Z  |    s X      s Y      s Z  |
               |    (mm)     (mm)     (mm) |    (mm)     (mm)     (mm) |
---------------|---------------------------|---------------------------|
igs            |     9.0      4.4    -20.0 |     1.8      2.0      6.9 |
---------------|---------------------------|---------------------------|

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            |     ---        -.4     -18.1      -2.4      -2.2        .1 |
esa            |     ---      -11.6      -7.7      -3.7     -23.9      -2.2 |
emr            |     ---      -11.2       1.3      17.1       5.7      -2.5 |
gfz            |     ---        9.1       2.0       1.7      10.4       -.9 |
jpl            |     ---        1.1       1.5      11.7        .4       4.1 |
ngs            |     ---      112.0     -27.9      45.8      26.3     -74.5 |
sio            |     ---        -.4       9.7      -2.2       3.3       1.0 |
mit            |     ---        5.7        .2       -.7        .5        .1 |
ncl            |     ---        ---       ---       ---       ---       --- |
ITR            |     ---        ---       ---       ---       ---       --- |
BuA            |     ---      -14.3      -8.4       1.1      32.9       4.3 |
---------------|------------------------------------------------------------|

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

Solution       |      UT       LOD       XPO      XPOR       YPO      YPOR  |
               |      us        us    .01mas    .01ma/d   .01mas    .01ma/d |
---------------|------------------------------------------------------------|
cod            |     ---        6.5       3.0      12.8       4.0       7.5 |
esa            |     ---       10.9       4.9      12.0       5.0      16.0 |
emr            |     ---        6.7       7.6      22.4       6.4      28.4 |
gfz            |     ---       12.4       3.3      15.4       3.7       5.7 |
jpl            |     ---       23.7       1.8      17.8       4.8      16.6 |
ngs            |     ---       32.0      10.8      66.5      11.4      80.1 |
sio            |     ---        6.6       3.9       5.6       2.3       4.2 |
mit            |     ---        2.8       1.0       3.9       1.1       1.8 |
ncl            |     ---        ---       ---       ---       ---       --- |
ITR            |     ---        ---       ---       ---       ---       --- |
BuA            |     ---       16.6       4.1       6.7       5.4       8.6 |
---------------|------------------------------------------------------------|

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    jpl11387.snx        |LHAS  A ----|   -0.6    12.7    11.7|
                                         |            |                       |
cod11387.snx         esa11387.snx        |RIOG  A ----|    7.8     0.2    50.9|
                                         |            |                       |
jpl11387.snx         mit1138g.snx        |KELY  A ----|    0.4     4.2    63.4|
                                         |            |                       |
igs01P1137.snx       gfz11387.snx        |THU1  A ----|    2.4     3.2    55.7|
                                         |            |                       |
IGS01P43.snx         cod11387.snx        |HOFN  A ----|    8.2    -6.3   -52.7|
                                         |            |                       |
IGS01P43.snx         gfz11387.snx        |GOUG  A ----|   -6.5     1.8    71.1|
                                         |            |                       |
IGS01P43.snx         sio11387.snx        |HERS  A ----|   -0.5    14.5    19.5|
IGS01P43.snx         sio11387.snx        |HOFN  A ----|    6.8    -4.7   -49.7|
IGS01P43.snx         sio11387.snx        |WHIT  A ----|    1.9    -2.5   -22.4|
                                         |            |                       |
IGS01P43.snx         ncl1138g.snx        |COCO  A ----|    6.8   -20.3     4.8|
IGS01P43.snx         ncl1138g.snx        |HOFN  A ----|    8.7    -5.4   -46.9|
                                         |            |                       |
IGS01P43.snx         igs01P1138.snx      |COCO  A ----|    6.4   -19.7     1.0|
-----------------------------------------|------------|-----------------------|

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

IERS DOMES NO    cod    emr    esa    gfz    jpl    ngs    sio    IGS    igs
============= ====== ====== ====== ====== ====== ====== ====== ====== ======
    22003M001 PIMO A        PIMO B PIMO A PIMO A        PIMO A PIMO A PIMO A
    42005M001 GALA A GALA A GALA B GALA A GALA A GALA B GALA A GALA A GALA A
    22306M002 IISC A IISC A IISC B IISC A IISC A IISC B IISC A IISC A IISC A
    13407S012 MADR A               MADR A MADR A MADR A MAD2 A MADR A MADR A
    40114M001 NRC1 A NRC1 A NRC1 A        NRC1 A        NRC1 A NRC1 A NRC1 A
                     NRC2 A 
    40405S031 GOLD A               GOLD A        GOL2 A GOL2 A GOLD A GOLD A
    30314M002 SUTH A SUTH A SUTH B SUTH A        SUTH A SUTH A SUTH A SUTH A
    50107M004 YAR1 A YAR1 A YAR1 A YAR1 A YAR1 A YAR1 A YAR1 A YAR1 A YAR1 A
                                          YAR2 A
    20705M001                                           BSHM A BSHM 2 BSHM 2
 
MISSING IERS DOMES NOS AT gfz:
-----------------------------
  BISH A
 
MISSING IERS DOMES NOS AT sio:
-----------------------------
  CAVA A  SFEL A  VOLT A
 
IERS DOMES NO    mit    ncl    IGS    igs
============= ====== ====== ====== ======
    13407S012 MADR A MADR A MADR A MADR A
              MAD2 A 
    31303M001 MAS1 A 
    31303M002        MAS1 A MAS1 A MAS1 A
    43005M001 KELY A        KELY A KELY A
    43005M002        KELY A
    40114M001 NRC1 A NRC1 A NRC1 A NRC1 A
              NRC2 A 
    40405S031 GOLD A        GOLD A GOLD A
              GOL2 A 
    50107M004 YAR1 A YAR1 A YAR1 A YAR1 A
              YAR2 A 
    12309M001 MDVO A 
    12309M002               MDVO A MDVO A
    20705M001 BSHM A        BSHM 2 BSHM 2
 
MISSING IERS DOMES NOS AT mit:
-----------------------------
  BISH A
 
--