Two way communication-Internet via DTH-Satellite internet:
The feed horn :Both receives signals reflected off the dish’s surface and transmits outbound signals back to the satellite.
Block upconverter (BUC) – This unit sits behind the feed horn and may be part of the same unit, but a larger (higher wattage) BUC could be a separate piece attached to the base of the antenna. Its job is to convert the signal from the modem to a higher frequency and amplify it before it is reflected off the dish and towards
the satellite.
Credit:Wikipedia