Place Lab: Device Positioning Using Radio Beacons in the Wild

Anthony LaMarca, Yatin Chawathe, Sunny Consolvo, Jeffrey Hightower, Ian Smith, James Scott, Tim Sohn, James Howard, Jeff Hughes, Fred Potter, Jason Tabert, Pauline Powledge, Gaetano Borriello, and Bill Schilit


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. We

present experimental results showing that 802.11 and GSM beacons are

sufficiently pervasive in the greater Seattle area to achieve 20-30 meter median

accuracy with nearly 100% coverage measured by availability in people’s daily



Publication typeInproceedings
Published inProceedings of the 3rd International Conference on Pervasive Computing (Pervasive 2005)
PublisherSpringer Verlag
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