Why satellite?
Even with the proposed rollout of Broadband in the Argyll and the Islands area there will still be locations that will not be covered under the new system. Satellite systems are the only technology that offers 99% coverage in our area.
So no matter how remote your business or house you can get Internet access with download speeds of up to 512 kilobits per second (kbps). This is in comparison to speeds attainable over your telephone line of 40-50 kbps with normal dial up access. The satellite system therefore offers almost ten times faster download speeds.
The upload speed varies with supplier, some, such as the one way satellite systems, because they utilise your existing telephone line, only offer speeds up to 33kbps. (One-way systems also tend to offer lower download speeds as well, usually in the 400kbps region). The average upload speed tends to be about 128kbps about 4 times faster than an average telephone line.
When considering a satellite system you will need to take into account the possible siting of the dish to provide a good view of the southern sky (your provider will arrange for a site survey in advance of any installation). You may also need to apply for planning permission if you are located in a listed building.
How do they work?
A signal is sent from a dish mounted at your site to a satellite in orbit around the Earth this is then bounced down to a ground station connected to the Internet. The return signal comes from the ground station back to the satellite and then down to your remote satellite dish. A special modem connects the dish to your PC or Network. This is how two-way satellite communications operate.
Your dish, from 68cm to 1 metre in diameter depending on location, is pointed at a satellite in geostationary orbit around the Earth. This means that it is moving at the same speed as the Earth’s rotation hence they appear to be stationary from the surface of the Earth. Most of the commercially available satellites in the Intelsat system are orbiting over the equator, about 22,250 miles up, therefore there is a time lag as the signal travels from your dish to the satellite and then back down to the ground station. This ground station has a direct link into the Internet. The information that you have requested, a web page or a file, has to make the same journey in reverse. This delay between you making a request and the information actually arriving is called the latency of the system.
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