But then the disadvantages that, since the distance, the covered distance
is about 36.000 kilometres up above the surface of the earth, you require
high transmitter power, and large receiving antenna gains, because the
free path lost is of the order of 200 dB.
The service to high altitudes are not possible, because the geostationary
orbit satellites, which are in the equatorial plane, their signals do
not appreciably reach the higher latitude places. And, I have already
mentioned, that each of these will have large signal propagation time,
two-way propagation delay for geosynchronous earth orbit satellite, depending
on where you are, is of the order of 270 milliseconds. And coverage to
urban area is a problem at these higher altitudes, and it also has the
effects due to shadowing.
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