What is satellite?

In essence, a satellite is a form of amplifier made up of a series of transponders. It receives signals from the Earth, amplifies them, and then transmits them back to earth at different frequencies. Each transponder can handle around 2400 compressed telephone calls or a standard TV channel. Each satellite carries somewhere between 16 and 40 transponders.

Satellite communications were once the exclusive domain of space agencies, governments and the military. However, relaxation of regulations, advancing technology and lower prices have meant that even relatively small businesses can now have access to, and enjoy the benefits of, the latest satellite technology. There are estimated to be well over 300,000 small satellite terminals dotted around the world.

It’s something of a myth that all satellite ventures are prohibitively expensive. On either end of the scale, it costs just a few thousand pounds for an amateur satellite to hitch a ride on a commercial launch, to literally thousands of millions of pounds for a state-of-the-art spy satellite. Commercial and private satellites fall somewhere in between these extremes. There are two major types of satellite: the low earth orbit satellite and the geostationary orbit satellite.

Low orbit earth satellites
Many of the latest generation of small communications satellites are "low earth orbit" (LEO) satellites, which cost from a few million pounds upwards, and are launched to orbit the Earth at a distance of a few hundred miles. At this altitude, it takes them only a matter of hours to complete a full rotation around the globe. The higher the satellite is launched, the longer it will take to complete the circle.

Geostationary satellites
Geostationary satellites are generally large commercial ventures financed by international consortia. These are placed over the Equator and put into an orbit about 36,000km away from the earth which follows the same direction as the rotation of the Earth. From the Earth, therefore, these satellites appear as a fixed point in the sky. Geostationary satellites are capable of viewing 42% of the Earth’s surface and can provide coverage of large defined areas. Antennas on the ground can be permanently trained on the satellites to send or receive data.

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SatLink is rather like an international private circuit in the sky. It's designed for your exclusive use and is delivered directly to the location or multiple locations of your choice through roof-top dishes.

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SatStar enables multiple locations to exchange information with a central site via a BT hub and small satellite dishes at each site.

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Broadcast Data Service is a full-time private network offering one-way data communications from a central location to as many locations as required.

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