Subject: [IGSREPORT-3679] WK 0899 G-SNX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Mon, 28 Apr 1997 12:33:32 PDT

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IGS Electronic Report    Mon Apr 28 12:33:32 PDT 1997      Message Number 3679
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Author: AC Coordinator / NRCan GSDivision
Subject: WK 0899 G-SNX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0899   
(MAR 30, 1997 - APR 5, 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:
   mit0899g.snx at cddis.gsfc.nasa.gov
   jpl0899g.snx at cddis.gsfc.nasa.gov
   ncl0899g.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))

jpl0899g.snx: ANKR    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0899g.snx: ANKR    .110   .000   .000   .128   .000   .000   .060   .000   .000
ncl0899g.snx: ANKR    .110   .000   .000   .128   .000   .000   .060   .000   .000
jpl0899g.snx: BAHR    .000   .000   .000   .000   .000   .000  3.122   .000   .000
mit0899g.snx: BAHR    .110   .000   .000   .128   .000   .000  3.122   .000   .000
jpl0899g.snx: BISH    .070   .000   .000   .068   .000   .000   .046   .000   .000
mit0899g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
jpl0899g.snx: DRAO    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0899g.snx: DRAO    .110   .000   .000   .128   .000   .000   .100   .000   .000
ncl0899g.snx: DRAO    .110   .000   .000   .128   .000   .000   .100   .000   .000
jpl0899g.snx: GOPE    .070   .000   .000   .068   .000   .000   .046   .000   .000
mit0899g.snx: GOPE    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
jpl0899g.snx: GRAZ    .110   .000   .000   .128   .000   .000  1.964   .000   .000
mit0899g.snx: GRAZ    .110   .000   .000   .128   .000   .000  1.946   .000   .000
jpl0899g.snx: HART    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0899g.snx: HART    .078   .000   .000   .096   .000   .000  9.754   .000   .000
ncl0899g.snx: HART    .110   .000   .000   .128   .000   .000  9.754   .000   .000
jpl0899g.snx: HRAO    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0899g.snx: HRAO    .110   .000   .000   .128   .000   .000   .081   .000   .000
jpl0899g.snx: IISC    .110   .000   .000   .128   .000   .000   .078   .000   .000
mit0899g.snx: IISC    .110   .000   .000   .128   .000   .000   .078   .000   .000
ncl0899g.snx: IISC    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0899g.snx: JOZE    .070   .000   .000   .068   .000   .000   .198   .000   .000
mit0899g.snx: JOZE    .069   .000  -.003   .068  -.003  -.001   .198   .000   .000
jpl0899g.snx: MATE    .110   .000   .000   .128   .000   .000   .101   .000   .000
mit0899g.snx: MATE    .110   .000   .000   .128   .000   .000   .066   .000   .000
ncl0899g.snx: MATE    .110   .000   .000   .128   .000   .000   .101   .000   .000
jpl0899g.snx: MONP    .000   .000   .000   .000   .000   .000   .119   .000   .000
mit0899g.snx: MONP    .110   .000   .000   .128   .000   .000   .119   .000   .000
jpl0899g.snx: TAEJ    .000   .000   .000   .000   .000   .000   .660   .000   .000
mit0899g.snx: TAEJ    .069   .002  -.001   .068  -.001   .002   .660   .000   .000
jpl0899g.snx: UPAD    .070   .000   .000   .068   .000   .000  1.962   .000   .000
mit0899g.snx: UPAD    .078   .000  -.003   .074  -.003  -.001  1.962   .000   .000
jpl0899g.snx: UPO1    .110   .000   .000   .128   .000   .000   .078   .000   .000
mit0899g.snx: UPO1    .092  -.001   .000   .060   .000  -.001   .000   .000   .000
jpl0899g.snx: USUD    .078   .000   .000   .096   .000   .000  -.035   .000   .000
mit0899g.snx: USUD    .110   .000   .000   .128   .000   .000  -.035   .000   .000
ncl0899g.snx: USUD    .110   .000   .000   .128   .000   .000  -.035   .000   .000
jpl0899g.snx: WHIT    .110   .000   .000   .128   .000   .000   .100   .000   .000
mit0899g.snx: WHIT    .110   .000   .000   .128   .000   .000   .010   .000   .000
jpl0899g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0899g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
ncl0899g.snx: YAR1    .000   .000   .000   .000   .000   .000   .073   .000   .000
jpl0899g.snx: ZIMM    .070   .000   .000   .068   .000   .000   .000   .000   .000
mit0899g.snx: ZIMM    .069   .000  -.003   .068  -.003  -.001   .000   .000   .000

ANTENNA PHASE CENTRE CONFLICTS IN FILE mit0899g.snx                             
   MDVO Multiple Sites
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: MDVO 
 
ANTENNA PHASE CENTRE CONFLICTS IN FILE ncl0899g.snx                             
   ASC1 Missing Antenna      
   AUCK Missing Antenna      
   CHAT Missing Antenna      
   DGAR Missing Antenna      
   KWJ1 Missing Antenna      
   MKEA Missing Antenna      
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: ASC1 AUCK CHAT DGAR KWJ1 MKEA YAR1 

CONFIDENCE  LEVEL  FOR OUTLIER DETECTION: 99%
OUTLIERS REJECTED (COORD/STATION/GNAACs):
   Lat MCM4 JPL-NCL   Lat BRAZ JPL-NCL   Lat SANT JPL-NCL
   Lon COCO JPL-NCL   Lon PAMA JPL-NCL   Lon PAMA MIT-JPL
   Lon COCO MIT-JPL   Hgt IRKT JPL-NCL   Hgt CRO1 JPL-NCL
   Hgt IRKT MIT-JPL   Hgt WUHN MIT-NCL     

40 GLOBAL STATIONS:
   ALBH ALGO BOR1 BRMU CAS1 DAV1 FAIR FORT GOLD GUAM
   HART HOB2 KELY KERG KIT3 KOKB KOSG KOUR LHAS MAC1
   MALI MDO1 METS NLIB NYAL ONSA PERT POTS RCM6 REYK
   SHAO STJO TAIW TIDB TSKB WES2 WTZR YAR1 YELL ZWEN

10 FIDUCIAL STATIONS:
   ALGO FAIR GOLD HART KOKB KOSG TIDB WTZR YAR1 YELL

AVERAGE COORDINATE RMS:

             40    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.9       1.4       3.0        5.7        6.1        5.5 
Lon        1.9       1.4       2.4        8.2        8.1        7.6 
Hgt        3.6       2.4       4.9        8.7        8.5       10.0 
3D         4.5       3.1       6.2       13.2       13.2       13.8

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

        40    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.587     0.708     0.242      0.548      0.404      0.531

OFFSETS AND SCALE FACTOR WRT ITRF94 (FIDUCIAL STATIONS):

      Tx (mm) STD(mm) Ty (mm) STD(mm) Tz (mm) STD(mm) Scale (ppb) STD(ppb)
      ------- ------- ------- ------- ------- ------- ----------- --------
JPL       2.8     5.2    13.9     5.4   -50.0     7.1        -2.7      0.6
MIT       0.6     4.3    13.2     4.4   -44.2     5.1        -2.4      0.6
NCL       2.5     5.0    23.8     5.2   -26.9     6.5        -2.1      0.6

REMARKS:

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM mit0899g.snx :
   Stations: TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM ncl0899g.snx :
   Stations: TROM

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

LONGITUDE RMS AT 11 FIDUCIAL STATIONS HIGHER THAN USUAL. FOLLOWING
STATIONS HAVE LONGITUDE DIFFERENCES WITH ITRF94 IN EXCESS OF 4 CM.:
   Stations: MADR 

STATION / GNAAC / LONGITUDE DIFFERENCE (mm.):
   MADR JPL  56.5
        MIT  56.8
        NCL  49.0

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

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