[IGSMAIL-4929]: GPS Time Series

[Michael B Heflin]

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IGS Electronic Mail      21 Apr 13:54:04 PDT 2004      Message Number 4929
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Author:  M B Heflin

JPL's GPS time series web page was announced as a service to the geodetic
community on November 29, 1994.  Results have been updated roughly every
six months.  The current solution includes more than one million station-days
of GPS data for the first time and is based on roughly 7.2 billion phase and
range measurements from more than 900 globally distributed receivers.

GPS hardware and software have evolved dramatically over the last decade and
maintaining a stable reference frame in spite of all the changes has been
a major challenge.  These results make use of a transformative approach to
reference frame stability based on daily alignment instead of a fiducial
approach based on daily constraints.  All results are reported in ITRF2000.

The updated GPS time series data set is now available at URL:

http://sideshow.jpl.nasa.gov/mbh/series.html

Recent improvements include:
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Point positioned results for 905 sites:  IGS, SCIGN, BARD, CORS, NBAR, and PANGA
Time span 13.2 years:  91JAN23 through 04MAR31
Station-days of GPS data:  1110230 

Ambiguity resolved, regionally filtered results for 301 sites:  SCIGN
Time span 8.2 years:  96JAN01 through 04MAR31
Station-days of GPS data:  371097 

Position and velocity estimates
Polar motion and length of day time series
Geocenter and scale time series

All days prior to 95APR06 have been reprocessed
All results given in the ITRF2000 reference frame
Numerical results available via anonymous ftp