Subject: [IGSREPORT-9514] Wk 1177 IGS SINEX Combination
From: David Hutchison <[email-masked]>
To: [email-masked]
Date: Thu, 15 Aug 2002 20:15:59 EDT

******************************************************************************
IGS Electronic Report   15 Aug 17:16:02 PDT 2002      Message Number 9514
******************************************************************************

Author:  R. Ferland , D. Hutchison

===================================================================
 Combined AC  solution for GPS week 1177 -  02/07/28 to 02/08/03
===================================================================

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

igs02P1177.snx  Combined weekly solution. 
igs02P1177.erp  Daily Earth Rotation Parameters.
igs00p02.erp    Daily Earth Rotation Parameters since GPS week 1013.
IGS02P31.snx    Cumulative Combined solution. 
igs02P1177.sum  This file.
igs02P1177.itr  Residuals between the AC and the IGS00 for the RF stations. 
igs02P1177.res  Residuals between the AC and the Combined Weekly solution.
IGS02P31.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
     IGS00 stations at the current epoch.
     ftp://igscb.jpl.nasa.gov/igscb/station/coord/IGS01P37_RS54.SNX.Z
3-4) The AC are compared to IGS00, 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 IGS00 of the current
     epoch using a 7-parameters transformation. The singular cumulative
     combined solution is aligned to the IGS00 of the reference epoch
     using a 14-parameters transformation and the 54 ITRF station positions
     and velocities. The IGS00 is a realization of ITRF2000.

     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 = IGS01P37_RS54.SNX
     igs = igs02P1177.snx
     IGS = IGS02P31.snx

     BuA = IERS Bulletin A

     mit are used to quality control the weekly combination.
     gfz excluded from the geocenter estimation (Sec. 5-4).
     sio excluded pending resubmission. (Experienced transmission, content problems.)

     Solutions with manual station deletion:
         After unconstraining:
             jpl  KELY

     4-1) Starting with GPS week 1143, the solutions are aligned to the
     IGS01P37_RS54.SNX realization of ITRF2000.

     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            | 143 |  44 |        25.222 |         0.998 |        25.161 |
emr            |  41 |  23 |         4.462 |         0.997 |         4.447 |
esa            |  54 |  36 |        11.514 |         1.001 |        11.521 |
jpl            |  79 |  25 |         3.685 |         1.196 |         4.407 |
gfz            |  90 |  37 |         6.247 |         0.996 |         6.221 |
ngs            |  73 |  48 |        23.294 |         0.999 |        23.272 |
mit            | 170 |  47 |         2.798 |         1.051 |         2.940 |
igs            | 167 |  49 |         1.222 |         1.049 |         1.281 |
---------------|-----|-----|---------------|---------------|---------------|

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

5-2-1)    With respect to the IGS00 stations:
=============================================

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod         40 |     1.4      0.4      0.0 |     2.5      3.7     12.4 |
emr         22 |     0.8      0.5     -0.5 |     2.1      3.2      8.7 |
esa         31 |    -1.3     -0.3      0.3 |     5.9      4.3      8.0 |
jpl         24 |     0.4      0.3      0.0 |     2.3      1.9      8.7 |
gfz         35 |    -0.8      0.4     -1.4 |     2.6      3.4      9.1 |
ngs         46 |    -2.5      1.0     -0.3 |     5.7      4.9      8.6 |
mit         46 |    -0.2      0.2     -0.5 |     2.5      2.9      8.9 |
---------------|---------------------------|---------------------------|

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

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod        139 |     2.5      0.2      0.6 |     1.5      1.5      7.2 |
emr         39 |     1.9      0.4     -0.1 |     1.7      2.0      4.5 |
esa         53 |    -0.5     -1.5      0.9 |     5.9      5.1      7.3 |
jpl         77 |     1.6      0.9      0.7 |     1.5      1.4      5.0 |
gfz         87 |    -0.2      0.0      2.6 |     1.7      1.8      5.3 |
ngs         71 |    -2.2      0.2      1.2 |     4.4      4.5     10.4 |
mit        161 |     0.7     -0.1      1.4 |     0.8      0.7      4.0 |
ITR         48 |     0.3     -0.8      0.1 |     3.6      2.8      8.2 |
---------------|---------------------------|---------------------------|

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

Solution       |  Weighted Average (mm)    |          STD (mm)         |
               |      N        E        U  |      N        E        U  |
---------------|---------------------------|---------------------------|
cod        127 |     1.2      0.9     -3.3 |     2.5      3.0     12.7 |
emr         40 |     0.9      0.8     -3.3 |     1.6      2.9     10.6 |
esa         53 |    -1.5     -0.7     -0.5 |     6.3      4.5      8.1 |
jpl         66 |     0.7      1.2     -1.5 |     2.0      2.5      9.6 |
gfz         76 |    -1.3      0.4     -0.6 |     2.5      2.6      8.7 |
ngs         72 |    -2.9      0.8     -0.6 |     5.4      4.7      8.2 |
mit        138 |    -0.5      0.6     -2.1 |     2.1      2.3      9.8 |
igs        142 |    -1.1      0.6     -2.7 |     2.1      2.2      8.0 |
ITR         54 |    -0.2     -0.3      0.0 |     1.0      1.2      2.2 |
---------------|---------------------------|---------------------------|

5-3)      7-Parameters Transformation: AC ----> IGS01P37_RS54.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   -0.007   -0.017      8.8      8.1     -4.3     1.91 |
emr            |  -0.041   -0.055   -0.044     -0.3      5.5      6.1     1.10 |
esa            |   0.088    0.050   -0.054     -5.6      5.9      7.3     0.02 |
jpl            |  -0.007    0.005   -0.047     -3.1      9.3      1.4     0.89 |
gfz            |   0.000   -0.010    0.023     -0.0      1.8     -0.9     0.46 |
ngs            |   0.003    0.117   -0.030      6.4     -2.0     48.7     1.48 |
mit            |   0.015    0.011    0.013     -1.6      0.1     -0.5     1.21 |
---------------|---------------------------------------------------------------|

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            |   0.063    0.063    0.071      1.6      1.6      1.6     0.25 |
emr            |   0.083    0.084    0.097      2.2      2.2      2.2     0.34 |
esa            |   0.075    0.075    0.082      2.0      2.0      1.9     0.30 |
jpl            |   0.080    0.078    0.091      2.0      2.0      2.0     0.32 |
gfz            |   0.066    0.068    0.078      1.8      1.8      1.8     0.28 |
ngs            |   0.059    0.057    0.066      1.5      1.5      1.5     0.24 |
mit            |   0.057    0.058    0.067      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            |    -4.6      1.9      0.4 |     2.0      1.5      4.4 |
---------------|---------------------------|---------------------------|

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            |     ---        -.2      -1.1       ---      -8.2       --- |
emr            |     ---       -3.9      -2.1       7.0        .2      32.6 |
esa            |     ---        7.6      -8.6       ---     -26.6       --- |
jpl            |     ---      -23.6       3.2      -1.4       2.4       9.6 |
gfz            |     ---        5.5       -.4      -3.1       7.6      -1.3 |
ngs            |     ---      -40.3     -14.8      49.8       8.3     -76.8 |
mit            |     ---     -597.8       3.1      -1.2      -2.3        .4 |
ITR            |     ---        ---       ---       ---       ---       --- |
BuA            |     ---        3.3      -7.1        .3      22.6      -2.1 |
---------------|------------------------------------------------------------|

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

Solution       |      UT       LOD       XPO      XPOR       YPO      YPOR  |
               |      us        us    .01mas    .01ma/d   .01mas    .01ma/d |
---------------|------------------------------------------------------------|
cod            |     ---        6.5       4.4       ---       4.1       --- |
emr            |     ---        8.2       7.7      21.0       1.7      32.1 |
esa            |     ---        8.3       6.7       ---       6.2       --- |
jpl            |     ---       18.8       2.6      13.8       1.7      10.8 |
gfz            |     ---       10.8       3.6      10.0       2.8      11.9 |
ngs            |     ---       47.6      11.4      56.7      13.7      41.9 |
mit            |     ---      228.3       1.7       8.4       1.8      15.1 |
ITR            |     ---        ---       ---       ---       ---       --- |
BuA            |     ---       13.4       4.0      11.4       5.5      19.3 |
---------------|------------------------------------------------------------|

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

Thresholds set at 5 sigmas and 50 mm.

 Solution             Solution           |  Station   |    N       E       U  |
              Minus                      |code id soln|   (mm)    (mm)    (mm)|
-----------------------------------------|------------|-----------------------|
                                         |            |                       |
IGS01P37_RS54.snx    cod11777.snx        |GUAM  A ----|   18.5   -13.7    -6.7|
                                         |            |                       |
IGS01P37_RS54.snx    emr11777.snx        |GUAM  A ----|   18.0    -6.3     2.4|
                                         |            |                       |
IGS01P37_RS54.snx    esa11777.snx        |CHAT  A ----|   -1.5    -7.3   -84.6|
                                         |            |                       |
IGS01P37_RS54.snx    jpl11777.snx        |GUAM  A ----|   18.5    -7.1    15.2|
                                         |            |                       |
IGS01P37_RS54.snx    gfz11777.snx        |GUAM  A ----|   17.5    -8.9     9.7|
                                         |            |                       |
IGS01P37_RS54.snx    mit1177g.snx        |GUAM  A ----|   17.8   -10.6     5.8|
                                         |            |                       |
cod11777.snx         esa11777.snx        |NLIB  A ----|    4.9    -1.6   -51.8|
cod11777.snx         esa11777.snx        |RIOG  A ----|    6.2     1.3    58.4|
cod11777.snx         esa11777.snx        |SANT  A ----|    7.2     5.1    50.9|
                                         |            |                       |
cod11777.snx         ngs11777.snx        |NLIB  A ----|   -3.4    -2.0   -67.1|
                                         |            |                       |
esa11777.snx         gfz11777.snx        |KOKB  A ----|    3.9   -15.7    54.9|
                                         |            |                       |
jpl11777.snx         ngs11777.snx        |LAE1  A ----|   -0.8     0.8   -53.8|
                                         |            |                       |
IGS02P30.snx         cod11777.snx        |HOLM  A ----|   13.6    -3.4    61.4|
                                         |            |                       |
IGS02P30.snx         jpl11777.snx        |LHUE  A ----|   28.1   168.7   213.9|
                                         |            |                       |
IGS02P30.snx         jpl11777.snx        |ARTU  A ----|    0.9     0.0   -28.2|
IGS02P30.snx         jpl11777.snx        |SIO3  A ----|    3.7     4.0   -65.6|
                                         |            |                       |
IGS02P30.snx         mit1177g.snx        |LHUE  A ----|   27.8   169.6   208.1|
                                         |            |                       |
IGS02P30.snx         mit1177g.snx        |HOLM  A ----|   11.0    -4.2    60.6|
IGS02P30.snx         mit1177g.snx        |SIO3  A ----|    2.4     3.2   -69.8|
                                         |            |                       |
IGS02P30.snx         igs02P1177.snx      |IRKT  A ----|    0.1     0.6   -19.4|
IGS02P30.snx         igs02P1177.snx      |MBAR  A ----|    8.8     0.3    -0.1|
IGS02P30.snx         igs02P1177.snx      |URUM  A ----|   -3.6     3.9   -31.3|
-----------------------------------------|------------|-----------------------|

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

5-7-1) Station Name Conflicts:
============================= 

IERS DOMES NO    cod    emr    esa    gfz    jpl    ngs    IGS    igs
============= ====== ====== ====== ====== ====== ====== ====== ======
    42005M001 GALA A GALA A GALA B GALA A GALA A GALA B GALA A GALA A
    40405S031 GOLD A               GOLD A        GOL2 A GOLD A GOLD A
    22306M002 IISC A IISC A IISC B IISC A IISC A IISC B IISC A IISC A
    13407S012 MADR A               MADR A MAD2 A MADR A MADR A MADR A
    40114M001 NRC1 A NRC1 A NRC1 A                      NRC1 A NRC1 A
                     NRC2 A                                          
    30314M002 SUTH A        SUTH B SUTH A        SUTH A SUTH A SUTH A
    50103M108 TIDB A        TIDB A TIDB A TIDB A TID2 A TIDB A TIDB A
                            TID2 A                                   
    50107M004 YAR2 A                                    YAR1 A YAR1 A

IERS DOMES NO    mit    IGS    igs
============= ====== ====== ======
    13407S012 MADR A MADR A MADR A
              MAD2 A              
    40114M001 NRC1 A NRC1 A NRC1 A
              NRC2 A              
    40405S031 GOLD A GOLD A GOLD A
              GOL2 A              
    50103M108 TIDB A TIDB A TIDB A
              TID2 A              
    50107M004 YAR2 A YAR1 A YAR1 A

5-7-2) Station Antenna Conflicts:
================================ 

 _______________________ 
|Enforcing these aliases|
|_______________________|
   YAR1 A: YAR2 A  
   SUTH A: SUTH B  
   GALA A: GALA B  
   IISC A: IISC B  
   TIDB A: TID2 A  
   MADR A: MAD2 A  
   GOLD A: GOL2 A  

ABBREVIATIONS:
-------------
    L1: L1 Offset
    L2: L2 Offset
   ECC: Eccentricity
    -N: NORTH (Latitude) 
    -E: EAST  (Longitude)
    -U: UP    (Vertical) 

Compare to file IGS.SNX (IGS).                

Antenna Conflicts in file cod11777.snx (cod).           
------- --------- -- ---- 
    STN       L1-U   L1-N   L1-E   L2-U   L2-N   L2-E  ECC-U  ECC-N  ECC-E
AGY CODE PT   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)
=== ==== ==   ====   ====   ====   ====   ====   ====   ====   ====   ====
cod QAQ1  A  .1100  .0000  .0000  .1267 -.0003  .0002  .1206  .0000  .0000
IGS QAQ1  A  .1080 -.0002  .0001  .1267 -.0003  .0002  .1206  .0000  .0000

Antenna Conflicts in file esa11777.snx (esa).           
------- --------- -- ---- 
    STN       L1-U   L1-N   L1-E   L2-U   L2-N   L2-E  ECC-U  ECC-N  ECC-E
AGY CODE PT   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)
=== ==== ==   ====   ====   ====   ====   ====   ====   ====   ====   ====
esa NYAL  A  .0780  .0000  .0000  .0960  .0000  .0000 5.2160  .0000  .0000
IGS NYAL  A  .0780  .0000  .0000  .0960  .0000  .0000 5.2160  .0040 -.0010

Antenna Conflicts in file mit1177g.snx (mit).           
------- --------- -- ---- 
    STN       L1-U   L1-N   L1-E   L2-U   L2-N   L2-E  ECC-U  ECC-N  ECC-E
AGY CODE PT   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)
=== ==== ==   ====   ====   ====   ====   ====   ====   ====   ====   ====
mit NYAL  A  .0780  .0000  .0000  .0960  .0000  .0000 5.2160  .0000  .0000
IGS NYAL  A  .0780  .0000  .0000  .0960  .0000  .0000 5.2160  .0040 -.0010

Antenna Conflicts in file ngs11777.snx (ngs).           
------- --------- -- ---- 
    STN       L1-U   L1-N   L1-E   L2-U   L2-N   L2-E  ECC-U  ECC-N  ECC-E
AGY CODE PT   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)   (M.)
=== ==== ==   ====   ====   ====   ====   ====   ====   ====   ====   ====
ngs MCM4  A  .1100  .0000  .0000  .1280  .0000  .0000  .1830  .0000  .0000
IGS MCM4  A  .1100  .0000  .0000  .1280  .0000  .0000  .0814  .0000  .0000

ngs NYAL  A  .0780  .0000  .0000  .0960  .0000  .0000 5.2160  .0000  .0000
IGS NYAL  A  .0780  .0000  .0000  .0960  .0000  .0000 5.2160  .0040 -.0010

ngs WUHN  A  .1081  .0000  .0000  .1256  .0000  .0000 2.3200  .0000  .0000
IGS WUHN  A  .1100  .0000  .0000  .1280  .0000  .0000 2.3200  .0000  .0000

The following files have no antenna conflicts: 
   - emr11777.snx (emr)            
   - gfz11777.snx (gfz)            
   - jpl11777.snx (jpl)            
--