[IGSMAIL-8279] A new keyword in Bias-SINEX for antenna phase center corrections on geometry-free biases

[Jianghui Geng]

Dear colleagues,

As stated in IGSMAIL-8113, the frequency-specific antenna phase centers
(APCs) resulted in inconsistencies among the geometry-free biases such as
differential code biases (DCBs) and wide-lane (aka Melbourne-Wübbena)
biases. All IGS Analysis Centers have been required to apply the antenna
phase center offset corrections to those geometry-free combination
observables during the transition to ITRF2020. Similarly, users of IGS
products will need to adopt this new convention as well to ensure
consistency and achieve the best performance in ambiguity resolution.

As the IGS has decided to transition to ITRF2020 and authorize the
igs20.atx at the end of this November, users of IGS products need to be
reminded of the following change on the Bias-SINEX format:

A new keyword "APC_MODEL" will be added to the section “BIAS/DESCRIPTION”
in the format of "APC_MODEL igs20_WWWW.atx" when APCs are considered for
geometry-free biases.

Best regards,
-- 

Jianghui GENG

Professor in GNSS Geodesy

GNSS Research Center, Wuhan University

Office: +86 (0)27 68778955

Homepage: http://pride.whu.edu.cn
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.igs.org/pipermail/igsmail/attachments/20221121/63f26cee/attachment.htm>