Hi Bruce: Is there a paper describing the method?
Have Fun, Brooke Clarke Have Fun, Brooke w/Java http://www.PRC68.com w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml http://www.precisionclock.com Dr Bruce Griffiths wrote: >Brooke Clarke wrote: > > >>Hi Didier: >> >>Many GPS receivers output carrier phase data but it's usually used in >>post processing to get survey grade position accuracy. Since the code >>phase position accuracy is larger than a wavelength the receiver does >>not know how many integer wavelengths to add. But because of satellite >>movement this can be figured out later. >> >>The exception is the "in development" carrier phase timing which as far >>as I know can only be done using the Ashtech Z12. >>The Motorola GPS receivers have carrier phase data available, but when >>the 8 channel models were current there was no way to use it without >>spending a small fortune. I think today there's a Motorola binary to >>RINEX converter. >> >>Have Fun, >> >>Brooke Clarke >> >> >> >> >Brooke > >It is not necessary to use a dual frequency phase tracking receiver to >significantly improve the disciplining of an OCXO over the performance >with a timng receiver. >A single frequency phase tracking receiver is more than adequate. >The largest problem is determining the ionospheric delay. >However this can be done by exploiting the difference between the phase >and group velocities in a dispersive medium (like the ionosphere). >Carrier phase measurements can be combined with code tracking >measurements to derive the difference between the phase and group delays. > >Commercial implementations of this technique are available from Quartzlock. >They use a single channel receiver, which switches between satellites. > >Disciplining an oscillator frequency is an easier problem than deriving >a geodetic solution, constant time offsets are of little consequence. > >Bruce > >_______________________________________________ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
