Subject: [IGSREPORT-4565] Wk 0931 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Tue, 3 Feb 1998 9:01:14 PST

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IGS Electronic Report    Tue Feb  3  9:01:14 PST 1998      Message Number 4565
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0931 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0931   
(NOV 9, 1997 - NOV 15, 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:
   mit0931g.snx at cddis.gsfc.nasa.gov
   jpl0931g.snx at cddis.gsfc.nasa.gov
   ncl0931g.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))

jpl0931g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0931g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
   - Unresolvable (no log file)

jpl0931g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0931g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
   - Unresolvable (no log file)

jpl0931g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
mit0931g.snx: HARK    .110   .000   .000   .128   .000   .000  9.803   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 9.8030 M.

jpl0931g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0931g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
   - Unresolvable (no log file)

jpl0931g.snx: KOUR    .078   .000   .000   .096   .000   .000   .132   .000   .000
mit0931g.snx: KOUR    .078   .000   .000   .096   .000   .000   .045   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.045 M.

jpl0931g.snx: MALI    .078   .000   .000   .096   .000   .000   .222   .000   .000
mit0931g.snx: MALI    .078   .000   .000   .096   .000   .000   .135   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.135 M.

jpl0931g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0931g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
   - Unresolvable (no log file)

jpl0931g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
mit0931g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 2.355 M.

jpl0931g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0931g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.081 M.

jpl0931g.snx: CAGL    .110   .000   .000   .128   .000   .000   .000   .000   .000
ncl0931g.snx: FORT    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0931g.snx: HOFN    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0931g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0931g.snx: MOIN    .110   .000   .000   .128   .000   .000   .994   .000   .000
jpl0931g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0931g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0931g.snx: ZECK    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0931g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000

FILE ncl0931g.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 TAEJ MIT-JPL   Lat OHIG MIT-JPL   Lat COCO MIT-JPL
   Lat TAEJ MIT-NCL   Lat COCO MIT-NCL   Lat OHIG MIT-NCL
   Lon MAS1 JPL-NCL   Lon BRAZ MIT-JPL   Lon TAEJ MIT-JPL
   Lon AUCK MIT-JPL   Lon BRAZ MIT-NCL   Lon TAEJ MIT-NCL
   Lon AUCK MIT-NCL   Lon MAS1 MIT-NCL   Hgt TAEJ MIT-JPL
   Hgt TAEJ MIT-NCL          

60 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ ASC1 BAHR BOR1 BRMU CAS1 CHAT
   CRO1 DGAR DRAO FAIR FLIN GOLD GUAM IISC IRKT KELY
   KERG KIRU KIT3 KOKB KOSG KSTU KWJ1 LHAS MAC1 MADR
   MATE MCM4 MDO1 METS MKEA NLIB NTUS ONSA PERT POL2
   POTS RCM6 REYK SANT SHAO STJO TAHI TAIW THU1 TIDB
   TSKB USUD VILL WES2 WHIT WSRT WTZR YAR1 YELL ZWEN

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

AVERAGE COORDINATE RMS USING ITRF94:

             60    GLOBAL  STATIONS         11   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        0.9       1.0       0.5        9.4        9.1        9.0 
Lon        1.7       1.7       0.7       11.1       10.9       10.6 
Hgt        2.8       2.7       1.3       11.6       11.0       10.5 
3D         3.4       3.3       1.6       18.6       18.0       17.4

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

        60    GLOBAL  STATIONS         11   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.044     0.816     0.487      2.797      2.173      2.110

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      -9.5     4.5     1.6     4.7     5.4     6.1        -1.4      0.4
MIT     -11.7     2.7     1.5     2.8     0.2     3.2        -1.3      0.3
NCL      -9.2     4.4     5.1     4.5     5.5     6.5        -1.3      0.4

REMARKS:

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM mit0931g.snx :
   Stations: HART TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM jpl0931g.snx :
   Stations: TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM ncl0931g.snx :
   Stations: HART TROM

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

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