Subject: [IGSSTATION-3649]: R23 almanac problem fixed
From: Schaer Stefan LT <[email-masked]>
To: "[email-masked]'" <[email-masked]>, "[email-masked]'" <[email-masked]>
Cc: "[email-masked]'" <[email-masked]>, "[email-masked]'" <[email-masked]>
Date: Tue, 6 Apr 2010 15:04:31 +0200

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IGS Station Mail          06 Apr 06:04:47 PDT 2010      Message Number 3649
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Author: Stefan Schaer

Dear IGS colleagues,

The R23 tracking failure reported in IGS Mail 6123

http://igscb.jpl.nasa.gov/mail/igsmail/2010/msg00071.html

was caused by an almanac problem (wrong Tau-n value broadcast by the
GLONASS constellation). The JPS and TPS receiver models we listed in
IGS Mail 6123 do not allow sampling of satellites with inconsistent
almanac information (inconsistent to ephemeris information).

The causative GLONASS almanac problem was finally corrected on 1 April
2010 (day 091) by the GLONASS system operators:

ftp://ftp.unibe.ch/aiub/igsdata/y2010/odata_glonass_d090.txt
ftp://ftp.unibe.ch/aiub/igsdata/y2010/odata_glonass_d091.txt

Meanwhile, R23 is sampled by all GLONASS-capable receivers of the IGS.

Many thanks to Sergei Yudanov (Javad) for his assistance.

Best regards,

Stefan Schaer