What is Satellite Internet and How Does it Work?

VSAT is an acronym for Very Small Aperture Terminal, and generally refers to a satellite dish of 3.8m or less located at the remote location. Satellite communication is used for internet connection in remote areas of the world where a connection to the traditional copper or fibre network is not possible. It is also used as a backup communication link for mission critical systems such as remote autonomous mine sites and offshore Oil and Gas rigs.

VSAT links are used for both internet data and voice (VoIP – Voice over IP) traffic.

There are many different types and sizes of satellite dish and equipment to choice depending on the frequency band, satellite orbit, bandwidth, network topology, etc.

Internet speed can vary between 128kbps or up to 72Mbps and above for luxury cruise liners! How fast the link depends on your budget!

VSAT Satellite Orbits

Positioned one-tenth of the way to the moon (about 36,000 km) are Geostationary  (GEO) communication satellites. Many satellite service providers use Geo stationary satellites as they appear to be stationary viewed from Earth and therefore can use a fixed dish. However, tracking antennas can also be used in VSAT for MEO satellite like the O3B network or for satellites in inclined orbit.

Satellite Teleport Hubs

At the other end of the link will be larger satellite dishes located at a Teleport. This is where the satellite service provider will have all the RF and network equipment that breaks out to the internet. The service providers usually have two separate internet connections on fibre to provide redundancy.

Satellite Coverage Maps

It is impossible for one single satellite to cover the entire globe so hundreds of satellites have been launched and cover the major areas of population and trade routes.

Basic VSAT Equipment

Finally, the basic equipment at a remote site consists of the following:

• Satellite Dish – The reflector used to receive and transmit the radio signal
• BUC – Block UpConverter – Transmitter
• LNB – Low Noise Block – Receiver
• Coax Cables – Used to connect the outdoor equipment to the indoor equipment
• Modem – Used to modulate and demodulate the signal (SCPC or TDMA)

Also you will need the IT equipment you want to connect to the internet with and VoIP (Voice over IP) Phones.