[IGSMAIL-6899] igs08_1788.atx: Update including GLONASS-M satellite R754

[Ralf Schmid]

Dear IGS colleagues!

The absolute IGS antenna correction file (igs08_wwww.atx) has been 
updated. The new release is called 'igs08_1788.atx'. It contains the 
following changes:

1) A GLONASS-M satellite launched on 23 March 2014 was added with a 
preliminary z-offset value of 245 cm:

R18 (R754)

2) A decommission date for the following satellite has been added:

R18 (R714): 10 April 2014

Obviously, both satellites transmitted signals on DOY 101 (11 April 
2014) and DOY 102 (12 April 2014). As more observation data seems to be 
available for R754, those two days were attributed to the newly launched 
satellite for the time being. This could be changed later on.


Sources:

NAGU 022-140411:
> NOTICE ADVISORY TO GLONASS USERS (NAGU) 022-140411
> SUBJ: 18/-6 (714) SPARES 11.04/0010-11.04/1035 MT
> 1.CONDITION: 18/-6 (714) SPARES
>  SINCE 11.04/0010 UNTIL 11.04/1035 MT (UTC+0300)

NAGU 023-140411:
> NOTICE ADVISORY TO GLONASS USERS (NAGU) 023-140411
> SUBJ: FORECAST PUT INTO OPERATION 18/-3 (754)  ON 19.04
> 1.CONDITION: 18/-3 (754) IS SCHEDULED TO BE OPERATION ON 19.04
> AFTER MAINTENANCE
http://glonass-iac.ru/en/CUSGLONASS/index.php


The updated antenna correction model is available at
ftp://igs.org/pub/station/general/igs08_1788.atx
or
ftp://igs.org/pub/station/general/igs08.atx

Many thanks to Richard Langley and Stefan Schaer for their help!

With best regards,
Ralf Schmid
on behalf of the IGS Antenna Working Group