Antenna for Communication with a Multitude of Transponders

• US 20080169985A1
• Filed: 07/13/2005
• Published: 07/17/2008
• Est. Priority Date: 07/16/2004
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Hubmer, Paul, Schwar, Christian
• Granted Patent: US 7,570,168 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: H01Q 1/22 by structural association with other equipment or articles

Abstract

An antenna (1) for communication with a multitude of transponder % (6a . . . 6c) is provided, the antenna (1) having an antenna conductor (2) which completely encloses at least one read/write region (4c) intended for a transponder (6c) individually and/or, when a multitude of read/write regions (4a, 4b) are arranged within a continuous inner region (3) enclosed by the antenna conductor (2), the inner region (3) has constrictions (5a) between the read/write regions (4a, 4b) so that the antenna conductor (2) largely encloses these read/write regions (4a, 4b) individually. The electromagnetic field radiated by the antenna (1) is thereby concentrated on the read/write regions (4a . . . 4c).

Claims

1. Antenna for communication with a multitude of transponders the antenna having an antenna conductor which encloses a multitude of read/write regions intended for transponders wherein

the antenna conductor completely encloses at least two read/write regions individually, or wherein

the antenna conductor encloses a continuous inner region which has constrictions between a multitude of read/write regions contained in it, so that the antenna conductor largely encloses at least two read/write regions individually, or wherein

the antenna conductor completely encloses at least one read/write region individually and also encloses a continuous inner region which has constrictions between a multitude of read/write regions contained in it, so that the antenna conductor largely encloses at least two read/write regions individually.

2. An antenna as claimed in claim 1, characterized in that the enveloping angle of the antenna conductor is more than 360 degrees in the case of a fully enclosed read/write region.

3. An antenna as claimed in claim 2, characterized in that the antenna conductor encircles adjacent read/write regions in opposite directional senses.

4. An antenna as claimed in claim 1, characterized in that in the case of a multitude of read/write regions within a continuous inner region the ratio of the maximum circle circumscribed for a read/write region in the inner region to the minimum circle circumscribed for a constriction in the inner region is at least 1.5.

5. An antenna as claimed in claim 4, characterized in that center spacing of two maximum circles which are circumscribed for adjacent read/write regions in the inner region and which have a minimum spacing from each other, corresponds to at least 1.5 times the sum of their radii.

6. An antenna as claimed in claim 1, characterized in that the read/write regions respectively lie in mutually parallel planes or in a single plane and the antenna conductor is likewise laid out in the respective plane of a read/write region.

7. An antenna as claimed in claim 1, characterized in that the read/write regions lie on a geometrical surface and the antenna conductor is likewise laid out on this surface.

8. An antenna as claimed in claim 1, characterized in that a read/write region is configured so that an antenna of a transponder can be arranged fully within this read/write region.

9. A communication station for communication with a multitude of transponders comprising:

at least one antenna as claimed in claim 1,

a supply device for supplying the antenna with electric power, and

an evaluation unit which is coupled to the antenna.

10. Use of an antenna as claimed in claim 1 and/or a communication station in a display shelf, an item of practical use or a vending machine.