Editing Satellite Internet access (section)

===Antenna dish and modem===
For the customer-provided equipment (i.e. PC and router) to access the broadband satellite network, the customer must have additional physical components installed:

====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.

====Indoor unit (IDU)====
The satellite [[modem]] serves as an interface between the outdoor unit and customer-provided equipment (i.e. PC, router) and controls satellite transmission and reception. From the sending device (computer, router, etc.) it receives an input [[bitstream]] and converts or modulates it into radio waves, reversing that order for incoming transmissions, which is called [[demodulation]]. It provides two types of connectivity:
* Coaxial cable (COAX) connectivity to the satellite antenna. The cable carrying electromagnetic satellite signals between the modem and the antenna generally is limited to be no more than 150 feet in length.
* [[Ethernet]] connectivity to the computer, carrying the customer's data packets to and from the Internet content servers.
Consumer grade satellite modems typically employ either the [[DOCSIS]] or [[WiMAX]] telecommunication standard to communicate with the assigned gateway.