US 7,398,054 B2 · Spatially selective UHF near field microstrip coupler device and RFID systems using device

Abstract

A system having a UHF RFID transceiver is adapted to communicate exclusively with a single electro-magnetically coupled transponder located in a predetermined confined transponder operating region. The system includes a near field coupling device comprising a plurality of lines connected in parallel with an unmatched load. The near field coupling device may be formed, for example on a printed circuit board with a plurality of electrically interconnected traces and a ground plane. The system establishes, at predetermined transceiver power levels, a mutual electro-magnetic coupling which is selective exclusively for a single transponder located in a defined transponder operating region. Also included are methods for selective communication with the transponder in an apparatus such as a printer-encoder.

Claims12

Dependent claims

A near field coupling device, comprising:

a plurality of lines electrically interconnected in parallel to form a one half wavelength transmission line or multiple thereof;
a ground plane spaced away from the plurality of lines;
and
a terminating resistor coupled to the plurality of lines, the terminating resistor selected not to match a characteristic impedance of the plurality of lines such that the near coupling device operates as a one-half wavelength unmatched transmission line.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

10/604,996Filed 29 Aug 2003

Published

US 2005/0045723 A13 Mar 2005

Granted

8 Jul 2008

Term ends

Not estimatedThe source records don’t support an estimate.

Classification8 codes

G06K 7/10366
Sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves: the interrogation device being adapted for…
G06K 1/12
Methods or arrangements for marking the record carrier in digital fashion: otherwise than by punching
G06K 7/0008
Methods or arrangements for sensing record carriers, e.g. for reading patterns: general problems related to the reading of electronic memory…
G06K 7/10079
Resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers.: the collision being…

Spatially selective UHF near field microstrip coupler device and RFID systems using device

Life of this patent

Spatially selective UHF near field microstrip coupler device and RFID systems using device

Life of this patent

Abstract

Claims12