Subject: [IGSREPORT-4678] Wk 0934 G-SINEX Comparisons
From: AC Coordinator / NRCan GSDivision
Date: Mon, 9 Mar 1998 9:08:33 PST

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IGS Electronic Report    Mon Mar  9  9:08:33 PST 1998      Message Number 4678
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Author: AC Coordinator / NRCan GSDivision
Subject: Wk 0934 G-SINEX Comparisons

Comparison of GNAAC Combined SINEX Solutions - Week 0934   
(NOV 30, 1997 - DEC 6, 1997)

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:
   mit0934g.snx at cddis.gsfc.nasa.gov
   jpl0934g.snx at cddis.gsfc.nasa.gov
   ncl0934g.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))

jpl0934g.snx: BISH    .075   .002  -.001   .069  -.001   .002   .046   .000   .000
mit0934g.snx: BISH    .078   .000  -.003   .074  -.003  -.001   .046   .000   .000
   - Unresolvable (no log file)

jpl0934g.snx: ELAT    .069   .000   .000   .068   .000   .000  -.011   .000   .000
mit0934g.snx: ELAT    .078   .000  -.003   .074  -.003  -.001  -.011   .000   .000
   - Unresolvable (no log file)

jpl0934g.snx: KATZ    .069   .000   .000   .068   .000   .000  -.012   .000   .000
mit0934g.snx: KATZ    .078   .000  -.003   .074  -.003  -.001  -.012   .000   .000
   - Unresolvable (no log file)

jpl0934g.snx: KOUR    .078   .000   .000   .096   .000   .000   .132   .000   .000
mit0934g.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.

jpl0934g.snx: TELA    .069   .000   .000   .068   .000   .000   .000   .000   .000
mit0934g.snx: TELA    .078   .000  -.003   .074  -.003  -.001   .000   .000   .000
   - Unresolvable (no log file)

jpl0934g.snx: WUHN    .110   .000   .000   .128   .000   .000  2.320   .000   .000
mit0934g.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.

jpl0934g.snx: YAR1    .078   .000   .000   .096   .000   .000   .073   .000   .000
mit0934g.snx: YAR1    .110   .000   .000   .128   .000   .000   .081   .000   .000
   - Both wrong. Should be L1/L2 offset .110, .128 M., eccentricity 0.081 M.

jpl0934g.snx: HARK    .110   .000   .000   .128   .000   .000  9.754   .000   .000
jpl0934g.snx: HOFN    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0934g.snx: LPGS    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0934g.snx: MALI    .078   .000   .000   .096   .000   .000   .222   .000   .000
jpl0934g.snx: MOIN    .110   .000   .000   .128   .000   .000   .994   .000   .000
jpl0934g.snx: NICO    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0934g.snx: SELE    .110   .000   .000   .128   .000   .000   .000   .000   .000
jpl0934g.snx: ZIMM    .069   .000   .000   .068   .000   .000   .000   .000   .000

FILE ncl0934g.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 OHIG JPL-NCL   Lat OHIG MIT-JPL   Lat KERG MIT-JPL
   Lat KERG MIT-NCL   Lat CAS1 MIT-NCL   Lon KWJ1 MIT-NCL
   Hgt BRAZ MIT-JPL   Hgt MCM4 MIT-NCL   Hgt BRAZ MIT-NCL

61 GLOBAL STATIONS:
   ALBH ALGO ANKR AREQ ASC1 AUCK BAHR BOR1 BRMU CHAT
   COCO CRO1 DGAR DRAO EISL FAIR FORT GOLD GUAM HOB2
   IISC IRKT KELY KIRU KIT3 KOKB KOSG KSTU MAC1 MADR
   MAS1 MATE MDO1 METS MKEA NLIB NTUS ONSA PERT POL2
   POTS RCM6 REYK SANT SHAO STJO TAEJ 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:

             61    GLOBAL  STATIONS         11   FIDUCIAL   STATIONS
        MIT-JPL   MIT-NCL   JPL-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
           (mm)      (mm)      (mm)       (mm)       (mm)       (mm)
        -------   -------   ------- ---------- ---------- ----------
Lat        1.3       1.5       1.4        7.5        7.5        7.5 
Lon        2.1       3.7       2.9       11.9       10.3        9.8 
Hgt        3.4       4.2       2.9       11.0       11.5       11.5 
3D         4.2       5.8       4.3       17.9       17.2       16.9

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

        61    GLOBAL  STATIONS         11   FIDUCIAL   STATIONS
   JPL-NCL   MIT-JPL   MIT-NCL MIT-ITRF94 JPL-ITRF94 NCL-ITRF94
   -------   -------   ------- ---------- ---------- ----------
     0.223     1.237     0.833      2.492      1.650      1.702

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       0.5     4.3     0.7     4.4    21.4     6.3        -1.4      0.4
MIT       3.1     2.6    -3.8     2.7    13.0     3.2        -1.1      0.3
NCL       4.4     4.6    10.7     4.7    13.1     8.9        -1.6      0.4

REMARKS:

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM mit0934g.snx :
   Stations: HART TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM jpl0934g.snx :
   Stations: TROM

THE FOLLOWING ITRF94 FIDUCIAL STATIONS ARE MISSING FROM ncl0934g.snx :
   Stations: HART TROM

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

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