I took a quick look at the usno pdf mentioned here and it seems to cover this subject pretty thoroughly:
http://www.kurzweilai.net/faster-than-light-neutrino-puzzle-claimed-solved-by-special-relativityFaster-than-light neutrino puzzle claimed solved by special relativity
October 14, 2011 by Editor
The relativistic motion of clocks on board GPS satellites exactly accounts for the superluminal effect in the OPERA experiment, says physicist Ronald van Elburg at the University of Groningen in the Netherlands, The Physics arXiv Blog reports.
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October 14, 2011
by gvseostud
My fear is that this paper will only add to the confusion regarding GPS time. Any complete treatment of GPS time should discuss how a ground receiver is using time, in accordance with ICD-GPS-200:
http://www.navcen.uscg.gov/pubs/gps/icd200/ICD200Cw1234.pdfThis has been debated already in literature here:
http://tycho.usno.navy.mil/ptti/1996/Vol%2028_16.pdfThe conclusion was that relativistic corrections were being accounted for by OCS Kalman filtering to within 2.5mm, for time of flight corrections to within 8 pS.
I am not saying there are not systematic errors in the propagation of GPS time, but I am saying that van Elburg’s paper is not a good treatment of them.
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October 14, 2011
by gvseostud
Note especially this quote from the second linked reference:
“…this error would be incurred only if the station clocks were independent of the GPS satellite clocks, each MS keeping its own time. That’s not the way the OCS works. Station time is estimated in the Kalman filter together with the SV clocks, and each MS clock is effectively being updated continuously by the satellites. The station clock is used only to bridge the gap in time between measurements; but since several satellites are always in view, these measurements are virtually instantaneous, except for the different signal propagation times from different satellites. These times are about 0.1 sec, and, multiplying by 7, once more we derive an error of about 2.5 millimeters.”
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