Wireless local area network (WLAN) method and system for presence detection and location finding
US7522049B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 2005 |
| Grant date | Apr 21, 2009 |
| Priority date | — |
| Expiry date | Apr 21, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W84/18
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A wireless local area network (WLAN) method and system for presence detection provide a low-cost and WLAN-compatible means for detecting the presence of an asset without requiring full location-finding support within a WLAN environment. The presence of a transmitter is detected by examining the signal strength of a presence signal. The presence signal is WLAN-compatible, but does not require association of the transmitter with the WLAN and does not require a response from the WLAN. The presence signal may be transmitted on multiple WLAN channels for presence detection by multiple WLAN APs. The presence signals transmissions may be periodic or may be stimulated by a stimulus from the WLAN or external device that may or may not be coupled to the WLAN. Location finding can also be performed in combination with the signal strength presence detection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.