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Peter Bennett
 
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On Sat, 16 Jul 2005 19:33:11 -0400, Larry wrote:

Peter Bennett wrote in
news
WAAS correction data is transmitted by two (Inmarsat?) geosynchronous
satellites, not by any of the normal GPS satellites.


I wonder if the reason the Canal is not using them is the canal is below
the footprint, probably pointed at the USA?? Geo-birds use very directive
antenna arrays to produce a useable signal from 40-50K miles away. They
usually have a fixed footprint that looks like an oval over the states with
these antennas. Maybe WAAS doesn't work in Panama so well because of
this??


The Panama Canal is likely too far outside the network of reference
stations used for creating the WAAS correction data for the data to be
considered reliable.


--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
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