Subject: [IGSMAIL-1299] Station Report
From: J F Zumberge
Date: Wed, 1 May 1996 13:41:07 PDT

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IGS Electronic Mail      Wed May  1 13:41:07 PDT 1996      Message Number 1299
******************************************************************************

Author: J F Zumberge
Subject: Station Report

Date:   May 1, 1996
To:     IGS Colleagues

Beginning today, as part of the Central Bureau's (CB) task to
"...monitor network operations and quality assurance of data..."  (IGS
Terms of Reference), daily and weekly Station Reports are generated by
the Satellite Geodesy and Geodynamics Systems Group at JPL for the CB.
These are available at igscb.jpl.nasa.gov.  For example

  netscape ftp://igscb.jpl.nasa.gov/igscb/mail/igsnet/weekly/1996-04-21.gz

will display the report for seven days beginning April 21, 1996, and

  netscape ftp://igscb.jpl.nasa.gov/igscb/mail/igsnet/daily/1996-04-25.gz

will display the report for the single day April 25, 1996.

(Of course, regular anonymous ftp can be used to retrieve files.  Once
logged on to igscb.jpl.nasa.gov, cd to /igscb/mail/igsnet/daily for
daily reports or /igscb/mail/igsnet/weekly for weekly reports.)

Every Wednesday for the week that ended the previous Saturday, a weekly
report is distributed to IGS station operators, the Governing Board, AC
and AAC personnel, and Data Center personnel.  The first such report was
mailed earlier today.  (If you want to be added to or removed from the
distribution list, send your request to [email-masked].)

Documentation can be found in

   ftp://igscb.jpl.nasa.gov/igscb/data/network/igsnet.doc

which is included below for your convenience.

Sincerely,

Jim Zumberge
________________________________________________________________________
96/04/05
J F Zumberge                                      [email-masked]

This   document   describes   the  Station   Report  that  is  generated
periodically  for the IGS Central Bureau by JPL's Satellite  Geodesy and
Geodynamics System (SGGS) Group, based on Rinex data provided by the GPS
Networks and Operations (GNO) Group.  An example is given in Table 1.

There are four numeric  fields:  "overall",  "quantity",  "quality", and
"latency".  Each is a floating  point  number,  although the results are
rounded to the nearest integer.  The overall field is the average of the
other three fields. The highest and best value for each field is 10.

Before  describing how these numbers are computed, we first refer to the
procedure announced in IGS mail 1187, (Jan 16, 1996):

      Rapid  precise  GPS  orbit  and  clock  solutions  are  now
      available  from JPL in sp3  format  (see  below for  access
      details) within about 20 hours of the close of the UTC day.
      These rapid orbits  typically  agree with the final JPL IGS
      orbit to about 20 cm rms.  Earth orientation is adjusted in
      these solutions and reported to the IGS, IERS, and USNO.

      These  solutions are used to compute rapid  solutions  from
      over 100 sites daily, including all SCIGN sites in southern
      California.  These rapid positions typically agree with our
      final  positions at the sub-cm  level.  Publicly  available
      Rinex  data from new sites will be  processed  as the sites
      become operational.  Results are available upon request for
      sites of interest.

      A  3-day  predicted  orbit  is also  available  in the  sp3
      format.  Because of the rapid  turn-around, this means that
      a real-time  orbit, based on  extrapolations  of between 20
      and 44 hours, is available, with an accuracy  significantly
      better  than the  broadcast  orbits.  We find  that 24 hour
      predicted  orbits  are  typically  50-80  cm,  and 48  hour
      predictions generally 1-2 meters.

      The  final  JPL IGS orbit  and  Earth  orientation  are now
      computed  with a 4 day  lag  (access  details  below).  All
      sites are also  processed  using  this  final  orbit,  with
      ambiguities resolved for regional networks.

One of the results of the "rapid solutions" mentioned in this excerpt is
shown in Table 2.  (Several  of the  fields  in the full  database  from
which   Table   2  was   extracted   can  be   viewed   graphically   at
http://milhouse/eng/eng.html.)  There  is one  rapid  solution  for each
site on each day (assuming  that the Rinex file has been made  available
to the SGGS Group by the GNO Group).  The phase and pseudorange data are
used to  estimate  the  usual  receiver-specific  parameters:  Cartesian
coordinates,  receiver clock, and zenith troposphere delay.  Transmitter
parameters -- satellite  positions and clock corrections -- are fixed at
their values determined in the rapid global solution.

In Table 2, the "number of time tags for which clock  solution is valid"
field,  call it N,  reflects  data  availability.  The normal  data rate
analyzed  is 5 minutes;  there are thus 288 times in a 24-hr  period for
which data exists.  The value of the "quantity" field is therefore

                              quantity = <N>/28.8,

where <N> is the average value of N over the period of interest, usually
1 week.  This  number can be less than 10 if either (a) one or more days
of data are  missing  or (b)  some of the data  have  been  rejected  as
outliers.

The quality  field is also the average  over one or more days of a daily
quality   figure.  The  daily   quality   figure  is  based  on  several
categories.  One  quality  point is awarded  on each day for each of the
following conditions:

  - there are at least 250 valid clock solutions

  - there are fewer than 100 phase bias resets (the last
    field in Table 2)

  - the 3d formal error of the solution for station location
    is less than 1 cm (this field is not in Table 2, but is
    in a related database)

  - the pseudorange rms residuals (field 8 in Table 2) are
    less than 86 cm (this is true 95% of the time), and the
    number of pseudorange measurements is at least 90% of
    the number of phase measurements

  - the phase rms residuals (field 10 in Table 2) are less
    than 13 mm (also true 95% of the time)

Thus a site  can be  awarded  up to 5  quality  points  every  day.  The
quality field is thus

                               quality = <P>/0.5,

where  <P> is the  average  number  of points  awarded  over the  period
(again, typically a week) reported.

The latency  field  measures the delay between the  beginning of data in
the file and the  availability  of the file, minus 1 day to account  for
the span of the data.  A latency  database is maintained for each of the
three IGS Global Data  Centers.  The latency for a given site and day is
the minimum value from the three centers.  (If no centers have the data,
then the latency is based on the GNO value.)  Very late or missing files
are assumed to have a latency of 100 hr.  The latency is calculated as

                             latency = 10 - <H>/10,

where <H> is the average latency, in hours, over the period.

[A subset of engineering data -- like shown in Table 2 -- can be made
available on request.  Questions/comments should be directed to me at
the e-mail address listed above.]

_______________________________________________________________________________
Table 1  Example of Station Report
------------------------------------------------------------------------------
_____________________________________________________________________
Station Report for 7 days beginning 1996-03-24
(generated 1996-04-05 09:38)

NOTICE:  The information listed below results from JPL IGS Analysis
Center procedures based on Rinex data available from JPL's GPS Networks
and Operations Group, and does not necessarily reflect the operational
quality of any site.

For all numeric fields, a 10 is the highest (and best), a 0 is the
lowest.  The "overall" field is the average of the quantity, quality,
and latency fields.  The "quantity" field indicates how much usable data
from the site was available.  The "quality" field accounts for amount of
data, number of phase breaks, formal errors of (precise)
point-positioned coordinates, and pseudorange and phase residuals.  The
"latency" field will be 10 for a site whose data are available, on
average, within 5 hours of the end of the GPS day.  It will be reduced
by 1 point for each additional 10 hours of delay.  (More detailed
information can be found in
ftp://igscb.jpl.nasa.gov/igscb/data/network/igsnet.doc.)

_____________________________________________________________________
IGS Fiducial Sites
site   overall     quantity  quality  latency    agency     location
---------------------------------------------------------------------
algo       10          10       10        9      NRCan-GSD  Canada  
fair        8           9        7        9      JPL        USA  
gold        8           8        7        7      JPL        USA  
hart        0           0        0        0      CNES       South Africa 
kokb       10          10       10       10      JPL        USA  
kosg       10          10        9        9      DUT        The Netherlands 
madr        9           9        7        9      JPL        Spain  
sant        9          10        8        9      JPL        Chile  
tidb        8           8        6        9      JPL        Australia  
trom        6           6        5        8      NMA        Norway  
wett        8           9        7        9      IfAG       Germany  
yar1        9          10        8        9      JPL        Australia  
yell        9           8        9        9      NRCan-GSD  Canada  
_____________________________________________________________________
Other IGS Global Sites
site   overall     quantity  quality  latency    agency     location
---------------------------------------------------------------------
albh       10          10       10        9      NRCan-GSC  Canada  
ankr        8          10       10        5      IfAG       Turkey  
areq        9          10       10        8      JPL        Peru  
bor1       10          10       10        9      SRC-PAS    Poland  
brmu        9           9        9       10      NOAA       USA  
brus       10          10       10        9      ROB        Belgium  
cas1        8           9        9        7      AUSLIG     Antarctica  
chat        7           7        7        6      JPL        New Zealand 
fort        9          10        9        8      NOAA       Brazil  
guam        9          10       10        8      JPL        Guam  
hob2        0           0        0        0      AUSLIG     Australia  
iisc        9           9        8        9      JPL        India  
irkt        8           9        9        5      DUT        Russia  
kely        4           2        3        5      NOAA       Greenland  
kerg        9          10        8        9      CNES       Kerguelen Islands 
kiru       10          10        9       10      ESA        Sweden  
kit3        6           7        7        5      GFZ        Uzbekistan  
kour        8           9        6       10      ESA        French Guiana 
lpgs        5           5        5        5      GFZ        Argentina  
mac1        4           4        4        4      AUSLIG     Australia  
mali        7           8        5        9      ESA        Kenya  
mas1        4           3        2        7      ESA        Spain  
mate        7           7        5        8      ASI        Italy  
mcm4       10          10       10        9      JPL        Antarctica  
mdo1        9           9       10        7      JPL        USA  
mdvo        8           8        8        7      DUT        Russia  
mets        7           6        6        8      FGI        Finland  
nlib       10          10       10        9      JPL        USA  
ohig        6           7        7        4      IfAG       Antarctica  
onsa        8           7        7        9      OSO        Sweden  
pama        7           8        5        8      CNES       Tahiti  
pert        9           9        9       10      ESA        Australia  
pie1       10          10       10        9      JPL        USA  
pots        8           9        7       10      GFZ        Germany  
rcm5        9           9        8       10      NOAA       USA  
sey1        0           0        0        0      JPL        Seychelles  
shao        9          10        8        8      JPL        China  
stjo       10          10       10        9      NRCan-GSD  Canada  
taiw        8           9        7       10      IES-AS     Taiwan  
thu1        9           9        9        9      JPL        Greenland  
tskb       10          10       10        9      GSI        Japan  
usud       10          10       10        9      JPL        Japan  
vill       10          10       10       10      ESA        Spain  
zwen        6           6        5        7      GFZ        Russia  
_____________________________________________________________________
Other IGS Sites (retrieved by JPL)
site   overall     quantity  quality  latency    agency     location
---------------------------------------------------------------------
aoa1       10          10       10        9      JPL        USA  
auck        8           9        9        7      JPL        New Zealand 
blyt       10          10       10        9      SIO        USA  
bogt        9           9        9        9      JPL        Columbia  
bran        5           6        5        4      USGS-SIO   USA  
braz        0           0        0        0      IBGE-JPL   Brazil  
carr       10          10       10        9      JPL        USA  
casa        9           9        7        9      JPL        USA  
cat1       10          10       10        9      JPL        USA  
chil        8           9        9        6      USGS-SIO   USA  
cit1       10          10       10        9      JPL        USA  
coso        9           9        9       10      SIO        USA  
crfp        9           9        9        9      SIO        USA  
cro1       10          10       10        9      NRAO-JPL   US Virgin Islands
dav1        5           4        4        5      AUSLIG     Antarctica  
drao       10          10       10        9      NRCan-GSC  Canada  
ebre        2           3        3        1      ICC        Spain  
eisl        9          10        9        9      JPL        Chile  
gode       10          10       10        9      NASA-GSFC  USA  
gope        9           9        9        8      RIG        Czech Republic 
gras        9          10       10        7      CNES       France  
graz        8           8        7        9      ISR        Austria  
harv       10          10       10        9      JPL        USA  
hers        8           9        7        8      RGO        United Kingdom 
holc        8          10       10        4      USGS-SIO   USA  
joze        9          10       10        8      IGGA-WUT   Poland  
jplm       10          10       10        9      JPL        USA  
lama        0           0        0        0      OUAT       Poland  
lbch       10          10       10        9      JPL        USA  
lhas        0           0        0        0      IfAG       China  
long        5           6        4        5      USGS-SIO   USA  
math        7          10       10        0      SIO        USA  
monp        8           7        8        9      SIO        USA  
noto        8          10       10        5      ASI        Italy  
nyal        8           8        7        8      NMA        Norway  
oat2       10          10       10        9      JPL        USA  
pin1        8           9        9        8      SIO        USA  
pol2        7           7        7        7      UNAVCO     Kyrgyzstan  
pvep        9          10        7        9      SIO        USA  
quin       10          10       10        9      JPL        USA  
reyk        6           4        4        9      IfAG       Iceland  
sio3       10          10       10        9      SIO        USA  
sni1        0           0        0        0      JPL        USA  
spk1       10          10       10        9      JPL        USA  
taej        8           6        7       10      KAO        Korea  
trak        8           9        7        8      SIO        USA  
uclp       10          10       10        9      JPL        USA  
upad        6           7        7        5      UP         Italy  
usc1       10          10       10        9      JPL        USA  
vndp        9           9       10        9      SIO-JPL    USA  
wes2        9           9       10       10      NOAA       USA  
whc1        9          10       10        9      JPL        USA  
whi1        9          10        9        9      JPL        USA  
wlsn       10          10       10        9      JPL        USA  
wtzr       10          10       10        9      IfAG       Germany  
zimm        9           9        8        9      FOT        Switzerland  
_____________________________________________________________________
Other IGS Sites (not retrieved by JPL)
site                                             agency     location
---------------------------------------------------------------------
cagl                                             ASI        Italy  
hflk                                             ISR        Austria  
medi                                             ASI        Italy  
roch                                             SIO        USA  
sfer                                             ROA        Spain  
_____________________________________________________________________
Other Sites (no log file at IGS CB)
site   overall     quantity  quality  latency    agency     location
---------------------------------------------------------------------
brib.       9          10        9        9      USGS       USA  
chab.       7          10        9        3      USGS       USA  
cice.      10          10       10        9      JPL        Mexico  
clar.       8          10        8        6      USGS       USA  
cmbb.       0           0        0        0      USGS       USA  
cmp9.       8          10       10        6      USGS       USA  
dam1.       7           8        9        3      USGS       USA  
dam2.       5           4        4        6      USGS       USA  
denc.       0           0        0        0      CORS       USA  
fai2.      10          10       10        9      JPL        USA  
farb.       9          10       10        7      USGS       USA  
gol2.      10          10       10        9      JPL        USA  
hbrk.       3           0        0       10      CORS       USA  
hklo.       3           0        0       10      CORS       USA  
holp.       8          10       10        6      USGS       USA  
hopb.       6           4        4        9      USGS       USA  
krak.       3           0        0        8      JPL        USA  
leep.       8          10       10        5      USGS       USA  
lmno.       3           0        0       10      CORS       USA  
moin.       3           0        0        9      JPL        Costa Rica 
mola.       8          10       10        4      USGS       USA  
nune.       8          10       10        4      USGS       USA  
pltc.       3           0        0       10      CORS       USA  
rock.       8          10       10        5      USGS       USA  
sol1.       9           9        9        9      NOAA/NASA  USA  
strl.       3           0        0        9      CORS       USA  
tabl.       4           3        3        5      USGS       USA  
tibb.       6           4        4        9      USGS       USA  
tid2.      10          10       10        9      JPL        Australia  
tmgo.       8           7        7        9      CORS       USA  
usna.       9           9        9        9      NOAA/NASA  USA  
vcio.       3           0        0       10      CORS       USA  
wint.       8          10       10        3      USGS       USA  
wlps.       3           0        0        9      CORS       USA  
wsmn.       3           0        0       10      CORS       USA  
_____________________________________________________________________
_______________________________________________________________________________

_______________________________________________________________________________
Table 2  Engineering data for precise-point-positioned sites
-------------------------------------------------------------------------------

 date
 |          site
 |          |     number of time tags for which clock solution is valid
 |          |     |   rms deviation from straight line of clock solution (ns)
 |          |     |   |         drift of clock solution (parts per trillion)
 |          |     |   |         |         clock solution at noon (usec)
 |          |     |   |         |         |         # of pseudorange meas.
 |          |     |   |         |         |         |     rms (cm)
 |          |     |   |         |         |         |     |   # of phase meas.
 |          |     |   |         |         |         |     |   |     rms (mm)
 |          |     |   |         |         |         |     |   |     |   orig
 |          |     |   |         |         |         |     |   |     |   |    tot
 |          |     |   |         |         |         |     |   |     | <-breaks->
 |________  |___  |_  |_______  |_______  |_______  |___  |_  |___  |_  |_   |_
...
1996-02-25 IISC  288      69.9     0.247  -0.00443  1677  70  1675  13  69   69
1996-02-25 IRKT  287       147      9.47    -0.214  1650  46  1650   8  51   51
1996-02-25 JOZE  286      36.2     -94.8       181  1653  50  1653   7  39   39
1996-02-25 JPLM  288      41.7       114   1.4e+03  1667  26  1667   6  44   47
1996-02-25 KERG  288      70.9      7.06      -660     0   .  1552   5  53   53
1996-02-25 KIRU  288      3.08  -0.00867      11.7  1427  50  1427  10  67   80
1996-02-25 KIT3  288       126    0.0974   -0.0181  1642  66  1642  11  47   47
1996-02-25 KOKB  288     0.131     0.366   0.00596  1661  55  1661   6  45   50
1996-02-25 KOSG  288      1.02     -3.94      20.5  1324  38  1324   5  44   44
...
_______________________________________________________________________________
96/04/05                /users/igscb/work/data/network/SCCS/s.igsnet.doc

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