System and method for detecting persons or objects in definite areas provided each with at least an entrance
US7325723B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 14, 2002 |
| Grant date | Feb 5, 2008 |
| Priority date | — |
| Expiry date | May 14, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C9/00
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A system and a method are described for detection of individuals (8) or objects in a plurality of delimited spaces (10), each having at least one entrance (6). The detection system comprises LF transmission means (4, 4*, 5, 5*) located at the entrance, for transmitting a LF electromagnetic signal, HF transmission-reception means (12, 13) for transmitting-receiving a HF electromagnetic signal (C, ACK), cards or portable electronic units (36) equipping each individual or object, for receiving the LF signal and for transmitting and receiving the HF signal, and a central processing unit (20) for recording data relating to the entry and exit of the portable electronic units. The system can operate according to at least two distinct modes of operation and the LF signal comprises selection information (SELECT) indicating which of the two modes of operation should be used by the electronic units during their passage through the entrance. The system is preferably configured to pass, at least temporarily, in one of the said delimited spaces, from one mode of operation to the other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.