Posts tagged with "ionosphere"

13. October 2018
At the ION GNSS+ 2018 conference, I presented a paper based on a joint effort between NRCan and Swift Navigation on network modelling considerations for wide-area ionospheric corrections. Both organizations had similar questions regarding this topic: what is the recommended station density to reach cm-level ionospheric corrections? And is it better to use a 3D model or a per-satellite model? This blog post summarizes our findings.
14. August 2017
Obtaining mm-level positioning accuracies with GNSS requires modeling of all error sources such as higher-order ionospheric effects. As a part of an IAG working group, I collaborated with European colleagues to investigate how this error source could be estimated as a part of the PPP filter. The results were published last week in GPS Solutions (Banville et al. 2017).
27. January 2017
For almost two years now, I have been extracting precise slant ionospheric delays from over 200 permanent GNSS stations in Canada using PPP-AR. Since there is no official data format for storing GNSS-derived slant ionospheric delays, I have developed by trial and error a format that is at least suitable for my own purposes. Since precise ionospheric delays are key to fast PPP convergence, we can certainly foresee a need for exchanging this kind of information in the future.
29. July 2016
It is well known that the 'leveling' process, in which carrier phases are fitting to code observations, is a source of error in the determination slant total electron content (STEC). These leveling errors can be greatly attenuated when using carrier-phase ambiguities obtained from PPP as leveling information. In this post, I show how leveling errors can also impact VTEC and, potentially, DCB estimates.