[aprssig] RE: indoor tracking.

KC2MMi kc2mmi at verizon.net
Wed Jun 1 14:11:09 EDT 2005


Chris-
  The cell phone companies are purely cost-driven. Whatever costs the least
and meets the laws, is what they deploy. So complete GPS chips are rare in
cell phones. Several (most?) of the carriers are going to a software-only
solution that can be implemented on the towers, which uses timing delays to
triangulate the phone's position, and then software in the phone to display
this--at a cost to the cell phone user. (Never give away what you can sell!)
  In terms of using your cell phone for "real" WAAS-GPS acccuracy, don't
expect them to make that available unless you are charged per use, or buy an
expensive phone. Market economics.

 Bob-
Why ask the ARRL to reinvent the wheel? You can get two or three free RFID
fobs now from Exxon-Mobil, they will send two speedpass fobs (pencil width,
less than an inch long) to anyone who applies, at no charge. Now, your
challenge as a ham operator is to hack the fob, and find out how to build
RFID stations that can read it!<G> They'll also give you a larger
"windshield mount" version, still free, that is more powerful. Plenty of fun
to be had for free--and it also makes it easier for me to buy gas. (There
are a couple of very competitive Mobil stations around me, I'm not paying
"more" in any way for this.)
 I'd love to know how to tell my car to read the Speedpass (like the
Corvette and now the Lexus) so it could just recognize me and disarm!





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