Cards and methods of reading the same
A card according to one embodiment includes an RFID circuit on or within a substrate and an antenna coupled to the RFID circuit, where the card is configured such that a signal associated with the card is capable of being read by at least one RF reader.
1. A device, comprising:
an RFID circuit on or within a substrate; and
an antenna coupled to the RFID circuit, where the antenna has a sheet resistivity of at least 1 Ω/sq.
2. The device of claim 1 , wherein the RFID circuit is included within a stack of objects for scanning by a reader.
3. The device of claim 1 , wherein a signal associated with the device is associated with a value of the device.
4. The device of claim 3 , wherein the device is configured such that the value of the device is capable of being determined by at least one RF reader.
5. The device of claim 1 , wherein the device is configured such that a signal associated with the device is capable of being read by at least one RF reader while the device is in a vicinity of a plurality of other devices.
6. The device of claim 1 , wherein the device is configured such that a signal associated with the device is capable of being read by at least one RF reader while the device is in a stack with a plurality of other devices.
7. The device of claim 1 , wherein the device is configured such that a signal associated with the device is capable of being read by at least one RF reader while the device is in a tray with a plurality of other devices.
8. The device of claim 1 , wherein the device is configured to: receive an interrogation signal from at least one RF reader; and send at least one response to the at least one RF reader in response to the interrogation signal.
9. The device of claim 8 , wherein at least one RF reader is capable of determining a value of the device from which the response is received.
10. The device of claim 1 , wherein the RFID circuit includes a passive RF device.
11. The device of claim 1 , wherein the device further comprises a battery coupled to the RFID circuit.
12. The device of claim 1 , wherein the device is configured such that a signal associated with the device is capable of being read by an RF reader associated with a table.
13. An RFID system, comprising:
at least one RF reader; and
a plurality of tags, each of the plurality of tags including:
an RFID circuit on or within a substrate; and
an antenna coupled to the RFID circuit,
wherein the RFID circuit has an input impedance greater than an impedance of the antenna;
wherein each of the plurality of tags are configured such that a signal associated with each of the tags is capable of being read by the at least one RF reader.
14. A tag, comprising:
an RFID circuit; and
an antenna coupled to the RFID circuit, the antenna having a sheet resistivity of at least 1 Ω/sq;
wherein the tag is configured such that a signal associated with the tag is capable of being read by at least one RF reader.
15. The gear of claim 14 , wherein a total impedance of each tag presented to a RF wave is greater than 10000.