Access control system having multiple sensing antenna coils
US8138884B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 2007 |
| Grant date | Mar 20, 2012 |
| Priority date | — |
| Expiry date | Nov 17, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C9/15
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An access control system has at least two antenna coils (12, 13 and 14, 15) arranged one behind the other at an entrance lane (4) and connected to a reading device (20), which with a capacitance (40, 41) form an oscillating circuit (30, 31). Here either the one oscillating circuit (30, 31) with the in entrance direction (5) first antenna coil (12, 13) or the other oscillating circuit with the second antenna coil (14, 15) is actuated by the reading device (20), in order to read out data for the purpose of access authorization from a transponder (22) which is carried by a user and has a transponder coil (24) coupleable with the antenna coils (12 to 15). The oscillating circuit (30, 31) not actuated by the reading device (20) is detuned or short-circuited.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.