Smart Phones with GPS vs Dedicated GPS Receivers

But do you still get Lat/Long output?


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A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

My cell phone, the HTC/Google G1, has 3 layered approaches to getting
positional data. The most accurate is from a GPS chip. As Sam
mentioned, the chip is designed to have the almanac and ephemeris
optionally loaded from data downloaded from a server somewhere (buzzword
A-GPS). That seems to be a bit of a crock, with a large number of
different A-GPS server standards. Until recently turning off the cell
xmitter didn't even slow down the GPS lock on time, indicating the A-GPS
wasn't even being utilized. That seems to now have changed, but lock-on
is still pathetically slow. I'm talking much slower than my two
SIRF-III gps's (2 minutes vs. 30-45 seconds).

The second positional method is to use a WIFI landscape check. It
appears that someone has a huge RF database of which WIFI SID's can be
seen from where and this is used to give what is usually a block-level
position. (They probably use the cell tower data to zero in on the
approximate location.)

The third layer is the cell tower location. Until 2 weeks ago it tended
to give a ~2-block accurate position. Something changed and it is now
showing a huge variation with several miles offset from my actual
position.

And yes, as I see it, CALEA in conjunction with E911 is going to cause a
serious security problem for folks as organized crime figures out how to
get that data (via bribes or break-ins into poorly secured cell phone
computers) and figures out when folks are on extended vacations etc.

-wolfgang
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Wolfgang S. Rupprecht Android 1.5 (Cupcake) and Fedora-11

That is annoying. With my Blackberry Bold and Google Maps, if I don't have
a cell connection, I can't "see" where I am. The GPSMap60 works a bit
better than that.

Google Maps is a lot easier to look things up on than the rocker-picker on
the Garmin. When I find the local Pizza joint, it's one button to make a
phone call. Google Local also uses my location automatically, even outside
of Google Maps.

I almost always have the phone, sometimes have the GPS.

Can't upload/download/save, or even expose waypoints on the BBerry.

Today, they are different gadgets, but no particualr reason that they need
to be.

I was just able to "refresh" my GPS location on a Blackberry Bold with no
cellular coverage. Opening Google Maps, it seems that I can fetch map
tiles via WiFi, so I can see where I am.

I have noticed that driving with the map displayed eats battery quickly,
but then it is also fetching new map tiles, so there's lots of cell data
moving.


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Clarence A Dold - Hidden Valley Lake, CA, USA GPS: 38.8,-122.5