There are three orbital patterns used in satellite communication:

• Circular polar orbit
• Inclined elliptical orbit
• Circular equatorial orbit
• Geo synchronous orbit
• Geo stationary orbit
• Clarkes orbit

• The polar orbiting satellite follows an orbit that is close to earth and passes over the poles i.e. Inclined in nearly 900.
• The average height of this orbit is typically 800 to 1000Km above earth.
• Satellite in this orbit are mainly for earth observation and surveillance and for resarchwork.
• When satellite is inclined in highly elliptical orbit, centre of the earth is one of the focal point of ellipse .
• In this case the distance of the satellite from earth varies depending upto its position.
• Satellites in this orbit are used when communication is required in high altitude region.
• The geo-synchronous orbit is located at a height of 22282 miles above the earth in earth equatorial plane.
• A satellite moving in geo synchronous orbit in same direction as the earth’s surface with forward velocity of 6874mph will complete the orbit in 24 hrs. The satellite will therefore appear stationary with respect to earth and hence it is called geo stationary satellite and orbit is called geo stationary unit.