DGPS is a specific service. WAAS is another specific service. They are
not the same thing although both provide diferential corrections.

Doug

"Jim Donohue" wrote in message
news:Yy7xd.379$iD.233@fed1read05...
Both are Differential Global Positioning System (DGPS). There are a large
number of ways to get the correcting signals. Nothing changes the fact
that they are the same technique implemented by two different
communication paths. You can also do differential by modulation of the
LORAN signal as is done in Europe. You can also use a local reference by
short wave. It is all differential.

WAAS is a little more sophisticated but the basics are the same.

Try it this way...if the differential signal from a USCG site was
forwarded to you by a satellite...say via Iridium...would it cease to be
DGPS and turn into WAAS? No I don't think so.

I also suggest that "Me" not comment until the question is understood.
"Bzzzt Wrong Answer"

Jim Donohue
"Me" wrote in message
...
In article paPwd.83$iD.50@fed1read05,
"Jim Donohue" wrote:

Actually WAAS is DGPS...Jim

Bzzzt Wrong answer. Would you like to try for what is behind Door #3?

WAAS is a SAT based Service, whereas DGPS is a MF Terrestrial based
Service. Two different things that try to correct the same GPS
accuracy.


Me