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Satellite Frequencies - Consideration of Rain Fade and Antenna Size

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As on above picture, on VSAT system, the higher the frequency, the smaller will be the antenna size. Against on it, more impact of rain attenuation suffered by the higher frequency (e.g Ka and Ku band)



To mitigate of rain fade attenuation, there are some techniques ;

- On Forward Link :
     Use of DVB S-2 with Adaptive Coding and Modulation
     Automatic Uplink Power Control (AUPC)

- On Return Link :
     Adaptive Coding
     Symbol Rate Change
     Automatic Uplink Power Control (AUPC)



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