The antenna subsystem are complicated mechanical assemblies that are folded into dense
packet for launch and must be deployed in large accurately alight assembly during orbit.
Antenna receive the uplink signal and transmit the downlink signal .In addition they provide
a signal link for satellite telemetry command and ranging system which alone with the
attitude control sub system provide tracking signal for precise pointing of antenna towards
the earth coverage area.
Satellite communication system uses a variety of antenna system. This maybe linear dipole,
helix, horn antenna array and parabolic reflector. However, the parabolic reflector is most
commonly used antenna as it gives a highly directional symmetric radiation pattern.