Patent ID: 8013715

Claim:
A method for canceling self-jammer signals in a radio frequency identification (RFID) system, comprising: generating a first radio-frequency signal comprising a signal generated at a local oscillator of an RFID reader; transmitting the first radio-frequency signal; receiving a second radio-frequency signal comprising one or more self-jammer signals, the one or more self-jammer signals comprising the transmitted signal; detecting characteristics of the one or more self-jammer signals; generating a self-jammer cancellation signal comprising the signal generated at the local oscillator and based, at least in part, on the detected characteristics of the one or more self-jammer signals; canceling the one or more self-jammer signals in a cancellation loop, wherein canceling the one or more self-jammer signals comprises out-phasing the self-jammer signal with the self-jammer cancellation signal; and shifting a phase of a transmit signal based at least in part on characteristics detected in the detection circuit.