Subject: Advance Communication System

Difficulty: Medium

Marks: 4 marks

• 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.