Introduction to SNG and ENG Microwave

Satellites and orbits

In October 1945, the famous science fiction author Arthur C. Clarke wrote an article which was published in a British radio hobbyist magazine. In that article, he put forward an idea about how the coverage of TV transmissions could be improved by using radio ‘relays’ situated above the Earth’s atmosphere. These relays are what we now call communications satellites.

The principle of the satellite is that it can be put into an orbit at a distance of about 35 000 km from the Earth’s surface so that as it orbits the Earth its speed of rotation exactly matches the speed of the Earth’s rotation. The effect of this is that the satellite appears stationary from any point on the Earth’s surface (geostationary) that can ‘see’ the ...