Patent · US Expired

Resonant circuit detection measurement and deactivation system employing a numerically controlled oscillator

US6359562B2 · kind B2 · utility

44Cited by
9References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 16, 2001
Grant dateMar 19, 2002
Priority date
Expiry dateMar 16, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B13/242
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

An apparatus for deactivating a resonant circuit without physically contacting the resonant circuit. The EAS system includes a numerically controlled oscillator for generating an alternating electric signal, the frequency of the alternating electric signal varying in accordance with a numerical frequency control signal; a clock having a substantially fixed frequency connected to the numerically controlled oscillator; and a transmitting antenna connected to the numerically controlled oscillator for establishing an electromagnetic field within a deactivation zone. The frequency of the alternating electric signal is restricted to being an integer multiple of an integer sub-multiple of the clock frequency.

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