[IGSREPORT-4127] Wk 0918 G-SINEX Comparisons

[AC]

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IGS Electronic Report    Fri Sep 12 14:05:15 PDT 1997      Message Number 4127
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0918 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0918   
(AUG 10, 1997 - AUG 16, 1997)

Contacts: J. Kouba (kouba at geod.emr.ca)
          D. Hutchison(hutch at geod.emr.ca)

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:
   mit0918g.snx at cddis.gsfc.nasa.gov
   jpl0918g.snx at cddis.gsfc.nasa.gov
   ncl0918g.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))

jpl0918g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0918g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
jpl0918g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0918g.snx: HARK    .110   .000   .000   .128   .000   .000  9.802   .000   .000
ncl0918g.snx: HARK    .110   .000   .000   .128   .000   .000  9.803   .000   .000
jpl0918g.snx: MDVO    .078   .000  -.003   .074  -.003  -.001   .146   .000   .000
mit0918g.snx: MDVO    .078   .002  -.003   .074  -.003  -.001   .146   .000   .000
ncl0918g.snx: MDVO    .078   .000  -.003   .074  -.003  -.001   .149   .000   .000
jpl0918g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0918g.snx: SELE    .110   .000   .000   .128   .000   .000   .089   .000   .000
jpl0918g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
mit0918g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
ncl0918g.snx: TAEJ    .078   .000  -.003   .074  -.003  -.001   .660   .000   .000
jpl0918g.snx: USUD    .110   .000   .000   .128   .000   .000  -.035   .000   .000
mit0918g.snx: USUD    .078   .000   .000   .096   .000   .000  -.035   .000   .000
ncl0918g.snx: USUD    .110   .000   .000   .128   .000   .000  -.035   .000   .000
jpl0918g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0918g.snx: ZIMM    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000

 
ANTENNA PHASE CENTRE CONFLICTS IN FILE ncl0918g.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      
   XIAN Missing Antenna      
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: ASC1 AUCK CHAT DGAR KIRU KWJ1 MKEA VILL XIAN 

CONFIDENCE  LEVEL  FOR OUTLIER DETECTION: 99%
OUTLIERS REJECTED (COORD/STATION/GNAACs):
   Lat SANT MIT-NCL   Hgt CRO1 JPL-NCL   Hgt MCM4 JPL-NCL
   Hgt MCM4 MIT-JPL   Hgt FORT MIT-JPL   Hgt CRO1 MIT-JPL
   Hgt CRO1 MIT-NCL          

50 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ BAHR BOR1 BRAZ BRMU BRUS CAS1
   COCO DAV1 DRAO FAIR GOLD GUAM HOB2 IISC IRKT KELY
   KERG KIT3 KOKB KOSG KOUR MAC1 MALI MATE MDO1 METS
   NLIB ONSA PERT POL2 POTS RCM6 REYK SHAO STJO TAHI
   TAIW TIDB TSKB WES2 WHIT WTZR WUHN YAR1 YELL ZWEN

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


AVERAGE COORDINATE RMS:

             50    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.0       1.1       1.1        5.7        5.6        5.8 
Lon        1.4       2.1       1.7        9.5        8.8        9.4 
Hgt        4.6       4.4       1.9        9.5       10.3       10.4 
3D         4.9       4.9       2.8       14.6       14.7       15.2


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

        50    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.090     1.233     0.261      1.646      1.222      1.328

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      -4.6     4.2    14.5     4.5   -25.8     5.8        -2.1      0.5
MIT      -6.8     3.0    13.7     3.2   -27.6     3.5        -2.0      0.4
NCL       0.3     4.6    20.1     5.0   -15.8     6.6        -2.0      0.5

REMARKS:

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM mit0918g.snx :
   Stations: HART TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM jpl0918g.snx :
   Stations: TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM ncl0918g.snx :
   Stations: HART TROM

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

STATION / GNAAC / LONGITUDE DIFFERENCE (mm.):
   MADR JPL -32.4
        MIT -30.0
        NCL -32.8


-- 
David Hutchison
Geodetic Survey of Canada
Ottawa, Ontario, Canada
Internet: hutch at geod.emr.ca


[Mailed From: David Hutchison <hutch at geod.emr.ca>]