Patent · US Expired

Dual resonant antenna circuit for RF tags

US5317330A · kind A · utility

33Cited by
13References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 7, 1992
Grant dateMay 31, 1994
Priority date
Expiry dateOct 7, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K19/0723
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A two-way communication system is provided having a stationary device and a portable passive device. The portable passive device has circuitry for storing and transmitting coded information. The stationary member transmits a signal at a first frequency via magnetic field and the portable passive device transmits coded information stored on circuitry provided therein at a second frequency also via a magnetic field. An antenna circuit is provided in the portable passive device having a parallel resonant circuit and a series resonant circuit. The parallel resonant circuit derives operating power from the signal at a first frequency for use in the circuitry provided in the portable passive device. The series resonant circuit transmits coded information at a second frequency.

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