| Steve & Susan 2005-05-23, 9:01 am |
| On Mon, 23 May 2005 00:42:40 GMT, CharlesH <hoch@exemplary.invalid>
wrote:
>At www.snaptrack.com, they make fairly aggressive claims about how their
>aGPS system will work in severe (for GPS) conditions (indoors /
>basements / urban canyons). Do you feel that these claims are over-stated?
Interesting idea. It looks like the system eliminates the time it
takes to build an almanac, collects and sends differential correction
via overhead signaling and is supplemented by TDOA (?) information
through the network. It's nifty, but I'm not sure if it will work in a
building using GPS or will more likely use the GPS to establish some
degree of precision tolerance and then use the TDOA (or similar) to
fill in when there is some impediment to getting a signal on the
receiver.
I'm not sure whether I want to be consistently blurping position
requests, either. I mean, sure, you are constantly registering into
the system as you walk or drive around, but think of it - a system
that can use GIS to calculate exactly where its users are and where
they are not... wasn't that in one of those Schwarzeneggar movies,
where the advertisements knew where people were and hawked them
everywhere they went?
Steve
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