Recent developments in the field of very high power S-band duplexers

A screen duplexer is mainly composed of a total coupler and a series of cylindrical gas tubes in the coupling window plane, in parallel to the shorter side of the waveguide. When transmitting, the microwave energy ionizes the gas tubes and partly reconstitutes the waveguide wall. The energy is directed to the antenna. When receiving, the electrical field is too weak to ionize the tubes. Microwave energy is transmitted to the secondary section of the coupler where the receiver is located. Those tubes have to withstand high temperatures, they must absorb an as small as possible energy, and have a low recovery time.