Subject: [IGSREPORT-3955] Wk 0911 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Thu, 17 Jul 1997 7:10:18 PDT

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IGS Electronic Report    Thu Jul 17  7:10:18 PDT 1997      Message Number 3955
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0911 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0911   
(JUN 22, 1997 - JUN 28, 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:
   mit0911g.snx at cddis.gsfc.nasa.gov
   jpl0911g.snx at cddis.gsfc.nasa.gov
   ncl0911g.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))

jpl0911g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0911g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
jpl0911g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0911g.snx: HARK    .078   .000   .000   .096   .000   .000  9.803   .000   .000
jpl0911g.snx: HARV    .110   .000   .000   .128   .000   .000   .061   .000   .000
mit0911g.snx: HARV    .110   .000   .000   .128   .000   .000   .099   .000   .000
jpl0911g.snx: JOZE    .078   .000  -.003   .074  -.003  -.001   .198   .000   .000
mit0911g.snx: JOZE    .078   .000   .003   .074   .003   .001   .198   .000   .000
jpl0911g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
mit0911g.snx: TAEJ    .078   .002   .003   .074   .003   .001   .660   .000   .000
jpl0911g.snx: TAHI    .110   .000   .000   .128   .000   .000  1.055   .000   .000
mit0911g.snx: TAHI    .110   .000   .000   .128   .000   .000  1.054   .000   .000
ncl0911g.snx: TAHI    .110   .000   .000   .128   .000   .000  1.023   .000   .000
jpl0911g.snx: USUD    .110   .000   .000   .128   .000   .000  -.035   .000   .000
mit0911g.snx: USUD    .078   .000   .000   .096   .000   .000  -.035   .000   .000
ncl0911g.snx: USUD    .110   .000   .000   .128   .000   .000  -.035   .000   .000
jpl0911g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0911g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
ncl0911g.snx: YAR1    .000   .000   .000   .000   .000   .000   .073   .000   .000
jpl0911g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0911g.snx: ZIMM    .078   .000   .003   .074   .003   .001   .000   .000   .000

ANTENNA PHASE CENTRE CONFLICTS IN FILE mit0911g.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 ncl0911g.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 BAHR TAEJ YAR1 

CONFIDENCE  LEVEL  FOR OUTLIER DETECTION: 99%
OUTLIERS REJECTED (COORD/STATION/GNAACs):
   Lon GUAM JPL-NCL   Lon DAV1 MIT-JPL   Hgt MCM4 JPL-NCL
   Hgt CRO1 JPL-NCL   Hgt MCM4 MIT-JPL   Hgt CRO1 MIT-NCL
   Hgt MCM4 MIT-NCL          

44 GLOBAL STATIONS:
   ALBH ALGO BRAZ BRMU CAS1 COCO DRAO FAIR FLIN FORT
   GOLD HOB2 IISC IRKT KERG KIT3 KOKB KOSG LHAS MAC1
   MALI MATE MDO1 METS NLIB NYAL ONSA PERT POTS RCM6
   REYK SANT SHAO STJO TAIW TIDB TSKB WES2 WHIT WTZR
   WUHN YAR1 YELL ZWEN      

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

AVERAGE COORDINATE RMS:

             44    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.7       1.8       1.2        6.8        6.2        6.4 
Lon        1.9       1.3       1.9        9.4        7.4        9.1 
Hgt        5.1       3.6       5.0       13.7       10.7       13.9 
3D         5.7       4.3       5.5       18.0       14.4       17.8

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

        44    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.409     1.240     0.321      2.561      1.604      2.017

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      -1.6     3.3     8.8     3.2     6.7     3.1        -1.1      0.4
MIT      -6.1     2.9    24.8     3.0   -19.7     3.8        -1.5      0.4
NCL      -0.5     4.4    37.2     4.6    -9.5     6.5        -1.5      0.4

REMARKS:

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM mit0911g.snx :
   Stations: HART TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM jpl0911g.snx :
   Stations: HART TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM ncl0911g.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 -27.9
        MIT -28.8
        NCL -29.4

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

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