On Sat, 2008-02-09 at 17:12 -0500, michael taylor wrote: > On Feb 9, 2008 4:58 PM, Bruce Griffiths <[EMAIL PROTECTED]> wrote: > > > > This indicates that the receiver can see SVN 23 (PRN 32) with no difficulty. > > However for a supposedly 8 channel receiver it sees 11 SVs?? > > I suspect that as long as less than 8 SV are being tracked (6 in your > sample), it only needs one channel to "not" track the other 5 SV. The > not tracked SV are not necessary being updated in a timely fashion so > a one or more unused channels could be used to cycle through all SVs / > PRNs from the almanac to look for new SV visibility and see if any of > the not tracked SV have become suitable to track. > > -Michael Taylor
Hi Michael, You only need to track one SV to get almanac (coarse ephemeris) data for the whole constellation. Almanac data gives you SV position within a few km, which is plenty good for visibility calculations. However to have current ephemeris data you would need to cycle an unused channel through the visible SV every so hour. -- Björn _______________________________________________ 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.
