Attila, > On Wed, 3 Jul 2013 08:29:02 -0400 > Bob Camp <li...@rtty.us> wrote: > >> There are two batches of GPS / WAAS sats up there: >> >> 1) The ones with numbers above 100 that are geosync and that only do >> WAAS >> >> 2) The ones with numbers <= 32 that do nav. These are not geosync. >> >> I believe the only ones with corrected / high stab clocks on board are >> those in the second group. The stuff in the first group aren't dedicated >> sats, just leased transponders on conventional multipurpose geosync >> birds. > > I don't know about WAAS, but AFAIK the EGNOS signals are generated on > ground using Cs references and retransmitted by the satelites using > a "bend pipe". Ie. the signals should be of time-nut quality even without > high accuracy frequency standards in the birds themselves. > > (Sorry, i'm not able to find where i read about that, so no references > today) > > Attila Kinali
WAAS is the US implementation of SBAS, EGNOS the European, MSAS the Japanese, GAGAN the Indian, etc... Here are some references. http://egnos-portal.gsa.europa.eu/library/technical-documents http://egnos-portal.gsa.europa.eu/sites/default/files/content/documents/egnos-user-guide_en.pdf You could also check the WAAS site at Stanford.edu. -- Björn _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.