Subject: [IGSREPORT-4211] Wk 0923 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Wed, 8 Oct 1997 12:19:01 PDT

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IGS Electronic Report    Wed Oct  8 12:19:01 PDT 1997      Message Number 4211
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0923 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0923   
(SEP 14, 1997 - SEP 20, 1997)

Contacts: J. Kouba ([email-masked])
          D. Hutchison([email-masked])

COMPARISON ALGORITHM:

   1. MIT and NCL GNAAC  combined  SINEX  solutions  for the week in question
      were deconstrained. The JPL SINEX file is already unconstrained.

   2. Any stations  not  present  in  all GNAAC combined SINEX files were de-
      leted  from all three combined solutions.  Every solution was then sub-
      jected to a 7-parameter transformation  into  a common reference system
      (the 13 ITRF94 station positions). 

   3. Outliers are determined at the 99.0% confidence level for each coordin-
      ate.  If a station  has  an outlier in either latitude,  longitude,  or
      height, it is ignored in all subsequent computations.

FILES COMPARED:
   mit0923g.snx at cddis.gsfc.nasa.gov
   jpl0923g.snx at cddis.gsfc.nasa.gov
   ncl0923g.snx at cddis.gsfc.nasa.gov

GNAACs: MIT JPL NCL

STATIONS WITH INCONSISTENT ANTENNA ECCENTRICITY INFORMATION:
(FILE: / STATION / L1 (UNE) / L2 (UNE) / ECCENTRICITY (UNE))
(UNE = Up North East (metres))

jpl0923g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0923g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
jpl0923g.snx: GALA    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0923g.snx: GALA    .110   .000   .000   .128   .000   .000   .082   .000   .000
jpl0923g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0923g.snx: HARK    .110   .000   .000   .128   .000   .000  9.803   .000   .000
ncl0923g.snx: HARK    .110   .000   .000   .128   .000   .000  9.803   .000   .000
jpl0923g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0923g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
jpl0923g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0923g.snx: LPGS    .110   .000   .000   .128   .000   .000   .046   .000   .000
ncl0923g.snx: LPGS    .110   .000   .000   .128   .000   .000   .046   .000   .000
jpl0923g.snx: MDVO    .078   .000  -.003   .074  -.003  -.001   .146   .000   .000
mit0923g.snx: MDVO    .078   .000  -.003   .074  -.003  -.001   .146   .000   .000
ncl0923g.snx: MDVO    .078   .000  -.003   .074  -.003  -.001   .149   .000   .000
jpl0923g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0923g.snx: NICO    .110   .000   .000   .128   .000   .000   .050   .000   .000
jpl0923g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0923g.snx: SELE    .110   .000   .000   .128   .000   .000   .090   .000   .000
jpl0923g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
mit0923g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
ncl0923g.snx: TAEJ    .078   .000  -.003   .074  -.003  -.001   .660   .000   .000
jpl0923g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0923g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
jpl0923g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0923g.snx: ZIMM    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000

ANTENNA PHASE CENTRE CONFLICTS IN FILE mit0923g.snx                             
   KSTU Multiple Sites      
   ZWEN Multiple Sites      
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: KSTU ZWEN 
 
ANTENNA PHASE CENTRE CONFLICTS IN FILE ncl0923g.snx                             
   ASC1 Missing Antenna      
   AUCK Missing Antenna      
   CHAT Missing Antenna      
   DGAR Missing Antenna      
   KIRU Missing Antenna      
   KWJ1 Missing Antenna      
   MKEA Missing Antenna      
   VILL Missing Antenna      
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: ASC1 AUCK CHAT DGAR KIRU KWJ1 MKEA VILL 

CONFIDENCE  LEVEL  FOR OUTLIER DETECTION: 99%
OUTLIERS REJECTED (COORD/STATION/GNAACs):
   Lat KERG JPL-NCL   Lat HOB2 MIT-NCL   Lon MALI MIT-JPL
   Lon MALI MIT-NCL   Hgt MCM4 JPL-NCL   Hgt MCM4 MIT-JPL
   Hgt WUHN MIT-JPL   Hgt CAS1 MIT-NCL   Hgt MCM4 MIT-NCL
   Hgt WUHN MIT-NCL          

46 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ BAHR BOR1 BRAZ BRMU CRO1 DRAO
   FAIR FORT GOLD GUAM IISC IRKT KELY KIT3 KOKB KOSG
   KOUR LHAS MAC1 MATE MDO1 METS NLIB NRC1 ONSA PERT
   POL2 POTS RCM6 REYK SANT SHAO STJO TAHI TAIW TIDB
   TSKB USUD WES2 WHIT WTZR YELL    

9 FIDUCIAL STATIONS:
   ALGO FAIR GOLD KOKB KOSG SANT TIDB WTZR YELL 

AVERAGE COORDINATE RMS:

             46    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        0.8       1.5       1.1        4.3        4.2        3.9 
Lon        1.7       2.3       2.8        6.5        6.9        7.5 
Hgt        3.4       2.9       2.4       10.3       10.6       10.8 
3D         3.8       4.0       3.9       12.9       13.3       13.7

VARIANCE FACTORS (CHI-SQUARE / (DEGREES OF FREEDOM)):

        46    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.150     0.813     0.248      1.175      0.991      1.070

OFFSETS AND SCALE FACTOR WRT ITRF94 (FIDUCIAL STATIONS):
(TRANSFORMATION FROM ITRF94 TO GNAAC SINEX FILES)

      Tx (mm) STD(mm) Ty (mm) STD(mm) Tz (mm) STD(mm) Scale (ppb) STD(ppb)
      ------- ------- ------- ------- ------- ------- ----------- --------
JPL      -1.1     4.2    14.5     4.4   -23.0     6.2        -1.5      0.5
MIT      -1.0     3.1    10.0     3.3   -20.5     3.6        -1.5      0.4
NCL       1.2     4.3    10.4     4.4    -7.6     6.2        -1.6      0.5

REMARKS:

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM mit0923g.snx :
   Stations: HART TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM jpl0923g.snx :
   Stations: TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM ncl0923g.snx :
   Stations: HART TROM

MADR, YAR1 WERE NOT USED IN GLOBAL COMPARISON DUE TO LARGE COORDINATE DIFFERENCES
WITH ITRF94, DESCRIBED BELOW:

STATION / GNAAC / LONGITUDE DIFFERENCE (mm.):
   MADR JPL -33.4
        MIT -30.5
        NCL -32.8

STATION / GNAAC / HEIGHT DIFFERENCE (mm.):
   MADR JPL 21.4
        MIT 19.0
        NCL 20.4

STATION / GNAAC / HEIGHT DIFFERENCE (mm.):
   YAR1 JPL -36.7
        MIT -31.3
        NCL -40.1

-- 
David Hutchison
Geodetic Survey of Canada
Ottawa, Ontario, Canada
Internet: [email-masked]

[Mailed From: David Hutchison <[email-masked]>]