Subject: [IGSREPORT-4246] Wk 0924 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Fri, 17 Oct 1997 6:28:49 PDT

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IGS Electronic Report    Fri Oct 17  6:28:49 PDT 1997      Message Number 4246
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0924 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0924   
(SEP 21, 1997 - SEP 27, 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:
   mit0924g.snx at cddis.gsfc.nasa.gov
   jpl0924g.snx at cddis.gsfc.nasa.gov
   ncl0924g.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))

jpl0924g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0924g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
jpl0924g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0924g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
jpl0924g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0924g.snx: HARK    .110   .000   .000   .128   .000   .000  9.803   .000   .000
ncl0924g.snx: HARK    .110   .000   .000   .128   .000   .000  9.803   .000   .000
jpl0924g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0924g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
jpl0924g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0924g.snx: LPGS    .110   .000   .000   .128   .000   .000   .046   .000   .000
ncl0924g.snx: LPGS    .110   .000   .000   .128   .000   .000   .046   .000   .000
jpl0924g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0924g.snx: NICO    .110   .000   .000   .128   .000   .000   .050   .000   .000
jpl0924g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0924g.snx: SELE    .110   .000   .000   .128   .000   .000   .090   .000   .000
jpl0924g.snx: SOFI    .110   .000   .000   .128   .000   .000   .000   .000   .000
mit0924g.snx: SOFI    .110   .000   .000   .128   .000   .000   .220   .000   .000
jpl0924g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
mit0924g.snx: TAEJ    .075   .002  -.001   .069  -.001   .002   .660   .000   .000
ncl0924g.snx: TAEJ    .078   .000  -.003   .074  -.003  -.001   .660   .000   .000
jpl0924g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0924g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
jpl0924g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0924g.snx: YAR1    .078   .000   .000   .096   .000   .000   .081   .000   .000
ncl0924g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
jpl0924g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0924g.snx: ZIMM    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000

ANTENNA PHASE CENTRE CONFLICTS IN FILE mit0924g.snx                             
   NTUS Multiple Sites      
   KSTU Multiple Sites      
   ZWEN Multiple Sites      
 
SITES AFFECTED BY ABOVE CONFLICTS, NON-FIDUCIAL SITES SUBSEQUENTLY EXCLUDED:
   Stations: NTUS KSTU ZWEN 
 
ANTENNA PHASE CENTRE CONFLICTS IN FILE ncl0924g.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 KERG MIT-JPL   Lat TAHI MIT-JPL   Hgt MCM4 JPL-NCL
   Hgt MCM4 MIT-JPL   Hgt TAHI MIT-NCL     

49 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ BAHR BOR1 BRAZ BRMU CAS1 CRO1
   DRAO FAIR FORT GOLD GUAM HOB2 IISC IRKT KELY KIT3
   KOKB KOSG KOUR LHAS MAC1 MALI MATE MDO1 METS ONSA
   PERT POL2 POTS RCM6 REYK SANT SHAO STJO TAIW TIDB
   TSKB USUD WES2 WHIT WSRT WTZR WUHN YAR1 YELL 

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

AVERAGE COORDINATE RMS:

             49    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        0.9       0.9       1.0        6.6        6.5        6.4 
Lon        1.8       1.5       1.4        7.3        6.8        7.0 
Hgt        3.4       3.8       2.5       12.6       12.5       12.5 
3D         4.0       4.1       3.0       16.0       15.6       15.7

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

        49    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.127     0.826     0.291      1.792      1.559      1.361

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      -5.8     3.9     5.3     4.0   -11.3     5.8        -1.3      0.4
MIT      -5.7     2.7     4.0     2.8   -14.7     3.2        -1.2      0.4
NCL      -3.2     4.2    10.7     4.4    -7.0     6.1        -1.3      0.4

REMARKS:

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM mit0924g.snx :
   Stations: HART TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM jpl0924g.snx :
   Stations: TROM

THE FOLLOWING FIDUCIAL STATIONS ARE MISSING FROM ncl0924g.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 -32.5
        MIT -31.1
        NCL -33.0

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

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