Subject: [IGSREPORT-4558] Wk 0929 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Mon, 2 Feb 1998 12:52:10 PST

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IGS Electronic Report    Mon Feb  2 12:52:10 PST 1998      Message Number 4558
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0929 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0929   
(OCT 26, 1997 - NOV 1, 1997)

Contacts: J. Kouba ([email-masked])
          D. Hutchison ([email-masked])
          R. Ferland ([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:
   mit0929g.snx at cddis.gsfc.nasa.gov
   jpl0929g.snx at cddis.gsfc.nasa.gov
   ncl0929g.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))

jpl0929g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0929g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
   - Unresolvable (no log file)

jpl0929g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0929g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
   - Unresolvable (no log file)

jpl0929g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0929g.snx: HARK    .078   .000   .000   .096   .000   .000  9.803   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 9.8030 M.

jpl0929g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0929g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
   - Unresolvable (no log file)

jpl0929g.snx: KOUR    .078   .000   .000   .096   .000   .000   .132   .000   .000
mit0929g.snx: KOUR    .110   .000   .000   .128   .000   .000   .045   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.045 M.

jpl0929g.snx: MALI    .078   .000   .000   .096   .000   .000   .222   .000   .000
mit0929g.snx: MALI    .110   .000   .000   .128   .000   .000   .100   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.135 M.

jpl0929g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0929g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
   - Unresolvable (no log file)

jpl0929g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
mit0929g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.285   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 2.355 M.

jpl0929g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0929g.snx: YAR1    .078   .000   .000   .096   .000   .000   .081   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.081 M.

ncl0929g.snx: FORT    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0929g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
ncl0929g.snx: MDVO    Antenna missing.                          .146   .000   .000
jpl0929g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0929g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0929g.snx: ZECK    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0929g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000

FILE ncl0929g.snx MISSING THE SITE/GPS_PHASE_CENTER BLOCK.
DEFAULTING TO KNOWN L1/L2 OFFSETS AND ECCENTRICITIES.

CONFIDENCE LEVEL FOR OUTLIER DETECTION (ITRF94): 99%
OUTLIERS REJECTED (COORD/STATION/GNAACs):
   Lat KERG MIT-JPL   Lat CAS1 MIT-JPL   Lat COCO MIT-JPL
   Lat TAEJ MIT-JPL   Lat KERG MIT-NCL   Lat CAS1 MIT-NCL
   Lon NTUS MIT-JPL   Lon MADR MIT-JPL   Lon NTUS MIT-NCL
   Lon MADR MIT-NCL   Lon AUCK MIT-NCL   Hgt CAS1 MIT-JPL
   Hgt TAEJ MIT-JPL   Hgt CAS1 MIT-NCL   Hgt TAEJ MIT-NCL

59 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ ASC1 BAHR BOR1 BRMU BRUS CHAT
   CRO1 DGAR DRAO FAIR FLIN GOLD GUAM HOB2 IISC IRKT
   KELY KIRU KIT3 KOKB KOSG KSTU KWJ1 LHAS MAC1 MAS1
   MATE MCM4 MDO1 METS MKEA NLIB NRC1 ONSA PERT POL2
   POTS RCM6 REYK SANT SHAO STJO TAHI THU1 TIDB TSKB
   USUD VILL WES2 WHIT WSRT WTZR YAR1 YELL ZWEN 

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

AVERAGE COORDINATE RMS USING ITRF94:

             59    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.4       1.1       0.7        6.6        7.3        6.9 
Lon        1.9       1.9       0.6        7.9        7.9        7.8 
Hgt        5.5       5.8       1.1        9.6        8.9        8.9 
3D         6.0       6.2       1.5       14.1       13.9       13.8

VARIANCE FACTORS WITH ITRF94 (CHI-SQUARE / (DEGREES OF FREEDOM)):

        59    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.049     1.873     0.947      1.384      1.140      1.028

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      -7.7     4.8     2.1     4.9   -28.2     6.3        -1.5      0.4
MIT      -7.7     2.9     0.5     3.0   -36.6     3.6        -1.0      0.4
NCL      -6.5     4.5     8.2     4.5   -23.6     6.7        -1.5      0.4

REMARKS:

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM mit0929g.snx :
   Stations: HART TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM jpl0929g.snx :
   Stations: TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM ncl0929g.snx :
   Stations: HART TROM

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

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