[IGSMAIL-7726] Re: igs14_2035.atx: Update including new GPS III satellite G074

[Florian Dilssner (POSITIM UG)]

Hi Arturo et al.,

We made a first attempt today to determine the orbit of SVN74 using all 
available L1/L2 tracking data collected by the IGS network over the last 
two days. The quality of the two daily orbit solutions we generated seems 
pretty ok but there is a strong elevation dependent signature in the 
carrier phase residuals that is obviously related to the missing satellite 
antenna PCV information in igs14_2035.atx (see green dots in "res.png").

Solving for the phase center parameters of SVN74 yields a mean z-offset of 
approx 1.93 m and a distinct PCV pattern with a peak-to-peak difference of 
about 27 mm. Enclosed plot  shows the PCV estimates as a function of the 
nadir angle (see "pcv.png" ).

Using the PCV corrections along with the associated z-offset virtually 
eliminates the systematics seen in the phase residuals (blue dots in 
"res.png"). The residual RMS goes from 11.8 mm to 9.7 mm and the 3D orbit 
overlap error between both arcs from 0.30 m to 0.08 m.

Can send you the PCVs if you like to include them into the next igs14.atx 
release.

Cheers
Florian




Florian Dilssner
Navigation Support Office, OPS-GN
European Space Operations Centre ESOC
Robert-Bosch-Str. 5, 64293 Darmstadt, Germany
Phone: +49-6151-90-4125 Fax: +49-6151-90-2908



From:   Arturo Villiger <arturo.villiger at aiub.unibe.ch>
To:     <igsmail at lists.igs.org>
Date:   09.01.2019 17:58
Subject:        [IGSMAIL-7724] igs14_2035.atx: Update including new GPS 
III satellite G074
Sent by:        "IGSMail" <igsmail-bounces at lists.igs.org>



Dear IGS colleagues,

The absolute IGS antenna correction file (igs14_wwww.atx) has been
updated. The new release is called 'igs14_2035.atx'. It contains the
following changes:


1) According to NANU 2019001 , BLOCK IIIA satellite SVN74 (2018-109A)
launched on 23 December 2018 was put into operation using PRN 04.
According to the Center for Orbit Determination in Europe (CODE), G074 
became
active on the 9 January 2019 (DOY 009).

Nanu 2019001:

NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2019001 NANU TYPE: GENERAL

*** GENERAL MESSAGE TO ALL GPS USERS *** GPS III SVN74 (PRN04) WAS 
LAUNCHED ON 23 DEC 2018 (2018 JDAY 357) AT 1351 ZULU. THIS SATELLITE 
WILL UNDERGO EXTENSIVE ON-ORBIT CHECK OUT AND TESTING PRIOR TO BEING SET 
HEALTHY.

A USABINIT NANU WILL BE SENT WHEN THE SATELLITE IS SET ACTIVE TO SERVICE.

https://www.navcen.uscg.gov/?Do=gpsShowNanu&num=2019001

The following PRELIMINARY phase center offset (PCO) values were assigned:

PCO_X = 0.0 cm
PCO_Y = 0.0 cm
PCO_Z = 170.0 cm


2) The following decommission date has been added:

   G04 (036):  02 January 2019


The updated antenna correction model is available at
ftp://ftp.igs.org/pub/station/general/igs14_2035.atx
or
ftp://ftp.igs.org/pub/station/general/igs14.atx

With best regards,
Arturo Villiger
on behalf of the IGS Antenna Working Group
_______________________________________________
IGSMail mailing list
IGSMail at lists.igs.org
https://lists.igs.org/mailman/listinfo/igsmail


This message is intended only for the recipient(s) named above. It may contain proprietary information and/or
protected content. Any unauthorised disclosure, use, retention or dissemination is prohibited. If you have received
this e-mail in error, please notify the sender immediately. ESA applies appropriate organisational measures to protect
personal data, in case of data privacy queries, please contact the ESA Data Protection Officer (dpo at esa.int).

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.igs.org/pipermail/igsmail/attachments/20190111/c0d98c02/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pcv.png
Type: image/png
Size: 64322 bytes
Desc: not available
URL: <http://lists.igs.org/pipermail/igsmail/attachments/20190111/c0d98c02/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: res.png
Type: image/png
Size: 207067 bytes
Desc: not available
URL: <http://lists.igs.org/pipermail/igsmail/attachments/20190111/c0d98c02/attachment-0003.png>