Subject: [IGSREPORT-4582] Wk 0940 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Thu, 5 Feb 1998 13:39:10 PST

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IGS Electronic Report    Thu Feb  5 13:39:10 PST 1998      Message Number 4582
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0940 G-SINEX Comparisons

Subject: Wk 0940 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0940   
(JAN 11, 1998 - JAN 17, 1998)

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:
   mit0940g.snx at cddis.gsfc.nasa.gov
   jpl0940g.snx at cddis.gsfc.nasa.gov
   ncl0940g.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))

jpl0940g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0940g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
   - Unresolvable (no log file)

jpl0940g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0940g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
   - Unresolvable (no log file)

jpl0940g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0940g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
   - Unresolvable (no log file)

jpl0940g.snx: KOUR    .078   .000   .000   .096   .000   .000   .132   .000   .000
mit0940g.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.

jpl0940g.snx: MALI    .078   .000   .000   .096   .000   .000   .222   .000   .000
mit0940g.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.

jpl0940g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0940g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
   - Unresolvable (no log file)

jpl0940g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
mit0940g.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.

jpl0940g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0940g.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.

jpl0940g.snx: GALA    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0940g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
jpl0940g.snx: HOFN    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0940g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
ncl0940g.snx: MDVO    Antenna missing                           .146   .000   .000
jpl0940g.snx: MOIN    .110   .000   .000   .128   .000   .000   .994   .000   .000
jpl0940g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0940g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0940g.snx: UPAD    .078   .000  -.003   .074  -.003  -.001  1.962   .000   .000
jpl0940g.snx: ZECK    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0940g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000

FILE ncl0940g.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 EISL MIT-JPL   Lat OHIG MIT-JPL
   Lat DAV1 MIT-JPL   Lat KERG MIT-NCL   Lat DAV1 MIT-NCL
   Lat CAS1 MIT-NCL   Lon NTUS MIT-JPL   Lon KERG MIT-JPL
   Lon CAS1 MIT-JPL   Lon COCO MIT-JPL   Lon DGAR MIT-NCL
   Hgt IRKT JPL-NCL   Hgt USUD MIT-JPL   Hgt TAHI MIT-JPL
   Hgt MCM4 MIT-JPL   Hgt USUD MIT-NCL   Hgt ASC1 MIT-NCL
   Hgt TAHI MIT-NCL   Hgt IRKT MIT-NCL     

55 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ AUCK BAHR BOR1 BRMU BRUS CHAT
   CRO1 DRAO FAIR FORT GOLD GUAM HOB2 KELY KIRU KIT3
   KOKB KOSG KWJ1 MAC1 MADR MAS1 MATE MDO1 METS MKEA
   NLIB NRC1 ONSA PERT POL2 POTS RCM6 REYK SANT SHAO
   STJO TAEJ THU1 TIDB TSKB USNO VILL WES2 WHIT WSRT
   WTZR XIAN YAR1 YELL ZWEN     

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

AVERAGE COORDINATE RMS USING ITRF94:

             55    GLOBAL  STATIONS         11   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.1       1.1       0.7        8.7        8.7        8.4 
Lon        1.6       2.2       1.7       10.5        9.7        9.2 
Hgt        2.7       2.7       1.9       10.7       11.1       10.5 
3D         3.4       3.7       2.6       17.3       17.2       16.3

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

        55    GLOBAL  STATIONS         11   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.135     0.689     0.333      2.560      1.950      1.988

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      -8.5     4.2    32.3     4.2    28.6     6.0        -1.9      0.4
MIT      -6.9     2.8    10.4     2.9    25.9     3.5        -1.8      0.3
NCL      -8.7     4.3    29.5     4.4    22.5     6.3        -1.7      0.4

REMARKS:

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM mit0940g.snx :
   Stations: HART TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM jpl0940g.snx :
   Stations: TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM ncl0940g.snx :
   Stations: HART TROM

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

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