Variable-q antenna coil circuit for rfid applications
AssigneeAvid Identification Systems, Inc.
InventorsGui-Yang Lu, Peter Troesch
Life of this patent
Estimating the term…
Abstract
A passive radio frequency identification (RFID) reader is configured to dynamically vary the Q factor of its resonant antenna coil circuit in order to optimize its performance under different conditions. This RFID reader suitably provides optimal performance for both transponder reading and transponder writing operations, rather than being designed for optimal performance for only one operation or the other, or some fixed compromise between them.
Claims21
1-16. (canceled)
A method for communicating with a radio frequency identification (RFID) transponder using a RFID circuit comprising a resonant antenna coil circuit having a Q factor, the method comprising:
- during a read-only mode of an RFID circuit, receiving at the RFID circuit a signal from the transponder while operating the resonant antenna coil circuit at a first value for the Q factor;
- varying the Q factor from the first value to a second value lower than the first value;
- and
- during a read/write mode of the RFID circuit, receiving at the RFID circuit a signal from the transponder and transmitting from the RFID circuit a signal to the transponder while operating the resonant antenna coil circuit at the second value for the Q factor.
A computer readable medium containing program instructions for communicating with a radio frequency identification (RFID) transponder using a RFID circuit comprising a resonant antenna coil circuit having a Q factor, wherein execution of the program instructions by one or more processors of a computer system causes the one or more processors to carry out the steps of:
- during a read-only mode of an RFID circuit, receiving at the RFID circuit a signal from the transponder while operating the resonant antenna coil circuit at a first value for the Q factor;
- varying the Q factor from the first value to a second value lower than the first value;
- and
- during a read/write mode of the RFID circuit, receiving at the RFID circuit a signal from the transponder and transmitting from the RFID circuit a signal to the transponder while operating the resonant antenna coil circuit at the second value for the Q factor.
Dependencies are inferred from the claim text.