Apparatus for the surveillance of an electronic security element in an interrogation zone
US5969611A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 20, 1997 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | Nov 20, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2482
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The present invention relates to an apparatus for the surveillance of an electronic security element in an interrogation zone. The essential elements are a transmitting device, a receiving device and a computing/control unit. The transmitting device emits at least one interrogation signal into the interrogation zone. This signal causes the security element to emit a characteristic signal. The receiving device receives the characteristic signal and generates a signal which is an indication of the characteristic signal. The computing/control unit evaluates the signals received from the receiving device and produces an alarm when the presence of the security element is established. The evaluation comprises detecting spikes from the signals received from the receiving device, creating a corresponding signal shape from the spikes in a self-learning process, and removing the determined spikes from the signals received from the receiving device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.