RFID tags having improved read range
View Patent ↗The present invention provides a system and method for optimizing the performance of 13.56 MHz frequency RFID tags in conjunction with metal substrates. Briefly, a thickness exists for each type of RFID isolator material at which the performance of a 13.56 MHz RFID tag is optimal when used with metal. Varying from this optimal value, in either the positive or negative direction adversely affects read distance. A method of determining this optimal thickness is disclosed, as well as an RFID tag or a substrate being used in conjunction with a material of this thickness.
1. An identification system, adapted to transmit identifying information about an article via radio frequency, comprising:
an RFID tag, adapted to transmit said identifying information via radio frequency when energized; and a layer having first and second opposite surfaces, wherein said first surface is adapted to be in contact with said article, said second surface is in contact with said RFID tag; said layer having a thickness of less than 0.1 inches and a permeability of less than 10.
2. The system of claim 1 , wherein said identification system utilizes radio frequency at 13.56 MHz.
3. The system of claim 1 , wherein said layer comprises ferromagnetic material having a permeability greater than 1.
4. The system of claim 3 , wherein said material is selected from the group consisting of Nickel/Zinc Ferrite, Manganese/Zinc Ferrite, Carbonyl Iron, Carbonyl Iron+Magnetite, Iron Silicide and Iron/Nickel Alloy.
5. The system of claim 3 , wherein the optimal thickness of said layer of said ferromagnetic material, in mils, is equal to 240 divided by the permeability of said material.
6. The system of claim 1 , wherein said article comprises a cavity, and said layer and RFID tag are embedded in said cavity.
7. The system of claim 1 , wherein said article comprises metal.
8. The system of claim 1 , wherein said article comprises liquid.
9. An identification system, adapted to transmit identifying information about an article via radio frequency, comprising:
an RFID tag, adapted to transmit said identifying information via radio frequency when energized; and a layer having first and second opposite surfaces, wherein said first surface is adapted to be in contact with said article, said second surface is in contact with said RFID tag; said layer comprising ferromagnetic material having a permeability greater than 1 and less than 10 and a thickness, wherein said thickness, in mils, multiplied by said permeability is between about 170 and 450.
10. The system of claim 9 , wherein said ferromagnetic material is selected from the group consisting of Nickel/Zinc Ferrite, Manganese/Zinc Ferrite, Carbonyl Iron, Carbonyl Iron+Magnetite, Iron Suicide and Iron/Nickel Alloy.
11. The system of claim 9 , wherein said article comprises a cavity, and said layer and RFID tag are embedded in said cavity.
12. The system of claim 9 , wherein said identification system utilizes radio frequency at 13.56 MHz.
13. The system of claim 9 , wherein said article comprises metal.
14. The system of claim 9 , wherein said article comprises liquid.
15. An identification system, adapted to transmit identifying information about an article via radio frequency, comprising:
a substrate comprising an antenna and a silicon chip mounted thereon, adapted to transmit said identifying information via radio frequency when energized; and
a layer having first and second opposite surfaces, wherein said first surface is adapted to be in contact with said article, said second surface is in contact with said substrate; said layer having a thickness of less than 1 inches and a permeability of less than 10.
16. The system of 15 , wherein said identification system utilizes radio frequency at 13.56 MHz.
17. The system of claim 15 , wherein said layer comprises ferromagnetic material having a permeability greater than 1.
18. The system of claim 17 , wherein said material is selected from the group consisting of Nickel/Zinc Ferrite, Manganese/Zinc Ferrite, Carbonyl Iron, Carbonyl Iron+Magnetite, Iron Silicide and Iron/Nickel Alloy.
19. The system of claim 17 , wherein the optimal thickness of said layer of said ferromagnetic material, in mils, is equal to 240 divided by the permeability of said material.
20. The system of claim 15 , wherein said article comprises a cavity, and said layer and said substrate are embedded in said cavity.
21. The system of claim 15 , wherein said article comprises metal.
22. The system of claim 15 , wherein said article comprises liquid.
23. An identification system, adapted to transmit identifying information about an article via radio frequency, comprising:
a substrate comprising an antenna and a silicon chip mounted thereon, adapted to transmit said identifying information via radio frequency when energized; and
a layer having first and second opposite surfaces, wherein said first surface is adapted to be in contact with said article, said second surface is in contact with said substrate; said layer comprising ferromagnetic material having a permeability greater than 1 and less than 10 and a thickness, wherein said thickness, in mils, multiplied by said permeability is between about 170 and 450.
24. The system of claim 23 , wherein said identification system utilizes radio frequency at 13.56 MHz.
25. The system of claim 23 , wherein said ferromagnetic material is selected from the group consisting of Nickel/Zinc Ferrite, Manganese/Zinc Ferrite, Carbonyl Iron, Carbonyl Iron+Magnetite, Iron Silicide and Iron/Nickel Alloy.
26. The system of claim 23 , wherein said article comprises a cavity, and said layer and said substrate are embedded in said cavity.
27. The system of claim 23 , wherein said article comprises metal.
28. The system of claim 23 , wherein said article comprises liquid.