Patent · US Expired

RFID tags

US7205898B2 · kind B2 · utility

33Cited by
3References
72Claims
0Family size

Inventors

Key dates

Filing dateSep 30, 2005
Grant dateApr 17, 2007
Priority date
Expiry dateNov 30, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K19/07771
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A system and method for the use of ultra high frequency RFID tags in conjunction with metal substrates, as well as substrates used to contain liquid. Briefly, an RFID isolator comprised of a material with complex magnetic permeability, used either by itself, or in combination with dielectric isolator material, is interposed between the RFID tag and the substrate. Alternatively, a material possessing at least two distinct dielectric constants is interposed between the RFID tag and the substrate, such that there is a high dielectric constant at the interface with the substrate, and a low dielectric constant at the interface with the RFID tag. This material can be a single material having a dielectric constant gradient, or alternatively, two or more separate layers, each with a uniform but different dielectric constant, sandwiched together.

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