Global Patent Index - EP 0408573 B1

EP 0408573 B1 19960605 - DEVICE FOR THE IDENTIFICATION OF OBJECTS

Title (en)

DEVICE FOR THE IDENTIFICATION OF OBJECTS

Title (de)

ANORDNUNG ZUR IDENTIFIZIERUNG VON GEGENSTÄNDEN

Title (fr)

DISPOSITIF D'IDENTIFICATION D'OBJETS

Publication

EP 0408573 B1 19960605 (EN)

Application

EP 89902555 A 19890209

Priority

  • SE 8900051 W 19890209
  • SE 8800426 A 19880210

Abstract (en)

[origin: WO8907772A1] This invention relates to a method and apparatus for contactless identification of a label which incorporates passive resonators, with the aid of high-frequency magnetic fields. One significant feature of the inventive method is that large quantities of information of practical interest can be accommodated, despite the fact that the resonators can be given a Q-value which is so low as to enable the resonators to be given the form, e.g., of printed circuits mounted on plastic foil. The frequency stability requirement of the resonators is also low, which enables the labels to be produced very cheaply with the aid of suitable manufacturing techniques herefor, and also enables labels to be produced for one-time use only. The method is based on a high-frequency signal which is scanned over a broad frequency band and modulated at the same time, with appropriate detection, the modulation results in a response of narrower bandwidths than that obtained with earlier known methods, therewith enabling more resonators to be accommodated and to be separated within a given frequency range. The inventive apparatus with which the method is put into effect includes, inter alia, means for controlling the scan, modulation and amplification over the frequency band. One significant feature of the inventive apparatus resides in the provision of a coil arrangement which affords a comparatively large range while, at the same time, satisfying government regulations concerning maximum radiation powers.

IPC 1-7

G01S 13/82; G08B 13/24; H04B 1/59

IPC 8 full level

G08B 13/24 (2006.01)

CPC (source: EP)

G08B 13/2414 (2013.01)

Designated contracting state (EPC)

DE GB

DOCDB simple family (publication)

WO 8907772 A1 19890824; DE 68926619 D1 19960711; DE 68926619 T2 19961002; EP 0408573 A1 19910123; EP 0408573 B1 19960605; SE 501335 C2 19950116; SE 8800426 D0 19880210; SE 8800426 L 19890811

DOCDB simple family (application)

SE 8900051 W 19890209; DE 68926619 T 19890209; EP 89902555 A 19890209; SE 8800426 A 19880210