Subject: [IGSREPORT-3953] Wk 0909 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Thu, 17 Jul 1997 7:06:35 PDT

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IGS Electronic Report    Thu Jul 17  7:06:35 PDT 1997      Message Number 3953
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0909 G-SINEX Comparisons

Subject: Wk 0909 G-SNX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0909   
(JUN 8, 1997 - JUN 14, 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:
   mit0909g.snx at cddis.gsfc.nasa.gov
   jpl0909g.snx at cddis.gsfc.nasa.gov
   ncl0909g.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))

jpl0909g.snx: HRAO    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0909g.snx: HRAO    .110   .000   .000   .128   .000   .000   .081   .000   .000
jpl0909g.snx: JOZE    .078   .000  -.003   .074  -.003  -.001   .198   .000   .000
mit0909g.snx: JOZE    .069   .000  -.003   .068  -.003  -.001   .198   .000   .000
jpl0909g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
mit0909g.snx: TAEJ    .069   .002  -.001   .068  -.001   .002   .660   .000   .000
jpl0909g.snx: TAHI    .110   .000   .000   .128   .000   .000  1.055   .000   .000
mit0909g.snx: TAHI    .110   .000   .000   .128   .000   .000  1.055   .000   .000
ncl0909g.snx: TAHI    .110   .000   .000   .128   .000   .000  1.023   .000   .000
jpl0909g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0909g.snx: ZIMM    .069   .000  -.003   .068  -.003  -.001   .000   .000   .000

ANTENNA PHASE CENTRE CONFLICTS IN FILE mit0909g.snx                             
   AREQ Multiple Sites     
   MDVO Multiple Sites
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: AREQ MDVO 
 
ANTENNA PHASE CENTRE CONFLICTS IN FILE ncl0909g.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 

CONFIDENCE  LEVEL  FOR OUTLIER DETECTION: 99%
OUTLIERS REJECTED (COORD/STATION/GNAACs):
   Lat CAS1 MIT-JPL   Lat DAV1 MIT-JPL   Lon MADR JPL-NCL
   Lon KOKB JPL-NCL   Lon WUHN MIT-JPL   Lon MADR MIT-NCL
   Lon KOKB MIT-NCL   Lon WUHN MIT-NCL   Hgt CRO1 JPL-NCL
   Hgt CRO1 MIT-JPL   Hgt WUHN MIT-JPL   Hgt WUHN MIT-NCL

48 GLOBAL STATIONS:
   ALBH ALGO ANKR BAHR BOR1 BRAZ BRMU COCO DRAO FAIR
   FORT GOLD GUAM HOB2 IISC IRKT KELY KERG KIT3 KOSG
   LHAS MAC1 MALI MATE MCM4 MDO1 METS NLIB NYAL ONSA
   PERT POL2 POTS RCM6 REYK SANT SHAO STJO TAIW TIDB
   TSKB USUD WES2 WHIT WTZR YAR1 YELL ZWEN  

9 FIDUCIAL STATIONS:
   ALGO FAIR GOLD KOSG SANT TIDB WTZR YAR1 YELL 

AVERAGE COORDINATE RMS:

             48    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.9       1.3       1.3        6.6        6.6        6.6 
Lon        1.6       2.2       1.4        9.4        9.8       10.1 
Hgt        2.9       3.1       2.7       12.5       11.6       11.7 
3D         3.8       4.1       3.3       17.0       16.6       16.8

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

        48    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.119     0.325     0.181      1.973      1.424      1.438

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      -5.6     4.5    22.6     4.6   -32.1     7.7        -1.3      0.5
MIT      -4.9     3.1    14.5     3.1   -29.8     4.2        -1.5      0.4
NCL      -6.0     4.7    29.5     4.7   -31.4     8.4        -1.4      0.5

REMARKS:

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM mit0909g.snx :
   Stations: HART TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM jpl0909g.snx :
   Stations: TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM ncl0909g.snx :
   Stations: HART TROM

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

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