Patent · US Expired

Pattern-comparing security tag detection system

US4663612A · kind A · utility

22Cited by
3References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 7, 1984
Grant dateMay 5, 1987
Priority date
Expiry dateSep 7, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B13/2445
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Security apparatus for detection of a security tag to be hidden in an article to be detected. The digitized waveshape of a tag signature signal preferably obtained by distortion of an oscillating magnetic field, (whereby the distortion signal being detected constitutes a signature signal) is compared with a stored digital representative of a signature signal, and an alarm enable signal is generating in the event of correlation a predetermined number of times in a predetermined time period. The stored signal is modified by the specific factors. The characteristics of the apparatus and of environmental factors. The result is a reliable detection apparatus with a very low false alarm rate.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.