Beam waveguide antenna

Diagram of a beam waveguide antenna from NASA, showing the signal path (red)

A beam waveguide antenna is a particular type of antenna dish, at which waveguides are used to transmit the radio beam between the large steerable dish and the equipment for reception or transmission, like e.g. RF power amplifiers.

34-meter beam waveguide antenna at NASA's Deep Space Communications Complex site outside Madrid, Spain, part of the NASA Deep Space Network.