Editing Satellite Internet access (section)

====Outdoor unit (ODU)====
At the far end of the outdoor unit is typically a small (2–3-foot, 60 to 90&nbsp;cm diameter), reflective dish-type radio antenna. The VSAT antenna must also have an unobstructed view of the sky to allow for proper [[Sightline|line-of-sight]] (L-O-S) to the satellite. 
There are four physical characteristic settings used to ensure that the antenna is configured correctly at the satellite, which are: [[azimuth]], elevation, [[Antenna (radio)|polarization]], and [[Skew (antenna)|skew]]. The combination of these settings gives the outdoor unit a L-O-S to the chosen satellite and makes data transmission possible. These parameters are generally set at the time the equipment is installed, along with a beam assignment (K<sub>a</sub>-band only); these steps must all be taken prior to the actual activation of service.
Transmit and receive components are typically mounted at the focal point of the antenna which receives/sends data from/to the satellite. The main parts are:
* Feed – This assembly is part of the VSAT receive and transmit chain, which consists of several components with different functions, including the feed horn at the front of the unit, which resembles a funnel and has the task of focusing the satellite microwave signals across the surface of the dish reflector. 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.
* [[Low-noise block downconverter]] (LNB) – This is the receiving element of the terminal. The LNB's job is to amplify the received satellite radio signal bouncing off the dish and filter out the noise, which is any signal not carrying valid information. The LNB passes the amplified, filtered signal to the satellite modem at the user's location.