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Enlighten Me!

How Does Satellite TV Work?

Nine ‘o’ clock. It’s time for your favourite serial on television. Have
you ever wondered how the same serial can be viewed by millions
of people across the world?

This is possible because of satellite television technology. It uses
man-made or artificial satellites to send your favourite serial to
your television set. But why do we need satellites for this purpose?

The earth is round
To understand this, we have to first take a look at the shape of our
earth. Indeed, the earth is a sphere. This means if I were to send signals from one place to another on
the earth’s surface, the signals would sooner or later get lost on the curved surface.

This is the reason why radio and television towers are very tall. The taller the tower, the farther the
signals go. Each tower gathers signals and beams them to the television sets which capture them using
their antennas.

However, making and maintaining these towers can be very expensive. Also, the area to which a
television tower can send signals is small. This is why we need a satellite. It is used to send signals to
television sets all over the world.

A geo-stationary satellite

A geo-stationary satellite is a satellite which remains fixed over a particular area on the earth’s surface.
Actually, it rotates at the same speed as the earth. Hence, it appears to be fixed.
These satellites are quite useful things. They can be used to beam a signal to any part of the earth’s
surface. When you send a signal to this satellite, it can reflect the signal back to the earth or transmit it
to another satellite. This way, your signal can reach anywhere on earth.

Television broadcasting companies convert
television programmes into signals. These
signals are then beamed to satellites, which,
in turn, reflect them back to the earth, where
they are gathered by dish antennas, installed
by the cable operators. The cable operator
then transmits these signals through the local
cable network to your television.

In this entire broadcasting process, satellites
behave only as reflectors in the sky which
gather and re-transmit the television signals.

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