Feed horn

The feed horn minimizes the mismatch loss between the antenna and the waveguide.

When used with a offset, parabolic or lens antenna, the phase center of the horn is placed at the focal point of the reflector.

The feedhorn then connects via a short waveguide to the "low-noise block downconverter" (LNB), a small housing containing a part of the reception electronics (also called the "RF front end").

This LNB converts the high satellite microwave downlink frequencies to lower frequencies, so the TV signals can be more easily transmitted through coaxial cables to receivers located anywhere inside a building.

Feedhorns are also used in applications like radar, line-of-sight microwave transmission or radio astronomy.