Place Lab is software providing low-cost, easy-to-use user positioning for location-enhanced computing applications. Unlike existing positioning systems, Place Lab tries to provide positioning which works worldwide, both indoors and out, and is privacy observant. Place Lab clients can determine their location privately without constant interaction with a central service.

The Place Lab approach is to allow commodity hardware clients like notebooks, PDAs and cell phones to locate themselves by listening for radio beacons such as 802.11 access points, GSM cell phone towers, and fixed Bluetooth devices that already exist in the environment. These beacons all have unique or semi-unique IDs, for example, a MAC address. Clients compute their own location by hearing one or more IDs, looking up the associated beacons' positions in a locally cached map, and estimating their own position referenced to the beacons' positions.

This whitepaper introduces an open source toolkit that lets mobile devices determine their locations 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. According to the whitepaper, over four million of the required radio beacons have already been mapped.

Location awareness is an important capability for mobile computing. Yet inexpensive, pervasive positioning—a requirement for wide-scale adoption of location-aware computing—has been elusive. We demonstrate a radio beacon-based approach to location, called Place Lab, that can overcome the lack of ubiquity and high-cost found in existing location sensing approaches. Using Place Lab, commodity laptops, PDAs and cell phones estimate their position by listening for the cell IDs of fixed radio beacons, such as wireless access points, and referencing the beacons’ positions in a cached database.

Our coverage experiment confirmed the intuition that GPS, often thought of as a pervasive location technology, in fact lacks availability in people’s daily lives since people are frequently indoors or under cover, whereas 802.11 and GSM beacons are frequently available both indoors and out. This experiment was conducted by logging beacon availability using small recorders carried by people as they went about their daily routines.

Binary and source releases of Place Lab are available for many platforms along with sample radio traces at http://www.placelab.org/. >from *Place Lab: Device Positioning Using Radio Beacons in the Wild*

related context
> mologogo. location aware application: diy gps tracking. october 11, 2005
> keitai internet: territory machines. august 26, 2005
> geoserver: open access to geographic data. may 27, 2005
> datacities: sensity. may 13, 2005
> walking as knowing as making: a peripatetic investigation of place.april 15, 2005
> grafedia: hyperlinks for the urban landscape. february 18, 2005
> plan: pervasive and locative arts network. january 28, 2005
> urballon: an urban media space. october 8, 2004
> first international moblogging conference. location-specific content. june 30, 2003
> tormes: satellite navigation for blind people. june 11, 2003
> smart mobs: new uses of mobile. media linked to location. october 3, 2002
> blur building: inhabitable cloud. using tracking and location technologies. march 4, 2002
> digital angel, chip implant for humans. location and monitoring technology. october 30, 2000

imago
> the radio beacon emotional toolkit

sonic flow
> computing location [stream]
computing location [download]