Radiofrequency Based Sensor Arrangement and a Method

• US 20070241762A1
• Filed: 12/16/2004
• Published: 10/18/2007
• Est. Priority Date: 12/18/2003
• Status: Active Grant

• Current Assignee: SMARTRAC Investment B.V. (Avery Dennison Corporation)
• Original Assignee: Upmkymmene Corporation
• Inventors: Seppa, Heikki, Varpula, Timo, Saari, Juha-Matti
• Granted Patent: US 7,714,593 B2
• Time in Patent Office: Days
• US Class Current: 324/655
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure
• CPC Class Codes: G08C 17/04 using magnetically coupled devices
• CPC Class Codes: G08C 17/06 using capacity coupling
• CPC Class Codes: Y10T 436/184 Only hydrogen sulfide

Abstract

A sensor arrangement for a sensor arrangement remotely readable by radio frequencies. The sensor arrangement includes an LC resonator that includes a capacitor and a coil, and a sensor element coupled to the LC resonator whose properties change as a function of a measurable quantity. A sensor element according to the invention does not form a direct galvanic contact with the LC resonator, rather the coupling is implemented capacitively or inductively.

Claims

1-22. -22. (canceled)

23. A sensor arrangement remotely readable by radio frequencies for determining desired quantities from sources, the arrangement comprising:

a LC resonator which comprises a capacitor and a coil, and

a sensor element coupled to the LC resonator, whose properties change as a function of a measurable quantity, the sensor element being coupled with the LC resonator without forming a direct galvanic contact.

24. The sensor arrangement according to claim 23, wherein the sensor element is cumulatively variable.

25. The sensor arrangement according to claim 23, wherein the sensor arrangement is suitable for use in monitoring deterioration of foodstuffs and medicinal substances.

26. The sensor arrangement according to claim 23, wherein the sensor element is adapted to couple capacitively to the LC circuit.

27. The sensor arrangement according to claim 26, wherein the capacitively couplable sensor element is disposed on top of the coil.

28. The sensor arrangement according to claim 26, wherein the capacitively couplable sensor element is disposed alone inside the package.

29. The sensor arrangement according to claim 23, wherein the sensor element is adapted to couple inductively to the LC resonator.

30. The sensor arrangement according to claim 29, wherein the inductively couplable sensor element is disposed in the middle of the coil.

31. The sensor arrangement according to claim 29, wherein the inductively couplable sensor element is disposed alone inside the package.

32. The sensor arrangement according to claim 31, wherein the inductively couplable sensor element is disposed inside an electrically conductive ring which is thicker than the sensor element.

33. The sensor arrangement according to claim 32, wherein the ring is circular, oval or polygonal in shape.

34. A sensor arrangement remotely readable by radio frequencies for determining desired quantities from sources, the arrangement comprising:

a LC resonator which comprises a capacitor and a coil, and

a sensor element coupled to the LC resonator, whose properties change as a function of a measurable quantity, the sensor element being coupled with the LC resonator capacitively.

35. The sensor arrangement according to claim 34, wherein the sensor element is cumulatively variable.

36. The sensor arrangement according to claim 34, wherein the sensor arrangement is suitable for use in monitoring deterioration of foodstuffs and medicinal substances.

37. The sensor arrangement according to claim 34, wherein the capacitively couplable sensor element is disposed on top of the coil.

38. The sensor arrangement according to claim 34, wherein the capacitively couplable sensor element is disposed alone inside the package.

39. A sensor arrangement remotely readable by radio frequencies for determining desired quantities from sources, the arrangement comprising:

a LC resonator which comprises a capacitor and a coil, and

a sensor element coupled to the LC resonator, whose properties change as a function of a measurable quantity, the sensor element being coupled with the LC resonator inductively.

40. The sensor arrangement according to claim 39, wherein the inductively couplable sensor element is disposed in the middle of the coil.

41. The sensor arrangement according to claim 39, wherein the inductively couplable sensor element is disposed alone inside the package.

42. The sensor arrangement according to claim 41, wherein the inductively couplable sensor element is disposed inside an electrically conductive ring which is thicker than the sensor element.

43. The sensor arrangement according to claim 42, wherein the ring is circular, oval or polygonal in shape.