A satellite dish is a vital device designed with the specific purpose of transmitting and receiving signals from satellites. They come in varying sizes and are used to send and receive signals for satellite television. The transmitting dish consists of a bowl shaped antenna and a central feed horn. A controller sends a signal through the horn and the dish focuses the signal into a narrow beam. Want to learn more? visit us.
The dish at the receiving end works in the exact opposite way of the transmitting dish. When it receives a signal, the bowl-shaped disc reflects the signal inward onto the feed horn, which then passes the signal onto the receiving equipment.
The size of modern satellite dishes vary from 18 inches to 31 inches in diameter. They are fixed in one position and receive signals from one orbital position.
In some systems, the dish needs to pick up signals from two or more satellites at the same time. These dishes are equipped with two or more horns to pick up different satellite signals. As the beams from different satellites hit the curved dish, they reflect at different angles so that one-beam hits one of the horns and another beam hits a different horn.
A key element in the feed horn is a low noise blockdown converter or LNB. The LNB amplifies the radio signal and filters out the noise. It transmits an amplified, filtered signal to a satellite receiver inside a viewer’s house. The quality of a satellite dish is usually expressed as a G/T ratio. This is the ‘gain’ or signal amplification of the dish divided by the amount of noise the LNB produces. The gain depends on many factors including surface finish , uniform shape and the quality of the feedhorn. The amount of noise a LNB produces depends on design, temperature and losses in the cables.