Patent ID: 7773945

Claim:
A digital receiver circuit for a radio-frequency identification (RFID) tag reader comprising: an analog receiver circuit receiving an RFID tag response to a transmitted command, the analog receiver circuit producing an inphase RFID tag response signal and a quadrature RFID tag response signal from the RFID tag response and having a first analog switch for selecting one of the inphase and quadrature signals for digitizing, wherein the first analog switch receives the inphase and quadrature signals from a quadrature hybrid and provides the inphase and quadrature signals to a single receiver mixer; a single analog-to-digital converter connected via the first analog switch to the analog receiver circuit for digitizing the selected one of the inphase RFID tag response signal and the quadrature RFID tag response signal received from the analog receiver circuit; a digital signal processor for decoding digitized RFID tag response signals from the analog-to-digital converter, determining whether the digitized RFID tag response signals decode correctly and if the digitized RFID tag signals do not decode correctly with the analog switch in a first switch state, switching the analog switch from the first switch state to a second switch state; and a second analog switch for receiving the inphase and quadrature signals from the quadrature hybrid and controlling the provision of the signals via a transmitter to the receiver mixer.