A phase shifting diode detector system for an RFID reader. Quarter-wave delay circuitry is coupled between a forward transmitted signal of the RFID reader applied at a first end of the delay circuitry, and a reflected signal returning from an RFID tag applied at a second end of the delay circuitry. The...http://www.google.fr/patents/US7456746?utm_source=gb-gplus-shareBrevet US7456746 - Quarter wave phase shifted diode detector circuit
