[IGSMAIL-6818] igs08_1755.atx: Update including reactivated Block IIA satellite SVN32/PRN30

[Robert Khachikyan]

Dear IGS colleagues!

The absolute IGS antenna correction file (igs08_wwww.atx) has been 
updated. The new release is called 'igs08_1755.atx'. It contains the 
following changes:

1) According to Richard Langley, Block IIA satellite SVN32 started 
transmitting signals as PRN30 on 22 August 2013. Therefore, the 
following satellite has been added to igs08.atx:

G30 (G032)

Sources:

> SVN32 began transmitting signals as PRN30 at about 23:15:30 GPST on 22 
> August (day 234) 2013 as monitored by a number of the tracking 
> stations participating in the International GNSS Service's Multi-GNSS 
> Experiment.
https://listserv.unb.ca/cgi-bin/wa?A2=CANSPACE;2e634e8c.1308

> NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2013049 NANU TYPE: GENERAL
> *** GENERAL MESSAGE TO ALL GPS USERS ***
> On approximately 22 AUG 2013 SVN32 will resume transmitting L-band
> utilizing
> PRN30. At L-band activation, SVN32/PRN30 will be unusable until further
> notice.  Additionally, no broadcast almanacs will include SVN32/PRN30
> until
> further notice.
http://cgls.uscg.mil/pipermail/nanu/2013-August/001520.html

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

G30 (G049): 21 August 2013


The updated antenna correction model is available at
ftp://igs.org/pub/station/general/igs08_1755.atx
or
ftp://igs.org/pub/station/general/igs08.atx

Those who still didn't switch to the GPS satellite antenna PCV extension 
can use the following model instead:
ftp://igs.org/pub/station/general/igs08_1755_woPCVextension.atx
This is the last parallel file! In the future, only models including the 
PCV extension will be provided.

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