Subject: [IGSREPORT-4569] Wk 0936 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Tue, 3 Feb 1998 11:02:00 PST

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IGS Electronic Report    Tue Feb  3 11:02:00 PST 1998      Message Number 4569
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0936 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0936   
(DEC 14, 1997 - DEC 20, 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:
   mit0936g.snx at cddis.gsfc.nasa.gov
   jpl0936g.snx at cddis.gsfc.nasa.gov
   ncl0936g.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))

jpl0936g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0936g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
   - Unresolvable (no log file)

jpl0936g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0936g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
   - Unresolvable (no log file)

jpl0936g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0936g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
   - Unresolvable (no log file)

jpl0936g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0936g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
   - Unresolvable (no log file)

jpl0936g.snx: KOUR    .078   .000   .000   .096   .000   .000   .132   .000   .000
mit0936g.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.

jpl0936g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
mit0936g.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.

jpl0936g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0936g.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.

jpl0936g.snx: GALA    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0936g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
jpl0936g.snx: HOFN    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0936g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
ncl0936g.snx: MDVO    Antenna missing.                          .146   .000   .000
jpl0936g.snx: MOIN    .110   .000   .000   .128   .000   .000   .994   .000   .000
jpl0936g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0936g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0936g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000

FILE ncl0936g.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 KERG MIT-NCL   Lon METS MIT-JPL
   Lon BAHR MIT-JPL   Lon OHIG MIT-NCL   Hgt YAR1 JPL-NCL
   Hgt MCM4 MIT-JPL   Hgt YAR1 MIT-JPL     

63 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ ASC1 AUCK BOR1 BRAZ BRMU BRUS
   CAS1 CHAT COCO CRO1 DGAR DRAO EISL FAIR FORT GOLD
   GUAM HOB2 IISC IRKT KELY KIRU KIT3 KOKB KOSG KWJ1
   MAC1 MADR MAS1 MATE MDO1 MKEA NLIB NRC1 NTUS ONSA
   PERT POL2 POTS RCM6 REYK SANT SHAO STJO TAEJ TAHI
   THU1 TIDB TSKB USNO USUD VILL WES2 WHIT WSRT WTZR
   XIAN YELL ZWEN       

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

AVERAGE COORDINATE RMS USING ITRF94:

             63    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.9       1.3       1.9        6.9        7.2        7.2 
Lon        2.5       1.6       1.9        8.0        7.0        7.3 
Hgt        4.9       3.3       3.5        9.8       11.0        9.2 
3D         5.8       3.9       4.4       14.4       14.9       13.8

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

        63    GLOBAL  STATIONS         10   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.146     1.368     0.575      1.778      1.450      1.374

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      -7.1     4.1     8.3     4.4     3.6     6.1        -1.9      0.4
MIT      -4.4     2.8     3.3     3.1    -5.7     3.3        -1.9      0.4
NCL      -6.8     4.2    12.4     4.4    11.5     6.1        -1.8      0.4

REMARKS:

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM mit0936g.snx :
   Stations: HART TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM jpl0936g.snx :
   Stations: TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM ncl0936g.snx :
   Stations: HART TROM

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

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