Full-wave rectifier and method of operation for a recognition system

An improved full-wave rectifier for a transponder, said transponder being formed on a one substrate and associated with a matching member which operates to control a control mechanism of a device;

• the matching member and other non-matching members containing facilities each of which, when receiving energy transmitted from a transmitter/receiver an antenna produce a respective unique recognition signal in the transponder;
• control of the device being possible only upon simultaneous occurrence of both operation of the control mechanism and production of a recognition signal by the matching member;
• wherein the improved full-wave rectifier comprises:
• a first transistor and a second transistor in combination forming a first transistor pair for minimizing voltage drop between ground and the transponder substrate;
• a third transistor and a fourth transistor in combination forming a second transistor pair for minimizing the voltage drop between the alternating current peak voltage and the output voltage of said full-wave rectifier;
• said first transistor pair and said second transistor pair being controlled by alternating current voltage input signals to produce a full-wave rectified alternating current voltage output;
• and
• a regulator circuit for decoupling said first transistor pair and said second transistor pair from capacitive loads of said full-duplex transponder.