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
In Proceedings of the 3rd International Conference on Pervasive Computing (Pervasive 2005)
Publisher Springer Verlag
All copyrights reserved by Springer 2005.