Out of somewhat “idle” curiosity, I was wondering what kind of AGREEMENT folks are seeing between 'recent' (last month-ish) OPUS Solutions, and the various “other” ONLINE alternatives?
I [naturally] ASSUME that everyone is “checking” the various alternative programs against OPUS [results] by simply submitting RINEX files to the alternative programs TODAY, that were submitted [say] last month to OPUS, and comparing the results of the alternative programs (SAME RINEX files) to the OPUS solutions.
Theoretically I would expect reasonably good AGREEMENT, but I am a little skeptical about some of the alternatives (e.g. antenna calibration models, “CORS” coordinate & velocity estimates, velocity estimates @ the remote station, not to mention some of the more esoteric models used by OPUS/PAGES_Lt).
I have about a week of static data that I collected in Nevada last week, and at this point I am simply 'sitting on it,' until such time as OPUS is back online. BUT if this drags out much longer, I am going to have to do some “roll-yer-own” processing. Not really a big deal, but OPUS has made me LAZY (even lazier than usual).
Loyal
My comparisons from a year or so ago are described here:
http://geodesyattamucc.pbworks.com/w/file/53012749/lab9_2012_summarySolutions.pdf
Remember that the IGS orbit products are products of the weighted average of solutions from different processing engines. The level of agreement among different processors is impressive.
Cheers,
DMM
Thanks a bunch!
Very impressive indeed.
Loyal
Howdy,
In addition to the more detailed summary in the previous post, a Spring 2013 numeric only comparison of the results from the free processing sites is shown here:
http://geodesyattamucc.pbworks.com/w/file/fetch/64369423/GPSsolutionsCompared_2013.pdf
The site: http://geodesyattamucc.pbworks.com includes links to all the sites used as well as extracts from each solution.
BTW, with respect to the repeatability of results among the various analysis centers submitting data to the IGS see the following document and note the graphic showing current agreement at the 2cm level. Document: http://igscb.jpl.nasa.gov/components/usage.html
Enjoy,
DMM
Great post! Thanks to all for the information.
Joe