Radio frequency identification inlay with improved readability
A radio-frequency identification (RFID) inlay is provided that is substantially isolated from the environment in proximity to one side of the device. A radio-frequency identification (RFID) inlay is provided including a two-port microchip having a first and a second port, a first antenna coupled to the first port of the two-port microchip, a ground-plane, a first high-impedance body disposed substantially parallel to the first antenna and between the first antenna and the ground-plane, the first high-impedance body insulated from the ground-plane. The RFID inlay further includes a second antenna coupled to the second port of the two-port microchip, and a second high-impedance body disposed substantially parallel to the second antenna and between the second antenna and the ground-plane, the second high-impedance body insulated from the ground-plane.
1. A radio-frequency identification (RFID) inlay comprising:
a microchip;
an antenna coupled to a port of the microchip;
a ground-plane disposed substantially parallel to the antenna;
a high-impedance body disposed substantially parallel to the antenna and between the antenna and the ground-plane; and
a continuous insulating layer disposed between the ground-plane and the high-impedance body to electrically insulate the high-impedance body from the ground-plane.
2. The RFID inlay of claim 1 , further comprising a laminate material disposed over an outer surface of the RFID inlay.
3. The RFID inlay of claim 2 , wherein the RFID inlay is an RFID card and the laminate material comprises a plastic material.
4. The RFID card of claim 3 , wherein the distance between the antenna and the ground-plane is one one-hundredth of the operational wavelength of the RFID inlay.
5. The RFID card of claim 3 having a thickness less than or equal to 0.76 millimeters.
6. The RFID card of claim 3 having a width less than or equal to 86 millimeters and a length less than or equal to 54 millimeters.
7. The RFID card of claim 3 having a rectangular or a circular shape.
8. The RFID inlay of claim 2 , wherein the RFID inlay is an RFID tag and the laminate material comprises a paper material.
9. The RFID tag of claim 8 , wherein the distance between the antenna and the ground-plane is one one-hundredth of the operational wavelength of the RFID inlay.
10. The RFID tag of claim 8 having a width less than or equal to 86 millimeters and a length less than or equal to 54 millimeters.
11. The RFID tag of claim 8 having a rectangular or a circular shape.
12. The RFID inlay claim 1 , wherein the high-impedance body comprises:
a capacitor and an inductor to produce a resonance at the operational frequency of the RFID inlay.
13. The RFID inlay of claim 1 , wherein the antenna is one of a C-shaped, or Z-shaped antenna.
14. A radio-frequency identification (RFID) inlay comprising:
a two-port microchip having a first and a second port;
a first antenna coupled to the first port of the two-port microchip;
a ground-plane;
a first high-impedance body disposed substantially parallel to the first antenna and between the first antenna and the ground-plane;
a second antenna coupled to the second port of the two-port microchip;
a second high-impedance body disposed substantially parallel to the second antenna and between the second antenna and the ground-plane, and;
a continuous insulating layer disposed between the ground-plane and the first high-impedance body to electrically insulate the first high-impedance body from the ground-plane.
15. The RFID inlay of claim 14 , further comprising a laminate material disposed over an outer surface.
16. The RFID inlay of claim 15 , wherein the RFID inlay is an RFID card and the laminate material comprises a plastic material.
17. The RFID card of claim 16 , wherein the distance between each of the antennas and the ground-plane is one one-hundredth of the operational wavelength of the RFID inlay.
18. The RFID card of claim 17 having a thickness is less than or equal to 0.76 millimeters.
19. The RFID card of claim 16 having a width less than or equal to 86 millimeters and a length less than or equal to 54 millimeters.
20. The RFID card of claim 16 having a rectangular or a circular shape.
21. The RFID inlay of claim 15 , wherein the RFID inlay is a RFID tag and the laminate material comprises a paper material.
22. The RFID tag of claim 21 , wherein the distance between each of the antennas and the ground-plane is one one-hundredth of the operational wavelength of the RFID inlay.
23. The RFID tag of claim 21 having a width less than or equal to 86 millimeters and a length less than or equal to 54 millimeters.
24. The RFID tag of claim 21 having a rectangular or a circular shape.
25. The RFID tag of claim 14 , wherein each of the high-impedance bodies comprises:
a capacitor and an inductor to produce a resonance at the operational frequency of the RFID inlay.
26. The RFID tag of claim 14 , wherein each of the antennas is one of a C-shaped or Z-shaped antenna.
27. The RFID tag of claim 14 , wherein the first and second antennas form an X-shape configuration centered about the two-port microchip.
28. The RFID tag of claim 14 , wherein the first antenna further comprises:
a first T-shaped element; and
a second T-shaped element coupled to the first T-shaped element at the two-port microchip,
and the second antenna further comprises:
a third T-shaped element; and
a fourth T-shaped element coupled to the third T-shaped element at the two-port microchip,
wherein the second antenna is rotated 90 degrees with respect to the first antenna about the two-port microchip.
29. The RFID inlay of claim 1 , wherein the high-impedance body comprises:
a plurality of conductive lands coupled by a plurality of conductive strips, the conductive lands coplanar to the conductive strips.
30. The RFID inlay of claim 29 , wherein the conductive lands and the conductive strips are segregated into at least six similarly patterned portions.
31. The RFID inlay of claim 14 , wherein at least one of the first high-impedance body or the second high-impedance body comprises:
a plurality of conductive lands coupled by a plurality of conductive strips, the conductive lands coplanar to the conductive strips.
32. The RFID inlay of claim 31 , wherein the conductive lands and the conductive strips are segregated into at least six similarly patterned portions.
33. The RFID inlay of claim 1 , wherein the insulating layer is a first insulating layer, further comprising:
a second insulating layer disposed between the antenna and the high-impendence body to electrically insulate the high-impedance body from the antenna, the first and second insulating layers forming an insulating body about the antenna and the high-impedance body and the ground-plane.
34. The RFID inlay of claim 29 , wherein the high-impedance body provides a resonance at the operational frequency of the RFID inlay, wherein the resonance is a function of an area of at least one of the conductive lands and a length of at least one of the conductive strips.
35. The RFID inlay of claim 31 , wherein the plurality of conductive lands and the plurality of conductive strips provide a resonance at the operational frequency of the RFID inlay, wherein the resonance is a function of an area of at least one of the conductive lands and a length of at least one of the conductive strips.
36. The RFID inlay of claim 14 , wherein the insulating layer is a first insulating layer, further comprising:
a second insulating layer disposed between the first antenna and the first high-impendence body to electrically insulate the first high-impedance body from the first antenna, the first and second insulating layers forming an insulating body about the first antenna and the first high-impedance body and the ground-plane.