ANTENNA CONSTRUCTION, FOR EXAMPLE FOR AN RFID TRANSPONDER SYSTEM

• US 20120206313A1
• Filed: 09/14/2010
• Published: 08/16/2012
• Est. Priority Date: 09/18/2009
• Status: Active Grant

• Current Assignee: Teknologian tutkimuskeskus VTT Oy
• Original Assignee: Teknologian tutkimuskeskus VTT Oy
• Inventors: Jaakkola, Kaarle
• Granted Patent: US 9,082,058 B2
• Time in Patent Office: Days
• US Class Current: 343/793
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07756 the connection being non-galvanic, e.g. capacitive
• CPC Class Codes: G06K 19/07771 the record carrier comprising means for minimising adverse effects on the data communication capability of the record carrier, e.g. minimising Eddy currents induced in a proximate metal or otherwise electromagnetically interfering object
• CPC Class Codes: G06K 19/07779 the inductive antenna being a coil
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/16 with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole H01Q9/44 takes precedence
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making
• CPC Class Codes: Y10T 29/49018 with other electrical component

Abstract

The invention relates to an antenna construction for an RFID chip for long ranges, which comprises a substrate, an antenna of conducting material supported by the substrate, and coupling means for coupling the antenna to a circuit. In accordance with the invention the antenna is a magnetic dipole, and the coupling means are formed by extensions of the antenna conductor.

Claims

1-19. -19. (canceled)

20. Antenna construction for a RFID chip for long ranges, which comprises

a substrate,

an antenna of conducting material supported by the substrate, and

coupling means for coupling the antenna to a circuit,

wherein

the antenna is a magnetic dipole, and

the coupling means are formed by extensions of the antenna conductor.

21. Antenna construction according to claim 20, wherein the coupling means are formed by overlapping extensions of the antenna conductor.

22. Antenna construction according to claim 20, wherein the coupling means are formed by parallel extensions of the antenna conductor.

23. Antenna construction according to claim 20, wherein the arrangement includes a microchip.

24. Antenna construction according to claim 20, wherein the coupling means are formed by overlapping extensions of the antenna conductor by electrode pairs of different but completely overlapping areas, whereby the smaller area defines the capacitance value of the coupling means.

25. Antenna construction according to claim 20, wherein the antenna and coupling means are formed by wrapping a conducting layer around a substrate.

26. Antenna construction according to claim 20, wherein the antenna and coupling means are formed by printed circuit board technology.

27. Antenna construction according to claim 26, wherein vias are used for forming the antenna.

28. Antenna construction according to claim 20, wherein conjugate impedance match between the microchip and the antenna is implemented by using a capacitive impedance transformer integrated in the antenna.

32. Method according to claim 20, wherein a microchip is connected to the coupling means.

34. Method according to claim 20, wherein forming the antenna and coupling means by wrapping a conducting layer around a substrate.

37. Method according to claim 20, wherein implementing conjugate impedance match between the microchip and the antenna by using a capacitive impedance transformer integrated in the antenna.

38. Use of the antenna defined in claim 20 on a platform such that the magnetic field caused by the antenna is arranged essentially parallel with the platform in order to minimize the influence of the platform material.

39. Antenna construction according to claim 21, wherein the arrangement includes a microchip.

29. Method for forming an antenna construction for a RFID chip for long ranges, which method includes steps for

forming an antenna of conducting material on a substrate, and

forming coupling means for coupling the antenna to a circuit,

wherein

forming the antenna as a magnetic dipole, and

forming the coupling means as extensions of the antenna conductor.

30. Method according to claim 29, wherein forming the coupling means by overlapping extensions of the antenna conductor .

31. Method according to claim 29, wherein forming the coupling means by parallel extensions of the antenna conductor.

33. Method according to claim 29, wherein forming the coupling means by overlapping extensions of the antenna conductor by electrode pairs of different but completely overlapping areas, whereby the smaller area defines the capacitance value of the coupling means.

35. Method according to claim 29, wherein forming the antenna and coupling means by printed circuit board technology.

36. Method according to claim 35, wherein using vias for forming the antenna.