How are geostationary satellites used for communication?

2 Answers

They are placed so that the orbitals speed will be same with Earth.


So they remain above same place on earth 3 Such satellites can cover the whole earth for communication..THey canenter image source here be used as relay station for TV, and other communications covering whole world..
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Aug 15, 2016

Relative to the Earth, geostationary satellites remain stationary ( at rest ), vertically above a point on the Earth's surface.


Geostationary satellites have period of rotation about Earth's center

as 1 day. They are placed at an altitude of about 35800 km, The

orbit direction relative to the Earth synchronizes with that of the

Earth's day/night spin. They remain stationary ( at rest, relative to

the Earth, ) vertically above a point on the Earth's surface.

They can receive and transmit signals from a part of the the Earth's

surface in the form of a spherical cap that is symmetrical about their


For the altitude 35800 km, the spherical cap subtends a conical


#cos^(-1)(6378/(6378+35800))=81.30^o# at the center of the


Conical angle #2pi=720^o# covers the entire spherical surface.

So, the proportion of the Earth's surface covered by one such


#=81.30/720 X 100%=11.29%#.

Tesselation (dividing the surface into caps without gaps) is not


To cover the entire globe, overlapping cannot be avoided. .