Downlink is a communication link between a satellite and a ground station. In general, downlink contains HM data and payload related data primarily.

==Flow of Data for Downlink ==

# '''Acquisition and Encoding of data:''' Different types of data gathered by the OBC which need to be transmitted to the ground-station. Further, this data needs to be encoded/packeted.

# '''Modulation of data:''' Now this data needs to be modulated on the desired carrier frequency.