Systems, methods and associated RFID antennas for processing a plurality of transponders
View Patent ↗An RFID system for selectively communicating with a targeted transponder from among a group of multiple adjacent transponders is provided. The RFID system may include a transponder conveyance system adapted to transport at least one targeted transponder from a group of multiple adjacent transponders through a transponder encoding area along a feeding direction and an antenna having a resonant inductor and a ferrite material, wherein the ferrite material at least partially covers the resonant inductor and defines an exposed portion of the resonant inductor. In one antenna-transponder alignment, the exposed portion extends substantially parallel to the feeding direction.
1. A system configured to communicate with a targeted transponder disposed between an upstream transponder and a downstream transponder, wherein the upstream transponder, the targeted transponder, and the downstream transponder are disposed on a web and movable along a feed path in a feed direction through a communication area, the system comprising:
a transponder conveyance system configured to transport the downstream transponder, the targeted transponder, and the upstream transponder via the web along the feed path to an interrogation position in which the targeted transponder and an antenna are substantially aligned lengthwise and the targeted transponder is within the communication area; and
the antenna configured to generate a magnetic field that is concentrated at the communication area such that, in the interrogation position, at least a portion of the targeted transponder collects magnetic flux of the magnetic field capable of activating the targeted transponder and neither the upstream transponder nor the downstream transponder collects magnetic flux of the magnetic field capable of activation, wherein:
the antenna defines:
an antenna length extending in the feed direction; and
an antenna plane extending along the antenna length;
the targeted transponder defines:
a transponder plane that is parallel to the web;
the antenna plane and the transponder plane are the same plane when the targeted transponder is positioned in the interrogation position.
2. The system of claim 1 , wherein the antenna includes a resonant inductor and a shielding element that at least partially encloses the resonant inductor thereby defining an exposed portion of the resonant inductor and an enclosed portion of the resonant inductor, and wherein the exposed portion of the resonant inductor extends substantially parallel to the feed path.
3. The system of claim 2 , wherein the resonant inductor includes a spiral coil on a printed circuit board.
4. The system of claim 2 , wherein the shielding element includes a ferrite material.
5. The system of claim 1 further comprising:
a housing; and
a printhead configured to print indicia on media units including transponders.
6. The system of claim 5 , wherein the printhead is positioned proximate to a media exit of the housing where the media units exit the housing.
7. The system of claim 6 further comprising a platen roller adjacent the media exit.
8. The system of claim 6 , wherein the communication area overlaps with the interrogation position and is less than a length of a media unit from the media exit.
9. The system of claim 8 , wherein the printhead is configured to print indicia on the media units within the communication area.
10. The system of claim 1 , wherein the antenna length defines a longest dimension of a coupling portion of the antenna.
11. The method of claim 1 , wherein the antenna length defines a longest dimension of a coupling portion of the antenna.
12. A method of encoding a targeted transponder disposed on a web between an upstream transponder and a downstream transponder, comprising:
moving the upstream transponder, the targeted transponder, and the downstream transponder via the web along a feed path in a feed direction through a communication area, where the targeted transponder defines a first plane when the targeted transponder is positioned in the communication area, the first plane being parallel to the web;
generating a magnetic field from an antenna that is concentrated at the communication area, wherein the antenna defines a second plane extending along an antenna length, the second plane the same as the first plane when the targeted transponder positioned in the communication area, the antenna length extending in the feed direction; and
transporting the downstream transponder, the targeted transponder, and the upstream transponder along the feed path to an interrogation position in which the targeted transponder and the antenna are substantially aligned lengthwise and the targeted transponder is within the communication area; and
activating the targeted transponder, when the targeted transponder is in the interrogation position, by causing at least a portion of the targeted transponder to collect magnetic flux of the magnetic field capable of activating the targeted transponder and neither the upstream transponder nor the downstream transponder collects magnetic flux of the magnetic field capable of activation.
13. The method of claim 12 , wherein generating the magnetic field further comprises generating the magnetic field from the antenna that includes a resonant inductor and a shielding element that at least partially encloses the resonant inductor thereby defining an exposed portion of the resonant inductor and an enclosed portion of the resonant inductor, and wherein the exposed portion of the resonant inductor extends substantially parallel to the feed path.
14. The method of claim 12 further comprising printing indicia on media units including transponders.
15. The method of claim 14 , wherein the printing is performed by a printhead positioned proximate to a media exit of a housing where the media units exit the housing.
16. The method of claim 15 , wherein activating the targeted transponder occurs less than a length of a media unit from the media exit.
17. The method of claim 14 , wherein the printing occurs within the communication area.