SPATIALLY SELECTIVE UHF NEAR FIELD MICROSTRIP COUPLER DEVICE AND RFID SYSTEMS USING DEVICE

• US 20120176224A1
• Filed: 03/16/2012
• Published: 07/12/2012
• Est. Priority Date: 08/29/2003
• Status: Active Grant

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: ZIH Corp. (Zebra Technologies Corporation)
• Inventors: Tsirline, Boris Y., Hohberger, Clive P., Gawelczyk, Robert, Donato, Daniel
• Granted Patent: US 8,351,959 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: G06K 1/12 otherwise than by punching
• CPC Class Codes: G06K 17/0025 the arrangement consisting of a wireless interrogation device in combination with a device for optically marking the record carrier
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications

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.

Claims

1. A method for communication with a transponder, comprising:

forming, with an RF communication signal, a near field concentration pattern in a transponder operating region larger than the transponder;

locating a transponder at a first position in the transponder operating region;

determining a first signal power level operationally effective to communicate with the transponder when located in the first position;

storing data associated with the first power level and the first position;

determining a second signal power level operationally effective to communicate with the transponder when located in a second position;

storing additional data associated with the second power level and the second position; and

operationally communicating with a series of transponders located in the first position and in the second position in the transponder operating region using the data and additional data to determine power levels and positions of the transponders in the transponder operating region.

2. The method of claim 1, further including storing type data identifying a type of the transponder.