Using a derived table of signal strength data to locate and track a user in a wireless network
US6839560B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2000 |
| Grant date | Jan 4, 2005 |
| Priority date | — |
| Expiry date | Feb 25, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W88/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for locating a user in a wireless network is disclosed. A mobile computer seeking to determine its location within a building detects the signal strength of one or more wireless base stations placed at known locations throughout the building. The mobile computer uses this measured signal strength to determine its location via a signal-strength-to-location table look-up. A table of known locations within the building and the base station signal strength at those locations is searched to find the most similar stored signal strength to the signal strength detected. The location corresponding to the most similar stored signal strength is determined to be the current location of the mobile computer. Alternatively, a number of signal strengths from the table can be used and the corresponding locations can be spatially averaged to determine the location of the mobile computer. The table can be derived empirically, by placing a mobile computer at the known locations and detecting the signal strength of the wireless base stations at those locations, or the table can be derived mathematically by taking into account a reference signal strength, the distance between the reference poin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.