Hi Attila, > [ L1 / L2 timing differences ] > How do dual frequency receivers deal with that?
I've also been toying with the idea of an inexpensive dual- or tri-band GPS SDR, especially since there are now quite a few satellites emitting L2C, the civil L2 signal. (Though I'd still like to try my hand at the fancy L2 semicodeless schemes.) I think that manufacturers calibrate out the timing differences between channels (as well as group-delay variations within a channel). There must be some remaining error, though, e.g. over temperature, depending on the filter technology. ObTimeNuts: There's an interesting recent thesis on GPS for time and frequency metrology: http://www.ptb.de/cms/fileadmin/internet/fachabteilungen/abteilung_4/4.4_zeit_und_frequenz/pdf/Feldmann_2011_Dissertation.pdf Section 5.1.3 has a few words on exactly this channel-filter-delay issue. The author measures a coefficient of 20 ps per degree for a pair of receivers. Cheers, Peter _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
