Apparatus, method and use for screening the magnetic field of an RFID transponder

US8269688B2 · kind B2 · utility

Assignee

• Identive Systems GmbH · DE

Inventors

• Stefan Mieslinger · Kottgeisering, DE
• Michael Kober · Glonn, DE

Key dates

• Filing date: Jul 17, 2008
• Grant date: Sep 18, 2012
• Expiry date: Sep 26, 2029

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/49016
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

An apparatus for screening the magnetic field of a transponder is described, which apparatus comprises, in a first area section, at least one flat antenna structure which comprises conductor tracks for conducting current in a direction of current flow and has an application-specific extent, wherein the apparatus comprises a second area section or carrier to which strips of a highly permeable screening material are applied such that they are oriented with respect to one another in a predetermined manner, wherein the second area section is arranged parallel to the first area section. In order to effectively screen the magnetic field which is beamed in from the outside, for instance by a reader, and in order to effectively screen the magnetic field which is generated by the antenna structure of the transponder itself following excitation, and in order to reduce eddy current losses in a metal area arranged underneath, the highly permeable screening material has either anisotropic permeability, wherein increased permeability is provided in the direction of current flow, in particular in the direction of the conductor tracks of important sections of the antenna structure, or else provide…