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Dear IGS colleagues!
<br>
<br>
In preparation for the second IGS reprocessing campaign "repro2",
the absolute IGS antenna correction file (igs08_wwww.atx) has been
updated. The new release is called 'igs08_1706.atx' and should be
used starting with GPS week 1706 (16 September 2012). It contains
the following changes:
<br>
<br>
1) The z-offsets of two GPS and five GLONASS satellites have been
changed using estimates provided by Paul Rebischung (IGN) based on
operational SINEX files of six ACs. Five of the satellites were only
launched after the release of igs08.atx, the z-offset values
available for the first Block IIF satellite G062 (launched in May
2010) and for the first GLONASS-K1 satellite R801 (launched in
February 2011) were only based on few data:
<br>
<br>
G062/G25: 1.6632 m --> 1.5973 m
<br>
G063/G01: 1.6500 m --> 1.5613 m
<br>
R742/R04: 2.4500 m --> 2.3811 m
<br>
R744/R03: 2.4500 m --> 2.5631 m
<br>
R745/R07: 2.4500 m --> 2.6372 m
<br>
R746/R17: 2.4500 m --> 2.7436 m
<br>
R801/R03: 1.7500 m --> 2.0668 m
<br>
R801/R04: 1.7500 m --> 2.0668 m
<br>
R801/R26: 1.7500 m --> 2.0668 m
<br>
<br>
More details can be found in the following table (all values in
[m]):
<br>
<br>
| Sat. | AC | # wk | w.mean | w.rms |<b class="moz-txt-star"><span
class="moz-txt-tag">*</span>AC mean<span class="moz-txt-tag">*</span></b>|
igs08 | d.igs08 |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| G062 | cod | 102 | 1.5808 | 0.0221 | 1.5973 | 1.6632 | -0.0659 |
<br>
| G062 | emr | 81 | 1.6190 | 0.0258 | | | |
<br>
| G062 | esa | 102 | 1.5901 | 0.0240 | | | |
<br>
| G062 | gfz | 99 | 1.5986 | 0.0303 | | | |
<br>
| G062 | mit | 98 | 1.5875 | 0.0277 | | | |
<br>
| G062 | ngs | 93 | 1.6078 | 0.0241 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| G063 | cod | 54 | 1.5596 | 0.0344 | 1.5613 | 1.6500 | -0.0887 |
<br>
| G063 | emr | 43 | 1.5689 | 0.0208 | | | |
<br>
| G063 | esa | 54 | 1.5520 | 0.0225 | | | |
<br>
| G063 | gfz | 44 | 1.5477 | 0.0221 | | | |
<br>
| G063 | mit | 51 | 1.5451 | 0.0251 | | | |
<br>
| G063 | ngs | 38 | 1.5946 | 0.0177 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| R742 | cod | 43 | 2.3805 | 0.0288 | 2.3811 | 2.4500 | -0.0690 |
<br>
| R742 | esa | 42 | 2.3816 | 0.0369 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| R744 | cod | 36 | 2.5609 | 0.0322 | 2.5631 | 2.4500 | +0.1131 |
<br>
| R744 | esa | 36 | 2.5653 | 0.0437 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| R745 | cod | 35 | 2.6413 | 0.0294 | 2.6372 | 2.4500 | +0.1872 |
<br>
| R745 | esa | 35 | 2.6330 | 0.0322 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| R746 | cod | 34 | 2.7655 | 0.0322 | 2.7436 | 2.4500 | +0.2936 |
<br>
| R746 | esa | 33 | 2.7217 | 0.0327 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
| R801 | cod | 20 | 2.0908 | 0.0246 | 2.0668 | 1.7500 | +0.3168 |
<br>
| R801 | esa | 17 | 2.0427 | 0.0448 | | | |
<br>
|------|-----|------|--------|--------|---------|--------|---------|
<br>
<br>
The corresponding time series can be found at
<br>
<a class="moz-txt-link-freetext"
href="ftp://igs-rf.ensg.eu/pub/IGS08/new_z-PCOs">ftp://igs-rf.ensg.eu/pub/IGS08/new_z-PCOs</a>
or
<br>
<a class="moz-txt-link-freetext"
href="ftp://igs-rf.ign.fr/pub/IGS08/new_z-PCOs">ftp://igs-rf.ign.fr/pub/IGS08/new_z-PCOs</a>
<br>
<br>
All IGS results starting with GPS week 1706 will be based on the new
z-offset values. Sorry for any inconvenience this may cause!
<br>
<br>
2) The start date of the reactivated Block IIR-M satellite G049/G24
was corrected:
<br>
<br>
8 August 2012 --> 9 August 2012
<br>
<br>
Compare [IGSMAIL-6644]: SVN49 reactivated
<br>
<a class="moz-txt-link-freetext"
href="http://igscb.jpl.nasa.gov/pipermail/igsmail/2012/006636.html">http://igscb.jpl.nasa.gov/pipermail/igsmail/2012/006636.html</a>
<br>
In the meantime, this satellite already stopped transmissions again:
<br>
<a class="moz-txt-link-freetext"
href="https://listserv.unb.ca/cgi-bin/wa?A2=CANSPACE;c52129cb.1208">https://listserv.unb.ca/cgi-bin/wa?A2=CANSPACE;c52129cb.1208</a>
<br>
<br>
<br>
Although not valid before 16 September 2012, the updated antenna
correction model is already available at
<br>
<a class="moz-txt-link-freetext"
href="ftp://igs.org/pub/station/general/igs08_1706.atx">ftp://igs.org/pub/station/general/igs08_1706.atx</a>
<br>
<br>
Many thanks to Paul Rebischung for all his efforts!
<br>
<br>
With best regards,
<br>
Ralf Schmid and Robert Khachikyan
<br>
on behalf of the IGS Antenna Working Group
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