RFID tag, antenna, and printer system
View Patent ↗An RFID label with embedded tag is passed through an RFID antenna in a printer system, where the RFID antenna allows a roll of such labels to pass in close proximity to the antenna and still allow each individual RFID tag to be read and/or programmed. The RFID antenna module is formed with a transmission line coupled to an RF phase splitter, where in one embodiment, the transmission line is formed from two parallel conductive strips.
1. A printer system, comprising:
a roll of labels, wherein each label comprises a radio frequency identification (RFID) tag;
an RFID reader system comprising:
an RFID reader; and
an RFID antenna module coupled to the RFID reader, wherein the RFID antenna module comprises:
two electrical conductors, each having a first end and a second end;
a resistive element coupled to the second ends of the two conductors; and
a phase splitter coupled between the first ends of the two conductors and the RFID reader; and
a print head, wherein the RFID antenna is between the roll of labels and the print head.
2. The printer system of claim 1 , wherein the two electrical conductors form a transmission line.
3. The printer system of claim 2 , wherein the transmission line is an RF transmission line and the phase splitter is an RF signal phase splitter.
4. The printer system of claim 1 , wherein the resistive element has an approximate value that is equal to the characteristics impedance of the transmission line.
5. The printer system of claim 1 , further comprising a coaxial cable coupling the RFID reader to the RFID antenna.
6. The printer system of claim 1 , wherein the RFID tag is located along a lengthwise position in the label.
7. The printer system of claim 1 , wherein the conductors are orientated parallel to a path of the roll of labels across the RFID antenna module.
8. The printer system of claim 7 , wherein the length of the conductors can be changed to control longitudinal write and read distances of the RFID tag.
9. The printer system of claim 1 , wherein the two conductors are approximately 180 electrical degrees out of phase with respect to each other.
10. The printer system of claim 1 , wherein the RFID antenna further comprises a printed circuit board, wherein the two conductors are secured above the printed circuit board.
11. The printer system of claim 10 , wherein the phase splitter is further secured to the printed circuit board.
12. The printer system of claim 10 , further comprising a dielectric layer separating the printed circuit board from the two conductors.
13. The printer system of claim 1 , wherein the RFID antenna further comprises a printed circuit board and a dielectric layer, wherein the dielectric layer is between the two conductors and the printed circuit board.
14. The printer system of claim 13 , wherein the two electrical conductors are encapsulated in a second dielectric layer.
15. An RFID antenna module for use in a printer system for printing RFID labels, the system including an RFID reader coupled to the RFID antenna module and RFID labels passing in close proximity to the RFID antenna module, the RFID antenna module comprising:
a dielectric layer;
a transmission line located above a top surface of the dielectric layer, wherein the transmission line has a first and a second end;
a resistor coupled to the first end of the transmission line; and
a phase splitter coupled to the second end of the transmission line.
16. The RFID antenna module of claim 15 , wherein the transmission line is formed from two parallel conductors.
17. The RFID antenna module of claim 15 , further comprising a coaxial cable coupled to the phase splitter and the RFID reader.
18. The RFID antenna module of claim 15 , wherein the transmission line comprises a conductive material.
19. The RFID antenna module of claim 15 , further comprising a second dielectric layer encapsulating the transmission line.
20. The RFID antenna module of claim 15 , further comprising a printed circuit board, wherein the dielectric layer is between the printed circuit board and the transmission line.
21. The RFID antenna module of claim 20 , further comprising a second dielectric layer encapsulating the two electrical conductors of the transmission line.
22. The RFID antenna module of claim 15 , wherein the transmission line, resistor, and phase splitter are contained in a snap-in-place module.
23. The RFID antenna module of claim 15 , wherein the transmission line is operational over multitude operating frequencies of the of RFID labels.