OPUS, CORS, etc. for October

November 3, 2009

OPUS STATISTICS

Total number of monthly solutions for OPUS-S and OPUS-RS are graphically
displayed at:

        http://www.ngs.noaa.gov/OPUSI/Plots/OPUS.jpg

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November 3, 2007

FROM THE NEWS: SATELLITE GPS 2R-20 HAVING PROBLEMS

Satellite Beset by Permanent Signal Problem
BY: STEPHEN CLARK
Spaceflight Now
02 November, 2009


A Global Positioning System satellite launched in March is suffering from
permanent
signal distortions and will miss its target to enter operational service this
year,
Air Force officials said. The GPS 2R-20 satellite, built by Lockheed Martin
Corp.,
is being kept from service because of signal distortions that are degrading the
accuracy of its navigation measurements. Officials said in June the problems
could
be fixed in time for the satellite to be introduced into the GPS fleet by this
fall,
but now the Air Force says the craft won't be ready until at least next year.

"The satellite's signal distortion is permanent, and if brought into
operational
service its impact on users would be variable and application-specific," said
a
Global Positioning Systems Wing spokesperson at the Air Force Space and
Missile
Systems Center.

There are 30 operational GPS satellites in space today, circling Earth in
orbits
more than 12,500 miles high and inclined about 55 degrees to the equator. The
fleet
is divided into six planes to provide uniform global coverage. Only four
satellites
in each plane, a total of 24 spacecraft are needed for uninterrupted service.

"The GPS constellation is the strongest it has ever been,allowing the Air
Force
time to focus on a long-term solution with minimal impact to users. We expect
ongoing efforts to bring the satellite into operations to run well into 2010,"
the SMC spokesperson said in a written statement.

Launched in March, the spacecraft was the first GPS platform to host the L5
demonstration payload for the civil aviation industry. The L5 instrumentation
was installed on an auxiliary port on the satellite, and that interface is
causing the signal interference, officials said earlier this year. The L5
payload was added to GPS 2R-20 to meet an August deadline imposed by the
International Telecommunications Union, which oversees radio frequency filings
for satellites. Engineers believe the trouble is specific to GPS 2R-20 because
the L5 signal will be attached to a different interface on the next-generation
GPS 2F series of satellites. The L5 instrument was also not on the GPS 2R-21
satellite launched in August. That spacecraft was put into service two weeks
after arriving in space.

The next GPS satellite launch is scheduled for next June, when the Air Force
will send the first of GPS 2F series craft into orbit on a Delta 4 booster.
That mission was recently delayed from February due to the unavailability of
a rocket and launch manifest constraints, according to the Air Force. Earlier
this year, the Government Accountability Office published a report saying the
GPS program faces reductions in service due to delays of the GPS 2F program
and schedule uncertainty on the long-term replacement fleet, called the
GPS 3A program.

GPS 3A satellites are now slated to begin launching in 2014. "The current GPS
constellation has the most satellites and the greatest capability ever. We are
committed to maintaining our current level of service, as well as striving to
improve service and capability through on-going modernization efforts," a GPS
Wing spokesperson said.

The Air Force says there will be no negative impacts on services for GPS
customers,
which include both military and civilian users. "The U.S Air Force and Air
Force
Space Command have been the diligent stewards of GPS since its conception in
the 1970s and continue its commitment to this critical component of our
National
Infrastructure," a GPS Wing spokesperson said. "The Air Force will continue to
pursue an achievable path maintaining GPS as the premier provider of
positioning,
navigation and timing for military and civilian users around the world,"
officials
said.

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November 3, 2009

GRAPHICAL DISPLAY OF OPUS-RS ACCURACIES (UPDATED WEEKLY)

To know the approximate accuracy of OPUS-RS solutions as a function of
geographic location, click the following two graphs:

a) 15 minutes session accuracy

Horizontal accuracy: http://www.ngs.noaa.gov/OPUSI/Plots/OPUSRSall-h.15-min.png

Ellipsoid height accuracy:
http://www.ngs.noaa.gov/OPUSI/Plots/OPUSRSall-u.15-min.png

b) 1 hour session accuracy

Horizontal accuracy: http://www.ngs.noaa.gov/OPUSI/Plots/OPUSRSall-h.1-hour.png

Ellipsoid height accuracy:
http://www.ngs.noaa.gov/OPUSI/Plots/OPUSRSall-u.1-hour.png

A brief description of how these graphs were generated is available at:

http://www.ngs.noaa.gov/OPUSI/Plots/OPUS-RSWebPlots.pdf

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November 3, 2009

OPUS COVERAGE BY COUNTY IN OCTOBER 2009

To see a plot of OPUS solutions in the US by county during October 2009
click at:
                
        http://www.ngs.noaa.gov/OPUSI/Plots/2009-10opus.gif
                        
To see a plot of OPUS-RS solutions in the US by county during October 2009
click at:
                
        http://www.ngs.noaa.gov/OPUSI/Plots/2009-10opus-rs.gif

The total OPUS coverage (OPUS + OPUS-RS) by county during a period of one year
can be seen at:
                        
        http://www.ngs.noaa.gov/OPUSI/Plots/2009-10_2008-11combined.gif

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November 3, 2009

CHANGE IN CORS ONLINE STORAGE

As we continue to streamline and improve our data distribution we plan to
change the number of files we distribute via our two ftp servers. We will only
keep RINEX files in both Hatanaka UNIX compressed format (d.Z) & gzipped (o.gz)
for 3 years. Currently we have both files for every site for the last 5 years.
This change will not result in any loss of data we will continue to provide
the complete set of RINEX files for all CORS from 1994 to present.

If you encounter any problems do let us know by sending an email:

ngs.cors @ noaa.gov

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November 3, 2009

FTP AND UFCORS STATISTICS FOR OCTOBER 2009

FTP server statistics for Oct 2009
Total Requests: 598145 (all FTP requests logged)
Total Data Transferred: 397984 MB (all files)

Requests for RINEX data: 492665 (82% of total requests)
2009 data: 332551 (67% of RINEX requests)
2008 data: 46699 ( 9% of RINEX requests)
2007 data: 7766 ( 1% of RINEX requests)
2006 data: 56563 (11% of RINEX requests)
2005 data: 10711 ( 2% of RINEX requests)
2004 data: 3987
2003 data: 2722
2002 data: 899
2001 data: 26920 ( 5% of RINEX requests)
2000 data: 374
1999 data: 63
1998 data: 1754
1997 data: 764
1996 data: 776
1995 data: 82
1994 data: 34

Requests for daily files. Requests for hourly files.
Total: 362663 - 244389 MB Total: 98097 - 3726 MB
Obs: 81256 - 182219 MB Obs: 5191 - 2327 MB
Nav: 0 - 0 MB Nav: 0 - 0 MB
Met: 60 - 0 MB Met: 1595 - 1 MB
Sum: 3478 - 0 MB Sum: 1337 - 0 MB
Other: 277869 - 62102 MB Other: 89974 - 1387 MB

Requests for ephemerides files.
IGR: 1092 - 92 MB
IGS: 911 - 75 MB
IGU: 2667 - 439 MB
Brdc: 26129 - 1347 MB

Other files: 1106 - 81379 MB


Requests from top 10 hosts (% of RINEX requests):
ttc-tps.topconps.org: 99896 (20%) - 7388 MB ( 2%)
d206-088.geology.wisc.edu: 51083 (10%) - 16634 MB ( 5%)
atlas.haystack.edu: 46985 ( 9%) - 36054 MB (10%)
geoback.nbmg.unr.edu: 46658 ( 9%) - 14025 MB ( 4%)
sedna.unibe.ch: 46089 ( 9%) - 733 MB ( 0%)
matara.ucar.edu: 29773 ( 6%) - 611 MB ( 0%)
carina1.cosmic.ucar.edu: 23380 ( 4%) - 1068 MB ( 0%)
sikanni.pgc.nrcan.gc.ca: 22644 ( 4%) - 17724 MB ( 5%)
tokonda.ucar.edu: 14917 ( 3%) - 286 MB ( 0%)
host2.sokkia.co.jp: 14522 ( 2%) - 207 MB ( 0%)
geostor01.ucsd.edu: 11813 ( 2%) - 3505 MB ( 1%)

Total: 407760 (82%) - 98240 MB (29%)

Plots for "user friendly" CORS (UFCORS) requests for last month are available at
the following Web address:

http://www.ngs.noaa.gov/CORS-Proxy/UfcorsLogStatistics/corsstatisticsv3?month=Oct&year=2009

Month by month statistics can be viewed at:

http://www.ngs.noaa.gov/CORS-Proxy/UfcorsLogStatistics/corsstatisticsv3?month=All&year=2009

http://www.ngs.noaa.gov/CORS-Proxy/UfcorsLogStatistics

A graphic display of FTP and UFCORS activity is available at:

http://www.ngs.noaa.gov/OPUSI/Plots/CORS.jpg

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