In article <[EMAIL PROTECTED]>, Eugen COCA <[EMAIL PROTECTED]> wrote: > Thomas Laus wrote:
> > It should happen twice a day, nearly 12 hours apart. Each GPS satellite > > is in an approx. 12 hour orbit. Your view of the constellation is the > > same about every 12 hours. True statement. > hours. But, in a fixed point on the Earth, a receiver do not see one > satellite for 12 hours ! And, the algorithm implemented in the receiver He never said that one satellite was seen for 12 hours. Or at least not in the quoted bit. > select the strongest signal from those received one time. So, the > receiver locks on several satellites over a day. A non-site surveyed receiver needs at least four satellite before it can even solve for time and should use all of those in view to reduce the uncertainty. A site surveyed receiver could use one satellite, but ought to use all of those in view. Signal strength is not a good measure of which is the best satellite. (As a pedantic point, for any one satellite there will be points on the earth that see it for a complete orbit.) _______________________________________________ questions mailing list questions@lists.ntp.isc.org https://lists.ntp.isc.org/mailman/listinfo/questions
