Subject: [IGSREPORT-4570] Wk 0937 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Tue, 3 Feb 1998 11:21:50 PST

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IGS Electronic Report    Tue Feb  3 11:21:50 PST 1998      Message Number 4570
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0937 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0937   
(DEC 21, 1997 - DEC 27, 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:
   mit0937g.snx at cddis.gsfc.nasa.gov
   jpl0937g.snx at cddis.gsfc.nasa.gov
   ncl0937g.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))

jpl0937g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0937g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
   - Unresolvable (no log file)

jpl0937g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0937g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
   - Unresolvable (no log file)

jpl0937g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0937g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
   - Unresolvable (no log file)

jpl0937g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0937g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
   - Unresolvable (no log file)

jpl0937g.snx: KOUR    .078   .000   .000   .096   .000   .000   .132   .000   .000
mit0937g.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.

jpl0937g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
mit0937g.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.

jpl0937g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0937g.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.

jpl0937g.snx: GALA    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0937g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
jpl0937g.snx: HOFN    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0937g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
ncl0937g.snx: MDVO    Antenna missing.                          .146   .000   .000
jpl0937g.snx: MOIN    .110   .000   .000   .128   .000   .000   .994   .000   .000
jpl0937g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0937g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0937g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000

FILE ncl0937g.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 ASC1 JPL-NCL   Lat BRAZ JPL-NCL   Lat FORT JPL-NCL
   Lat KERG MIT-JPL   Lon MATE MIT-JPL   Lon FORT MIT-JPL
   Lon OHIG MIT-NCL   Hgt MCM4 MIT-JPL   Hgt KERG MIT-JPL
   Hgt FORT MIT-JPL   Hgt YAR1 MIT-JPL   Hgt KERG MIT-NCL

59 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ AUCK BAHR BOR1 BRMU CAS1 CHAT
   COCO CRO1 DAV1 DGAR DRAO EISL FAIR GOLD HOB2 IISC
   IRKT KELY KIRU KIT3 KOKB KOSG KWJ1 MAC1 MADR MAS1
   MDO1 METS MKEA NLIB NRC1 NTUS ONSA PERT POL2 POTS
   RCM6 REYK SHAO STJO TAEJ TAHI THU1 TIDB TSKB USNO
   USUD VILL WES2 WHIT WSRT WTZR XIAN YELL ZWEN 

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

AVERAGE COORDINATE RMS USING ITRF94:

             59    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.2       1.2       1.6        7.5        7.1        7.0 
Lon        2.5       1.8       1.7        9.4        7.9        8.4 
Hgt        4.0       3.0       2.9       11.7       11.4       10.3 
3D         4.9       3.7       3.7       16.8       15.6       15.0

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

        59    GLOBAL  STATIONS          9   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.156     0.979     0.563      2.340      1.723      1.574

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      -6.7     4.9    14.8     5.8    19.4     6.4        -2.2      0.5
MIT      -4.4     3.0     7.7     3.7     7.3     3.5        -2.1      0.4
NCL      -6.8     4.4    19.4     5.0    25.7     6.5        -2.1      0.5

REMARKS:

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM mit0937g.snx :
   Stations: HART TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM jpl0937g.snx :
   Stations: TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM ncl0937g.snx :
   Stations: HART SANT TROM

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

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