| Re: Technical Specs of iPhone 3G posted |
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Group: alt.cellular.attws · Group Profile
Author: Todd AllcockTodd Allcock Date: Jun 16, 2008 06:40
At 16 Jun 2008 10:50:05 +0000 Larry wrote:
> But, how does it work? We know the position of the fixed towers. How
> does this software position the sellphone inside the Chrysler Building?
Lookup tables. At least with Navizon- the phone relays what WiFi APs and
cell towers are "visible" and Navizon's servers report back an approximate
position by supplying the coordinates of the last "real" GPS user that had
those same towers/APs visible.
> There must be some kind of pulse timing of some sort. TACAN has worked
> that way since the end of WW2....
You're making this waaaay too complicated. It's done over cellphone data-
send the "description" of the area to the server, and get the location back.
> But this isn't reality! The sellphone is on someone's hip on the 42nd
> floor of the Chrysler Building. Someone explain to me how you know where
> that sellphone is with all this wonderful "software" that defies all the
> physics of propagation. I'd love to hear SPECIFICALLY how it works.
>
> I still think it's bullshit.
It's mi
dly accurate. In Manhattan it generally got me pegged on the right block
to use navigation software or location services (i.e. the closest Dunkin'
Donuts) it won't get you within 30' like "real" GPS, but so what? It's for
plotting a route from where you are to Point B.
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