[IGSMAIL-5696]: ESOC IGS Analysis Change!

[Tim.Springer at esa.int]

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IGS Electronic Mail      01 Feb 06:21:32 PST 2008      Message Number 5696
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Author: Tim Springer


Dear IGS Colleagues,

A little bit later today we will submit our "brand new" IGS final 
products. From now on (GPS week 1463) our IGS final products will based on 
our new software Napeos. Our Rapid and Ultra-Rapid IGS products will still 
be moved over to our new software by the end of February.

A few specifics about our solutions.
The orbits are based on 24-hour data spans.
The ERP parameters are estimated as offset and drift per day without any 
constraints at the day boundaries.
The Sinex solution is based on stacking seven 24-hour solutions (so not 
data overlap what so ever).
Our Sinex files contain the fully unconstrained normal equation system and 
also our (constrained) solution
Our "esa" IGS products are based on GPS only
Our "esx" IGLOS products are based on GPS and Glonass and contain the 
orbits and clocks of both systems

Currently we make two "full" solutions. One based on only GPS data, the 
other based on GPS and Glonass data. In the near future we will submit 
only the results from our GPS/Glonass combined solutions. However, at the 
moment we have a small problem with our GPS/Glonass Sinex files which is 
why our "esa" products are still "GPS only". The "esx" products are based 
on GPS/Glonass combined with both systems full estimated. The "esx" orbit 
files contain both GPS and Glonass satellites (I hope this is not a 
problem for the IGLOS combination). The GPS orbits are practically 
identical to the "esa" solution but not 100% the same.

We have taken a lot of care to test our new software. The new software has 
already been used within the Galileo Geodetic Service Provider (GGSP) 
project where it produces IGS Final like results (orbits, clocks, ERPs, 
and Sinex). It has also been used for reprocessing the first 3 months of 
the year 2000 in the framework of the IGS reprocessing efforts. 
Furthermore, the testing also included a reprocessing of the full year 
2007. The results of that reprocessing will be submitted as part of our 
IGS reprocessing efforts soon. Despite all these testing efforts it may 
still happen that there is something wrong with our products. So in case 
you notice anything strange with our new products, please, do contact us 
so that we can solve the problem ASAP.

Last but not least, we have  updated (or rather created from scratch) our 
Analysis Centre questionnaire and send it to the IGSCB. So it should be 
publicly available soon.

Kind regard,
Tim Springer on behalf of the ESA/ESOC GNSS Analysis Team


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Dr. Tim Springer
Navigation Support Office, OPS-GN (www.nng.esoc.de)
European Space Operations Centre
Robert Bosch Strasse 5
64293 Darmstadt
Germany
Tel: +49-6151-90-2029  Fax: +49-6151-90-3129