Field and Wave Electromagnetics 2nd Edition by David Cheng

Exercise 16

Show that three satellites equally spaced around the geosynchronous orbit in the equatorial plane would cover almost the entire earth's surface. Explain why the polar regions are not covered. (b) Assuming the main beam of the radiation pattern of the satellite antenna to have the shape of a circular cone that just covers the earth with no spillover, find a relation between the main-lobe beamwidth and the directive gain of the antenna.