Satellite TV is a buzzword among the techno-buff community as well as the television viewers. How does satellite television work? How do satellites facilitate television-viewing? An understanding of the technology behind the working of a satellite TV can provide us with the answers. Let's find them.
What is Satellite TV?
Satellite TV is the television system wherein communication satellites orbiting the Earth bring about the transmission of television signals. It is a wireless system that facilitates the relay of TV programs by means of satellite communication.
In many countries around the world, satellite television services are used for providing the consumers with more number of TV channels and a wider range of services. Do you know when the first satellite TV signal was relayed?
It was way back in 1962 that the first satellite television signal went from Europe to the Telstar satellite over North America. Anik 1, a domestic geostationary satellite of Canada was the first of its kind to carry television signals. From then, there was no looking back and the popularity of satellite television continues to rise.
How does It work?
The satellites that aid the transmission of television signals have elliptical or geostationary orbits. The satellite television setup consists of a transmitting antenna or uplink satellite dishes pointed towards specific satellites. The dishes have large diameters, which help in increasing the signal strength and enable accurate aiming at the satellite.
The satellite houses transponders, which receive signals from the antenna. The uplinked signals are tuned to a frequency range that corresponds to that of the transponders. The transponders retransmit the signals back to Earth.
Before they are retransmitted, the signals undergo a process of translation wherein they are transmitted at a different frequency band in order to avoid interference with the uplink signal.
The signals that are transmitted by the transponders on a satellite are received by the parabolic dish. On account of traveling a substantially large distance, the signal received by the dish is weak.
The signal is reflected towards the feedhorn, a device mounted at the focal point of the dish. The function of a feedhorn is to collect the received signal and conduct it towards the low-noise block downconverter (LNB).
The LNB amplifies the signal and converts it to a frequency that is suitable for transmission over a cable, precisely to the L-band range. The LNB transmits the signal over the intra-facility link (IFL) to the satellite receiver. IFL refers to the coaxial cable that connects the indoor and outdoor satellite equipment.
Owing to the LNB, the handling of L-band signals becomes easy. Also, low-cost cables can be used to connect the television receiver with the TV dish and the LNB. The satellite receiver sends the signals to the television set and it is ready to come alive!
While you are lazily flicking through television channels, the satellite communication system is busy delivering content. So the next time you switch on your TV, surely you will take a moment to think of all that goes behind the relay of radio signals to your television set.