Microwave transponder for transceiver interrogation - includes microwave circuits built on dielectric surfaces to provide unique response coded signal

摘要

The transponder which is intended to receive an interrogation signal transmitted by a transmitter-receiver, returns to the transmitter-receiver an echo signal which gives a code characteristic of the transponder. The latter includes a card consisting of a plate of dielectric on the surface of which is a single radiating surface formed using microband techniques. The plate serves as a receiving aerial for interrogation signals, and a transmitting aerial for the double frequency response signal. Another plate is covered with conducting material and resides immediately behind the first to serve as an earth plate. A third plate (behind again) carries microwage circuits for rectification, filtering, frequency conversion, modulation and coding.