Wireless Positioning

An anonymous reader writes "This Intel-written whitepaper introduces a way to determine location with the aid of freely accessible, nearby radio sources, such as fixed Bluetooth devices, 802.11 access points, and GSM cell towers. Basically, the device reads the IDs of these local 'radio beacons' (each of which has a unique or semi-unique ID), looks up their positions in a locally-cached database, and performs a computation akin to triangulation. Intel created Place Lab in an effort to satisfy the emerging requirement for location-awareness within mobile devices such as smartphones, PDAs, and laptops, or even moving vehicles. According to the whitepaper, over four million of the required radio beacons have already been mapped."

Comments

Other Arts: E911, LORAN, Hybrid Triangulation

[ngr8]

Couple of observations:

Triangulation from fixed points does not require a time stamp, just directions.

Some other sources:
- Cellular Location Services (E911, drive by text ads...) some discussion at http://www.binspy.com/tech/lbsvs.html

- LORAN at http://www.loran.org/library.html

Arbitrary Precision
Having spent all of a minute to thing about this, wouldn't a multi-band/multi-protocol gizmo give the ability to find location in 2-space (if not 3-space) to an arbitrary level of precision? Example: the FM station signal locates the car in (x,y) with a circular error probable of 200 meters. AM station signals reduce it to a CEP of 10 meters (waves hands a lot now), and the radar leaks from airports reduce it to 2 meters....) Made up gedanken example, but it does seem feasible to me, gentle /. readers.