Uplink Antenna for Transmitting

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The antenna system used by most of the TV stations is double reflected parabolic antenna. It has 3 major parts.
-    Horn antenna
-    Parabolic Sub reflector
-    Parabolic Main reflector
Horn Antenna: The waveguide has come to this portion. The certain volume of electromagnetic wave comes here with high energy. For radiation, the horn antenna acts like a radial source (theoretically unidirectional ).
Figure: Radiation sequence from the antenna system
Parabolic Sub-reflector: The high energetic volume of electromagnetic wave radiated from the horn antenna comes to the sub-reflector and reflected back to the main reflector.
Parabolic Main Reflector: The reflected electromagnetic wave from sub reflector comes to the main reflector and according to the law of reflection of the reflected parallel waves, it radiates finally for the travel to satellite.  

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