Method and apparatus for improving reception of an RFID tag response

A method comprising:

• transmitting a plurality of interrogation signals to activate one or more RFID tags, each of the plurality of interrogation signals being transmitted with a different polarization;
• receiving a plurality of responsive signals from the one or more RFID tags;
• analyzing received symbol quality data for each of the plurality of responsive signals using quality parameters to exclude certain polarizations to provide a selected transmit polarization subset having received symbol quality data that is above a quality threshold;
• transmitting further interrogation signals to the one or more RFID tags using the selected transmit polarization subset;
• and
• wherein transmitting the plurality of interrogation signals further comprises determining a beginning polarization, an end polarization and a polarization step size for transmitting a plurality of interrogation signals.

A system comprising:

• an antenna system having a first antenna element with a first polarization and a second antenna element having a second polarization being orthogonal to the first polarization;
• a transmitter coupled to the antenna system;
• a receiver coupled to the antenna system;
• a processor coupled to the transmitter and receiver and programmed to:
• control the transmitter to transmit a series of RFID interrogation signals to one or more RFID tags, each of the series of RFID interrogation signals having a varied transmit polarization;
• control the receiver to receive a series of responsive signals from the one or more RFID tags;
• analyze received symbol quality data for each of the series of responsive signals using quality parameters to select a transmit polarization subset having received symbol quality data that is above a quality threshold;
• and
• transmit further interrogation signals to the one or more RFID tags using the selected transmit polarization subset;
• and
• wherein the processor is further programmed to periodically re-transmit the series of RFID interrogation signals at different polarization step sizes.