RFID tags with B-field focusing
AssigneeFortiss, LLC
InventorsForrest S. Seitz, Tyler J. Seitz, Joshua K. Hoyt
Life of this patent
Estimating the term…
Abstract
A radio-frequency identification (RFID) tag includes circuit elements that result in a resonant frequency that differs from the excitation frequency of an RFID reader. The RFID tag, when stacked with other similar RFID tags, channels the magnetic flux density field (B-field) through the stack to power each of the tags in the stack. As a result, the B-Field is collimated in a manner that increases the sensitivity (read range) in one dimension (up a stack of chips) while simultaneously limiting the sensitivity in the two lateral dimensions, thereby providing precise spatial resolution of each tag as to its location on a gaming table.
Claims20
A radio-frequency identification (RFID) tag, comprising:
- RFID tag electronics;
- and
- an antenna coupled to the RFID electronics,
- wherein the RFID tag has a resonant frequency, wherein the resonant frequency of the RFID tag is higher than an excitation frequency of a transmission generated by an RFID reader,
- wherein the RFID tag is one of a plurality of RFID tags in proximity in a grouping, wherein the grouping of RFID tags shapes a magnetic flux density field of the transmission generated by the RFID reader through the grouping of RFID tags, wherein the grouping of RFID tags has a resonant frequency that is lower than the resonant frequency of each of the plurality of RFID tags considered individually due to resonant coupling, and wherein the transmission generated by the RFID reader powers the RFID tag electronics via the resonant coupling.
A system for determining locations of objects in a gaming environment, the system comprising:
- a plurality of radio-frequency identification (RFID) antennas arranged at a plurality of locations on a gaming table;
- one or more RFID readers coupled to the plurality of RFID antennas;
- and
- a plurality of RFID tags, wherein a given RFID tag of the plurality of RFID tags comprises:
- RFID tag electronics;
- and
- an antenna coupled to the RFID electronics,
- wherein the given RFID tag has a resonant frequency, wherein the resonant frequency of the given RFID tag is higher than an excitation frequency of a transmission generated by the one or more RFID readers,
- wherein the plurality of RFID tags are in proximity in a grouping, wherein the grouping of RFID tags shapes a magnetic flux density field of the transmission generated by the one or more RFID readers through the grouping of RFID tags, wherein the grouping of RFID tags has a resonant frequency that is lower than the resonant frequency of each of the plurality of RFID tags considered individually due to resonant coupling, and wherein the transmission generated by the one or more RFID readers powers the RFID tag electronics via the resonant coupling.
Dependencies are inferred from the claim text.