Describe the antenna subsystem of satellite.

Describe the antenna subsystem of satellite. 
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Answer :

Antennas on the satellite serve as an interface between the earth stations on the ground and various satellite subsystems during operations Antennas receive the uplink signals and transmit the downlink signals. In addition they provide single link for the satellite telemetry, command and ranging systems which in conjunction with attitude control subsystem provides beacon tracking signals for precise pointing of the antenna towards the Earth coverage areas. Most of the antennas are highly directional gain antennas that must be accurately pointed. The design of a satellite antenna is conditioned by the required coverage area. The antennas in antenna subsystem can be linear,dipole,helix,horn,antenna array and the parabolic reflector. The parabolic reflector is the most commonly used one as it gives a highly directional symmetrical pattern. In the satellite antenna it is essential that the antenna main lobe should be such that the energy is concentrated towards the earth station and hence maximizing the EIRP It should be remembered that antennas are the one of the key elements in a satellite communication system since their gain values directly determine the amount of received power.


Types of antenna system use in satellite communication: 

Parabolic antenna 

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