Subject: [IGSMAIL-62] JPL analysis results
From: James F. Zumberge
Date: 7 AUG 1992 09:37:50

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IGS Electronic Mail        7-AUG-1992 09:37:50       Message Number 62
***********************************************************************
 
==============================================================================
                   THIS FILE CONTAINS 5 MESSAGES
==============================================================================

From:    James F. Zumberge
Subject: JPL analysis results
         --------------------

Submitted by

G Blewitt, J F Zumberge, M B Heflin, D C Jefferson, F H Webb

all at the Jet Propulsion Laboratory, California Institute of Technology, 
Pasadena, CA  91109.

The following files have been posted on BODHI (for access to BODHI contact
[email-masked]) and will be available soon from the CDDIS:
______________________________________________________________________________
filename               contents
______________________________________________________________________________
jpl06547.sum           this text file
jpl06535.erp           polar motion results for day 1992 Jul 17
jpl06536.erp           polar motion results for day 1992 Jul 18
jpl0653x.erp           polar motion results for days 1992 Jul 17-18
                          with new fiducial network (see below)
jpl06547.erp           polar motion results for week 1992 Jul 19-25
jpl06535.sp1           precise ephemerides for 1992 Jul 17, sp1 format
jpl06535.sp3                               "                    sp3
jpl06536.sp1           precise ephemerides for 1992 Jul 18, sp1 format
jpl06536.sp3                               "                    sp3
jpl06547.sp1           precise ephemerides for week 1992 Jul 19-25, sp1 format
jpl06547.sp3                               "                        sp3
______________________________________________________________________________

Files jpl0653*, contain the results missing from last week's submission because
of late-appearing data from the DSN. (See special note below regarding file
jpl0653x.erp.)

Starting with this submission, we have changed our fiducial strategy.
Whereas before, we constrained the positions (with 0.1 mm a priori sigmas) of
ALGO, FAIR and MADR using our realization of ITRF90, we now constrain 
ALGO, FAIR, MADR, HART, KOKB, SANT, TROM, YAR1 using ITRF91 coordinates.
With the following 2 exceptions, we use the coordinates, site ties, and 
antenna height given by Z. Altamimi and C. Boucher in IGS Mail Message #33:
      STATION		Comment
      -------           -------
      HART		Used coordinates for 7232 plus site tie 
      			dx = -817.317 m instead of the quoted dx = -817.371 m.
                        (We are still not quite sure which of these is correct).
                        Note that quoted coordinates for "HART" in message #33
      			implicitly assumed an incorrect antenna height.
      SANT              Used coordinates as quoted in IGS mail #33 for 
                        "SANT" plus the following tie from SANT to SANTIAGO
                        GPS #4001 1992 (the current monument upon which the GPS
                        antenna is mounted): 
                                 dx = -31.374 m, dy = -61.808 m, dz = 75.245 m
                        The ground survey adjustment was performed by
                        Bendix/GSFC (see also, IGS mail #42). We do not
                        recommend using the SLR-based position for monument
                        7400 since it is in ~25 cm disagreement with both GPS
                        and VLBI solutions.

For completeness, here are the fiducial coordinates we previously assumed, 
and the fiducial coordinates we now assume.  Please pay careful attention to
the fact that our convention is to use the top of the choke ring as the
ARP (antenna reference point).  This is because this convention allows us,
in the absence of other knowledge, to assume a phase center offset of 
Dorne-Margolin antenna which is independent of choke ring height (the new 
TurboRogue stations will have a different choke ring thickness).  We are
aware of the fact that other analysis centers use the bottom of the choke
ring as the ARP, in which case the numbers quoted below must be corrected for 
the choke ring thickness (7 cm).

PREVIOUS FIDUCIAL COORDINATES (ITRF90 GPS solution):
-----------------------------
      						  Height to
 Site        X(m)          Y(m)          Z(m)    Top of Ring(m)
 ---------------------------------------------------------
 ALGO  	  918129.5841 -4346071.2094  4561977.7947   0.184
 FAIR	-2281621.3243 -1453595.7491  5756961.9449   0.186
 MADR	 4849202.5864  -360329.2017  4114913.0940   0.000
 ---------------------------------------------------------

CURRENT FIDUCIAL COORDINATES (ITRF91, based on IGS Message #33):
----------------------------
      						  Height to
 Site        X(m)          Y(m)          Z(m)    Top of Ring(m)
 ---------------------------------------------------------
 ALGO  	  918129.616  -4346071.224   4561977.800    0.184
 FAIR	-2281621.327  -1453595.775   5756961.976    0.186
 MADR	 4849202.559   -360329.183   4114913.048    0.000
 HART    5084625.458   2670366.499  -2768494.039    9.824
 KOKB   -5543838.080  -2054587.522   2387809.570    0.163
 SANT    1769693.275  -5044574.126  -3468321.172    0.163
 TROM    2102940.451    721569.379   5958192.072    2.543
 YAR1   -2389025.331   5043316.830  -3078530.926    0.143
 ---------------------------------------------------------

As before, the assumed phase center offsets from the TOP of the choke ring 
for ROGUE Dorne-Margolin antennas are:

Band         East [m]    North [m]     Up [m]
---------------------------------------------
L1            0.0000       0.0000      0.0079	
L2            0.0000       0.0000      0.0264	
LC            0.0000       0.0000     -0.0207
---------------------------------------------
            
A check on baselines up to 1700 km show no discernable step-function
in estimated baseline coordinates at the time we started using this new
strategy, so we are confident that this change will not be detrimental to 
regional network users. We do, however see a step-function in our polar
motion series at the 1- to 2-milliarcsecond level.  For this reason, we quote 
polar motion solutions for 2 days in common for both the ITRF90 3-fiducial
strategy, and the ITRF91 8-fiducial strategy.

Thus file jpl0653x.erp contains polar motion results for days 1992 Jul 17-18
with the new ITRF91 8-fiducial strategy, and can be compared with jpl06535.erp
and jpl06536.erp.

The change in strategy causes a ~30-cm 3d rms difference in orbits (determined
by analyzing Jul 17 and Jul 18 with both strategies.)

We have excluded prn12 from the analysis this week because of erratic behaviour.
Also, data from Onsala on Jul 22 and 23 have not been used.

Finally, although tracking data and broadcast epehemeris data have been
received from the newest GPS satellite (prn 26), we have found it best not to
include it yet.

WARNING: For GPS week 654, prn 12 behaved erratically.
WARNING: Data from Onsala are bad on July 22 and 23.
WARNING: We recommend against using prn 26 (yet).

JPL UTPM TABLE 1 (ITRF90 3-fiducial strategy)             (1992 Jul 17 - Jul 18)
  MJD       X        Y       UT1R-UTC XSIG    YSIG   UTSIG  RMS  XYC  XUC  YUC STA SAT PASS    
           ''        ''        sec     ''     ''      sec
 48820.5  -.12131   .41754   .00000  .00025  .00029  .00000  .0  .23  .00  .00  24 17  0
 48821.5  -.11923   .41880   .00000  .00030  .00035  .00000  .0  .09  .00  .00  25 17  0
END UTPM TABLE 1

JPL UTPM TABLE 2 (ITRF91 8-fiducial strategy)             (1992 Jul 17 - Jul 25)
  MJD       X        Y       UT1R-UTC XSIG    YSIG   UTSIG  RMS  XYC  XUC  YUC STA SAT PASS    
           ''        ''        sec     ''     ''      sec
 48820.5  -.12087   .41565   .00000  .00013  .00012  .00000  .0 -.22  .00  .00  24 17  0
 48821.5  -.11790   .41740   .00000  .00015  .00012  .00000  .0 -.24  .00  .00  25 17  0
 48822.5  -.11567   .42023   .00000  .00014  .00012  .00000  .0 -.17  .00  .00  26 16  0
 48823.5  -.11265   .42316   .00000  .00010  .00010  .00000  .0  .01  .00  .00  28 16  0
 48824.5  -.11002   .42543   .00000  .00011  .00013  .00000  .0 -.03  .00  .00  26 16  0
 48825.5  -.10822   .42738   .00000  .00010  .00012  .00000  .0 -.03  .00  .00  26 16  0
 48826.5  -.10640   .42902   .00000  .00011  .00013  .00000  .0 -.10  .00  .00  26 16  0
 48827.5  -.10425   .43124   .00000  .00010  .00011  .00000  .0 -.05  .00  .00  27 16  0
 48828.5  -.10185   .43336   .00000  .00010  .00011  .00000  .0  .01  .00  .00  26 16  0
END UTPM TABLE 2

The following table indicates the "orbit repeatability", as defined in IGS Mail
Message 37, for GPS week 653 (to complete last week's results):

JPL ORBIT REPEATABILITY TABLE 1              GPS week 653 (1992 Jul 12 - Jul 18)
      92  7 12   92  7 13   92  7 14   92  7 15   92  7 16   92  7 17   92  7 18
prn    rms (m)
  2       0.52       1.12       0.69       1.03       0.90       1.05       1.29
  3       0.37       0.53       0.34       0.40       0.45       0.34       0.48
 11       0.38       0.48       0.52       0.60       0.40       0.60       0.75
 12       0.46       0.88       1.17       0.54       0.57       0.48       0.63
 13       0.92       0.63       0.77       0.69       0.43       0.55       0.57
 14       1.10       1.23       1.38       0.91       1.52       1.08       1.01
 15       0.95       0.70       0.89       0.67       0.77       0.73       0.97
 16       0.35       0.45       0.64       0.48       0.34       0.57       0.52
 17       0.66       0.87       0.84       0.77       0.81       1.09       0.99
 18       0.40       0.55       0.40       0.31       0.29       0.49       0.41
 19       0.65       0.57       0.56       0.46       0.42       0.37       0.53
 20       0.62       0.73       0.57       0.63       0.42       0.64       0.98
 21       0.36       0.45       0.37       0.46       0.53       0.48       0.83
 23       0.41       0.53       0.27       0.27       0.54       0.56       0.76
 24       0.98       0.9                   0.5        0.50       0.72       0.85
 25       0.88       1.11       0.4                   0.6        0.72       0.52
 28       1.36       1.17       1.38       1.08       1.21       1.27       1.22
END ORBIT REPEATABILITY TABLE 1

For GPS week 654 the results are:

JPL ORBIT REPEATABILITY TABLE 2              GPS week 654 (1992 Jul 19 - Jul 25)
      92  7 19   92  7 20   92  7 21   92  7 22   92  7 23   92  7 24   92  7 25
prn    rms (m)
  2       1.30       1.00       1.75       2.00       1.21       1.67       0.75
  3       0.43       0.62       0.63       0.72       0.74       0.97       0.62
 11       0.49       0.28       0.54       0.56       0.46       0.77       0.76
 13       0.35       0.83       0.61       0.95       0.77       0.47       0.66
 14       0.52       0.52       0.77       0.85       0.90       1.48       0.89
 15       1.11       1.44       1.96       1.71       1.47       1.65       1.68
 16       0.38       0.42       0.76       0.46       0.49       0.49       0.76
 17       1.00       1.23       0.95       1.15       0.93       0.91       1.38
 18       0.58       0.56       0.38       0.64       0.61       0.41       0.77
 19       0.99       1.16       0.65       0.75       0.82       0.66       0.52
 20       1.05       0.93       1.18       1.24       1.29       1.16       0.94
 21       0.58       0.60       0.97       0.95       0.87       0.64       0.86
 23       0.62       0.71       0.78       0.53       0.57       0.97       0.77
 24       0.76       1.12       0.76       0.60       0.80       1.01       0.92
 25       0.93       1.02       0.71       0.61       1.02       0.77       0.84
 28       1.21       0.79       1.12       1.16       1.04       0.78       0.70
END ORBIT REPEATABILITY TABLE 2

As described in IGS Mail Message 37, the following tables compares the JPL
precise ephemerides with those from the broadcast ephemeris (included are 
results from GPS week 653 and 654):

JPL COMPARISON OF BROADCAST NAVIGATION MESSAGE WITH PRECISE EPHEMERIDES 1
      92  7 12   92  7 13   92  7 14   92  7 15   92  7 16   92  7 17   92  7 18
prn    rms (m)
  2       6.3        5.6        6.0        6.4        6.3        5.4        5.3 
  3      11.2       12.6       13.2       12.8       11.3       11.8       13.0 
 11       5.7        9.0        5.4        6.5        5.1        7.8        6.3 
 12      12.7        8.0       17.0       13.5       11.6        9.2       12.8 
 13       5.5        6.1        8.7        7.3        7.9        8.8        7.5 
 14       5.7        5.9        6.1        6.2        6.4        6.1        6.4 
 15       6.9        8.9        9.2        8.2        7.4        6.2        8.1 
 16       8.1        7.4        9.9       10.0       11.8        9.8        8.5 
 17       7.2        7.0        7.9        8.4        7.7        5.5        7.2 
 18       7.4        7.2        7.4        7.5        8.1        8.5        7.7 
 19       8.1        7.3        7.9        8.2        6.6        5.9        6.8 
 20       4.5        3.7        4.6        4.2        5.0        4.9        5.5 
 21       6.1        5.9        5.1        5.1        5.7        6.2        7.7 
 23       5.9        4.9       10.2        7.2        4.4        4.0       11.8 
 24      15.1       13.4                  13.5       12.6       13.3       13.9 
 25       9.1        9.8       10.5                  17.5       10.3       13.5 
 28       5.3        4.3        4.2        5.0        4.1        4.1        4.4 
END COMPARISON OF BROADCAST NAVIGATION MESSAGE WITH PRECISE EPHEMERIDES 1

JPL COMPARISON OF BROADCAST NAVIGATION MESSAGE WITH PRECISE EPHEMERIDES 2
      92  7 19   92  7 20   92  7 21   92  7 22   92  7 23   92  7 24   92  7 25
prn    rms (m)
  2       5.8        6.3        5.8        5.9        6.8        6.7        5.8 
  3      11.8       11.9       10.7       11.0       11.9       11.2       10.6 
 11       8.3       12.9        4.7        4.9        6.0        7.6       10.9 
 13       6.7        6.2        6.5        7.7        5.7        5.8        6.5 
 14       8.0        6.5        7.2        7.9        6.7        7.0        6.2 
 15       9.4        5.7        5.2        6.9        8.7        8.1        7.5 
 16      10.3        9.6        8.9        8.5        7.2        6.5        7.9 
 17       6.3        5.6        8.0        8.3        8.8        8.3        7.4 
 18       7.7        6.5        6.5        6.0        5.6        7.4        6.7 
 19       8.0        7.5        7.2        6.9        4.7        5.5        6.6 
 20       4.4        5.0        4.5        4.9        6.6        5.8        5.1 
 21       6.7        5.5        7.1        6.0        6.2        5.9        8.2 
 23       7.0        6.2        8.4        5.8        9.7        5.4        4.8 
 24      13.7       11.1       12.0       15.6       13.2       14.1       15.0 
 25      17.1        7.5        4.8        6.6        6.1        7.4        7.4 
 28       6.6        4.3        4.3        4.6        4.9        4.4        4.9 
END COMPARISON OF BROADCAST NAVIGATION MESSAGE WITH PRECISE EPHEMERIDES 2

==============================================================================

From:     Joachim Feltens
Subject:  ESA/ESOC analysis results
          -------------------------

-------------------------
ANALYSIS CENTRE: ESA/ESOC
-------------------------

OUTLINE OF THE ESTIMATION OF GPS-ORBITS AND EARTH ROTATION PARAMETERS AT THE
ESOC PROCESSING CENTER FOR IGS

J.M.Dow, S.Casotto, J.Feltens, S.Frey, C.Garcia-Martinez, T.Martin-Mur

Description of analysis for period 1992 July 19 - 25 (days 201-207,GPS week 654)

1. SOFTWARE USED:   GPSOBS/BAHN5

2. MODELS AND CONSTANTS USED

   a) General:                 no changes with respect to previous runs

   b) Satellite Force Model:   no changes with respect to previous runs

      The following table gives an overview over the satellites that have been
      used for the different one-day-arc solutions:     "+" used, "-" not used.
      __________________________________________________________________________
      PRN02| 03| 11| 12| 13| 14| 15| 16| 17| 18| 19| 20| 21| 23| 24| 25| 26| 28|
      ____-|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
      DAY| |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
      201|+| + | + | + | + | + | + | + | + | + | + | + | + | + | + | + |   | + |
      202|+| + | + | + | + | + | + | + | + | + | + | + | + | + | + | + |   | + |
      203|+| + | + | + | + | + | + | + | + | + | + | + | + | + | + | + |   | + |
      204|+| + | + | + | + | + | + | + | + | + | + | + | + | + | + | + |   | + |
      205|+| + | + | + | + | + | + | + | + | + | + | + | - | + | + | + | - | + |
      206|-| + | + | + | + | + | + | + | + | + | + | + | + | + | + | + | + | + |
      207|+| + | + | + | + | + | + | + | + | + | + | + | + | + | + | + | + | + |

   c) Ground Stations (if being estimated, one position (X,Y,Z) every day):

      The following table gives an overview over the ground stations,  that have
      been included into the GPS-data processing at ESOC. Except where otherwise
      noted ("remarks"), corrections are taken from IGS Mail No. 33  -  IGS site
      information and coordinates  -  (Boucher and Altamimi).
      __________________________________________________________________________
                          |             |    |    GPS WEEK 654     |
                          |             |    | 2  2  2  2  2  2  2 |
                          |             |    | 0  0  0  0  0  0  0 |
              SITE        |   COUNTRY   |CODE| 1  2  3  4  5  6  7 |  REMARKS
      --------------------|-------------|----|---------------------|------------
        Algonquin         | Canada      |ALGO| F  F  F  F  F  F  F |
        CANB/Tidbinbilla  | Australia   |TIDB| -- E ------ E  E  E | Bern
        Penticton         | U.S.A.      |DRAO| E  E  E  E  E  E  E |
        Fairbanks         | U.S.A/Alaska|FAIR| F  F  F  F  F  F  F |
        Goldstone         | U.S.A.      |GOLD| E  E  E  E  E  E  E |
        Herstmonceux      | U.K.        |HERS| E  F  E  E  F  F  F |
        Kokee Park        | U.S.A/Hawaii|KOKB| E  E  E  E  E  E  E |
        Kourou      (ESA) | French Guyan|KOUR| ------------------- |
        Madrid            | Spain       |MADR| F  F  F  F  F  F  F |
        Maspalomas  (ESA) | Spain/Can.Is|MASP| E  E  E  E  E  E  E |
        Matera            | Italy       |MATE| -- E  E  E  E  E  E |
        McMurdo           | Antarctica  |MCMU| E  E  E  E  E  E  E | IGS Mail 44
        Metsahovi         | Finland     |METS| E ----------------- |
        Ny Alesund/Spitzb.| Norway      |NYAL| -- E  E  E  E  E  E |
        Onsala            | Norway      |ONSA| E ----------------- |
        Pamate/Tahiti     | France      |PAMA| E  E  E  E  E  E  E | IGS Mail 44
        Tai-Shi           | Taiwan      |TAIW| E  E  E  E  E  E  E | Bern
        Usuda             | Japan       |USUD| -- E  E  E -------- |
        Wettzell          | Germany     |WETB| E  E  E  E  E  E  E |
        Yaragadee         | Australia   |YAR1| F  F  F  F  F  F  F |
        Yellowknife       | Canada      |YELL| F  F  F  F  F  F  F |

      with: "F" ... coordinates of ground station kept fixed,
            "E" ... coordinates of ground station estimated,
            "-" ... ground station not included on that day.

   d) Earth Rotation Parameters:   no changes with respect to previous runs

   e) Observations:                no changes with respect to previous runs

3. PARAMETERS TO BE ESTIMATED PER 1-DAY ARC

   a) Satellite Parameters per Spacecraft:    no changes with respect to
                                                                   previous runs
   b) Station related parameters per ground station:  no changes with respect to
                                                                   previous runs
   c) Earth Rotation Parameters:              no changes with respect to
                                                                   previous runs
4. PARAMETERS TO BE KEPT FIXED IN THE SOLUTION

   a) Satellite Parameters per Spacecraft:    no changes with respect to
                                                                   previous runs
   b) Station related parameters per Ground Station:  no changes with respect to
                                                                   previous runs
5. PRODUCTS GENERATED

   The following products are generated and stored in CDDIS at NASA/GSFC:

   ESA06540.EPH   - Precise GPS orbits for day 201 (July 19)
   ESA06541.EPH   - Precise GPS orbits for day 202 (July 20)
   ESA06542.EPH   - Precise GPS orbits for day 203 (July 21)
   ESA06543.EPH   - Precise GPS orbits for day 204 (July 22)
   ESA06544.EPH   - Precise GPS orbits for day 205 (July 23)
   ESA06545.EPH   - Precise GPS orbits for day 206 (July 24)
   ESA06546.EPH   - Precise GPS orbits for day 207 (July 25)
   ESA06547.ERP   - Earth rotation results for week beginning 1992 July 19
   ESA06547.SUM   - The name of this text file

==============================================================================

From:    Dave Starr
Subject: data rate
         ---------

Please be advised that the data rate for GOLD was at 120 seconds from
approximately 4 Aug 1992 18:25 to 6 Aug 1992 16:00 UT.
Dave Starr
JPL GPS Network Operations

==============================================================================

From:    Bob E. Schutz
Subject: CSR/UTX analysis results (week 650)
         -----------------------------------

                   IGS ANALYSIS CENTER REPORT
     CENTER FOR SPACE RESEARCH/UNIVERSITY OF TEXAS AT AUSTIN

Report Period:  1992 June 21-June27
                (Days 173-179, GPS Week 650)

Report Date:  1992 August 3 (Note: this is a revised submission)

This report provides additional information about GPS products generated
by the Center for Space Research/University of Texas at Austin (UTX) for
the International GPS Geodynamics Service (IGS). 

PRODUCTS SUMMARIZED

GPS ephemerides and Earth rotation parameters were generated for the
reporting period.  The Earth rotation parameters do not currently include
UT1.  The results may be obtained from the NASA CDDIS.  The currently
available files are:

   UTX06507.EPH:  GPS ephemerides for GPS Week 650 (revised)
                     (SP3 format, position only) 
   UTX06507.SUM:  This report file
   UTX06507.ERP:  Earth rotation summary file

This revised ephemeris file corrects a time tag problem of the original
submission and introduces a new strategy in the ephemeris computation to
be used with future submissions.

CORE STATION SUMMARY

The Core Station data used in the solutions are given below.  Missing data
on some days does not imply that no data are available.  X in the table 
indicates that data from that site were used in the solution.

                                            DATA USED IN SOLUTIONS
                                                 Days 173-179
                                                Day of Week 650
                                              S  M  T  W  T  F  S
                                              U  O  U  E  H  R  A
                                              N  N  E  D  U  I  T

        Site                         Code

Algonquin, Ontario      Canada       ALGO     X  X  X  X  X  X  X
Fairbanks, AK           USA          FAIR     X  X  X  X  X  X  X
Hartebeestoek           S. Africa    HART        X  X  X  X  X
Kokee Park, HI          USA          KOKB     X  X  X  X
Kootwijk                Netherlands  KOSG     X  X  X  X  X  X  X
Madrid (DS60)           Spain        MADR     X  X  X  X  X  X  X
Mas Palomas (ESOC)      Canary I.    MASP                    X  X
McMurdo                 Antarctica   MCMU     X  X  X  X  X  X  X
Ny Alesund              Norway       NYAL     X  X  X  X  X  X
Onsala                  Sweden       ONSA     X
Papeete                 Tahiti       PAMA        X  X  X  X  X
Pinyon (PGGA), CA       USA          PIN1     X  X  X  X  X  X  X
Santiago                Chile        SANT     X  X  X  X  X  X  X
Tai-shi                 Taiwan       TAIS     X  X  X  X  X  X  X
Tidbinbilla (DS40)      Australia    TIDB     X  X  X  X     X  X
Usuda                   Japan        USUD     X  X  X  X  X  X  X
Wettzell                Germany      WETT     X  X  X  X  X  X  X
Yaragadee               Australia    YAR1     X  X  X  X  X  X  X
Yellowknife             Canada       YELL     X     X  X  X  X  X

                               Totals        16 16 17 17 15 17 14

SATELLITE SUMMARY

  PRN        PERCENT TIME                   COMMENTS
               IN SHADOW

    2             0.0                    Nominal
    3             2.4                    Nominal
   11             2.3                    Nominal
   12             3.2                    Nominal
   13             1.8                    Nominal
   14             0.0                    Nominal
   15             0.0                    Nominal
   16             0.0                    Nominal
   17             0.0                    Nominal
   18             0.0                    Nominal
   19             7.2                    Nominal
   20             0.0                    Nominal
   21             0.0                    Nominal
   23             0.0                    Nominal
   24             0.0                    Nominal
   25             7.2                    Nominal
   28             0.0                    Nominal

SOLUTION CHARACTERISTICS

Force Model:  IERS Standards
Reference Frame:  Defined by fixed stations in SLR (CSR91L03) and
                  VLBI (GLB718)
Software:  MSODP1/TEXGAP
Data:  L1/L2 GPS phase sampled at 2 min., processed as double differences
Minimum Elevation:  15 degrees
Arc Length:
   UTX06507.EPH:  Based on 7-day continuous arc, with overlap arc,
                     described below.
                
   UTX06507.ERP:   1-day arcs
Adjusted Parameters:
   6 epoch elements, nongravitational force parameters for each satellite
   Zenith delay parameter each 2.5 hr for each station
   Double difference bias parameters
   Pole position (in one-day arcs)

SOLUTION DETAILS:

   UTX06507.EPH (7-day arc):
     Passes:   1921
     Double differences (DD):  95293
     RMS of DD:  1.58 cm (based on the 7-day continuous arc)
     Comment:  This ephemeris is based on a continuous 7-day arc.  However,
               to provide a smooth transition between this week and the
               next week, a four-day arc spanning the last two days of the
               current week and the first two days of the next week is used.
               The transition is illustrated below:

                        Week 650    |        Week 651    |
         Day ->  0  1  2  3  4  5  6| 0  1  2  3  4  5  6|                   
               |--|--|--|--|--|--|--|--|--|--|--|--|--|--|
                              
                              |--|--|--|--| 4-day overlap arc

               The UTX0607.EPH ephemeris file for Week 650 contains days 0
               to 5 of the 7-day continuous arc plus the ephemeris taken from
               day 6 of the 4-day overlap arc.  For Week 651(and future 
               ephemerides), days 1 to 5 will come from the continuous 7-day
               arc, but day 0 and 6 will be taken from 4-day overlap arcs.
               For Week 650, a discontinuity exists at June 27 00:00
               with the values given below (DX,DY,DZ represent ephemeris
               differences in the Earth-fixed frame and DR,DT,DN represents
               the same differences expressed in a radial, transverse
               (along-track) and normal (cross-track) reference frame.
               This is the only discontinuity that exists in UTX06507.EPH.
               There is no discontinuity at the common point between Week 650
               and Week 651.

               Ephemeris Difference:  1992  6 27  0  0  0.0000000
                                  
           PRN   DX(m)     DY(m)     DZ(m)       DR(m)     DT(m)     DN(m)

            2   -0.1800    0.9000   -0.1100     -0.1066    0.7762   -0.4906
            3    0.0400   -0.4100    0.0000     -0.0404    0.1568   -0.3788
           11   -0.0100   -0.0800   -0.0200     -0.0279   -0.0401   -0.0671
           12    0.3000    0.1100   -0.3700     -0.0922    0.4728    0.0837
           13   -0.2000   -0.4000   -0.4000      0.0062    0.4254   -0.4231
           14   -0.2600   -0.0100    0.4600      0.0105   -0.4383    0.2951
           15    0.2400    0.1200    0.2800      0.0267   -0.3789    0.0784
           16    0.0000    0.0400    0.1700      0.0372    0.1664    0.0378
           17   -0.0200    0.2100   -0.1400     -0.0255   -0.1590    0.1954
           18    0.0200   -0.2400    0.0100      0.0135   -0.1757    0.1645
           19    0.0900   -0.0400   -0.6200      0.0232   -0.6273   -0.0090
           20    0.3400   -0.1800    0.1900     -0.0040   -0.0762    0.4222
           21    0.2000    0.1900   -0.1900      0.0978   -0.2280   -0.2250
           23    0.0000    0.1800   -0.1900      0.0856   -0.2473   -0.0039
           24    0.0900   -0.3200   -0.2400     -0.0046    0.0687   -0.4042
           25   -0.0600   -0.5000    0.0300     -0.0901    0.1231    0.4808
           28    0.5300    0.0000   -0.2600     -0.1613   -0.3887    0.4140

               
The one day arcs used for the Earth rotation solutions have the following
characteristics:

   UTX06507.ERP: 
                        Day->      0     1     2     3     4     5     6

     Passes:                     275   275   308   249   247   282   286
     Double differences (DD):  13758 13179 15621 11710 11545 14294 15144
     RMS of DD (cm):             2.1   2.1   1.7   1.9   1.4   1.7   1.4
       [Day 0=Sunday; Day 6=Saturday)

----------------------------
For further information:
   Prof. B. E. Schutz
   [email-masked]

or Dr. P. A. M Abusali
   [email-masked]

==============================================================================

From:    Bob E. Schutz
Subject: CSR/UTX analysis results (week 651)
         -----------------------------------

                   IGS ANALYSIS CENTER REPORT
     CENTER FOR SPACE RESEARCH/UNIVERSITY OF TEXAS AT AUSTIN

Report Period:  1992 June 28-July 4
                (Days 180-186, GPS Week 651)

Report Date:  1992 August 5

This report provides additional information about GPS products generated
by the Center for Space Research/University of Texas at Austin (UTX) for
the International GPS Geodynamics Service (IGS). 

PRODUCTS SUMMARIZED

GPS ephemerides and Earth rotation parameters were generated for the
reporting period.  The Earth rotation parameters do not currently include
UT1.  The results may be obtained from the NASA CDDIS.  The currently
available files are:

   UTX06517.EPH:  GPS ephemerides for GPS Week 651 (SP3 format)
   UTX06517.SUM:  This report file
   UTX06517.ERP:  Earth rotation summary file

CORE STATION SUMMARY

The Core Station data used in the solutions is given below.  Missing data
on some days does not imply that no data are available.  X in the table 
indicates that data from that site were used in the solution.

                                            DATA USED IN SOLUTIONS
                                                 Days 180-186
                                                Day of Week 651
                                              S  M  T  W  T  F  S
                                              U  O  U  E  H  R  A
                                              N  N  E  D  U  I  T

        Site                         Code

Algonquin, Ontario      Canada       ALGO     X  X  X  X  X  X  X
Fairbanks, AK           USA          FAIR     X  X  X  X  X  X  X
Hartebeestoek           S. Africa    HART     X  X  X  X  X  X  X
Kokee Park, HI          USA          KOKB        X  X  X  X  X  X
Kootwijk                Netherlands  KOSG     X  X  X  X  X  X  X
Madrid (DS60)           Spain        MADR     X  X        X  X  X
Mas Palomas (ESOC)      Canary I.    MASP     X  X  X  X  X  X  X
McMurdo                 Antarctica   MCMU     X  X  X  X  X  
Ny Alesund              Norway       NYAL     X  X  X  X  X  X  X
Onsala                  Sweden       ONSA     X  X  X  X  X  X  X
Papeete                 Tahiti       PAMA     X  X  X  X  X  X
Pinyon (PGGA), CA       USA          PINY     X  X  X  X  X  X  X
Santiago                Chile        SANT     X     X  X  X  X  X
St. Johns, Newfoundland Canada       STJO     X  X  X  X  X  X  X
Tai-shi                 Taiwan       TAIW     X  X  X  X  X  X  X
Tidbinbilla (DS40)      Australia    TIDB     X  X  X  X  X  X  X
Usuda                   Japan        USUD     X  X  X  X  X  X  X
Wettzell                Germany      WETT     X  X  X  X  X  X  X
Yaragadee               Australia    YAR1     X  X  X  X  X  X  X
Yellowknife             Canada       YELL     X  X  X  X  X  X  X

                               Totals        19 19 19 19 20 19 18

SATELLITE SUMMARY

  PRN        PERCENT TIME                   COMMENTS
               IN SHADOW

    2             0.0      Nominal              
    3             0.0      Nominal
   11             0.0      Nominal
   12             6.6      1-day arcs indicate prn12 problem on day186
                            but no significant evidence for this in 7-day arc
   13             0.0      Nominal
   14             0.0      Nominal
   15             0.0      Nominal
   16             0.0      Nominal
   17             0.0      Nominal
   18             0.0      Nominal
   19             5.5      Nominal
   20             0.0      Nominal
   21             0.0      Nominal
   23             0.0      Nominal
   24             0.0      Nominal
   25             5.7      Nominal
   28             0.0      Nominal

SOLUTION CHARACTERISTICS

Force Model:  IERS Standards
Reference Frame:  Defined by fixed stations in SLR (CSR91L03) and
                  VLBI (GLB718)
Software:  MSODP1/TEXGAP
Data:  L1/L2 GPS phase sampled at 2 min., processed as double differences
Minimum Elevation:  15 degrees
Arc Length:
   UTX06517.EPH:   7-day continuous arc
   UTX06517.ERP:   1-day arcs
Adjusted Parameters:
   6 epoch elements, nongravitational force parameters for each satellite
   Zenith delay parameter each 2.5 hr for each station
   Double difference bias parameters
   Pole position (in one-day arcs)
Solution Statistics:

   UTX06517.EPH (7-day arc):
     Passes:   2641
     Double differences (DD): 131744
     RMS of DD: 1.82 cm
     Comment:   This ephemeris is based on a continuous 7-day arc.  As
                described in the report for Week 650, the first day and
                the last day of the continuous 7-day arc were removed and
                replaced by the corresponding days from 4-day arcs that
                spanned Weeks 650/651 and Weeks 651/652, respectively.
                Discontinuities are introduced with this strategy at
                June 29 00:00 and July 4 00:00.  The discontinuity values
                are give in the tables below.

              Ephemeris Difference:   1992  6 29  0  0  0.0000000

           PRN   DX(m)     DY(m)     DZ(m)       DR(m)     DT(m)     DN(m)

            2    0.3800   -0.0300    0.1800      0.0799    0.1375    0.3904
            3   -0.0600    0.1400   -0.0900     -0.0242   -0.1497    0.0911
           11    0.3100    0.2600   -0.1200      0.1734   -0.1542    0.3525
           12   -0.1600   -0.0300   -0.1500      0.1958    0.0475   -0.0917
           13   -0.0600    0.1700   -0.0500     -0.1553    0.0267    0.1009
           14   -0.2900    0.0600    0.0900     -0.0664   -0.0702    0.2941
           15    0.2800    0.0200    0.1100      0.0804   -0.2831   -0.0655
           16   -0.1000   -0.0400   -0.1600     -0.0480   -0.1783    0.0558
           17   -0.0600    0.4600   -0.2000     -0.0587   -0.2386    0.4414
           18   -0.1000    0.0400    0.0100     -0.0543    0.0876    0.0328
           19    0.1000   -0.0600   -0.2000      0.0511   -0.2182    0.0581
           20    0.2000   -0.1500    0.3100      0.1283   -0.1846    0.3287
           21   -0.1000    0.0700    0.2000     -0.0947   -0.0306    0.2121
           23   -0.1300    0.1400    0.2500     -0.1390    0.0607    0.2757
           24   -0.1600    0.0800   -0.0300     -0.1170   -0.1289    0.0512
           25   -0.1200   -0.0100   -0.1000      0.0311    0.1531   -0.0088
           28    0.8600    0.3400   -0.1900     -0.0678   -0.3236    0.8843

              Ephemeris Difference:  1992  7  4  0  0  0.0000000

           PRN   DX(m)     DY(m)     DZ(m)       DR(m)     DT(m)     DN(m)

            2    0.4800   -0.5600    0.0100      0.2653   -0.2821    0.6278
            3    0.6000    0.1700    0.5600      0.1012    0.6132    0.5624
           11    0.4900   -0.1000   -0.3800      0.0269   -0.5745    0.2524
           12    1.0600    0.0300   -0.5300     -0.2716    1.0490    0.4810
           13    0.1500    0.0400   -0.3300      0.1082    0.3183    0.1413
           14    0.0100   -0.0200    0.3500      0.0276   -0.3492    0.0176
           15    0.5600   -0.1700    0.1700      0.0038   -0.5575   -0.2461
           16    0.2500   -0.2600   -0.5800     -0.1073   -0.4996   -0.4532
           17   -0.1900    0.1000    0.1700      0.1831    0.1256    0.1603
           18   -0.0500    0.3400    0.0000      0.0293    0.3084   -0.1487
           19   -0.0900    0.0000    0.3000      0.0024    0.3121    0.0266
           20    0.3100   -0.2400    0.3000      0.0796   -0.1967    0.4457
           21    0.6400   -0.7500   -0.5000     -0.0428    0.3045   -1.0619
           23    0.2300    0.5200   -0.3300     -0.1773   -0.6318    0.0403
           24   -0.3400   -0.2200    0.0600     -0.0014   -0.3486   -0.2147
           25    0.8000    0.3900    0.3200     -0.4233   -0.7250   -0.4355
           28   -0.4800   -0.4000   -0.6400     -0.0370   -0.5930   -0.6686

The independent one day arcs used for the Earth rotation solutions have
the characteristics given below:

   UTX06517.ERP    
                        Day->      0     1     2     3     4     5     6

     Passes:                     350   371   398   382   392   392   350*
     Double differences (DD):  17178 18652 18863 19573 19320 19176 18954*
     RMS of DD (cm):             1.4   1.5   1.9   1.9   2.1   2.2   2.3*
       [Day 0=Sunday; Day 6=Saturday)
       All satellites included for each day
       *The reported Earth rotation solution excluded PRN12; without PRN12
         the RMS is 1.77 cm with 302 passes.  PRN12 is included in ephemeris
         file.
----------------------------
For further information:
   Prof. B. E. Schutz
   [email-masked]

or Dr. P. A. M Abusali
   [email-masked]