As the signal generated on satellite passes through long distances, it picks up some disturbance and is attenuated. After reception on antenna, it is decoded, post which, it is processed to check whether the received data is accurate. Take for example, GPS. The location on your electronic device does not show the moment you start the app. Its because the GPS processor for about a minute checks the consistency i.e. let’s say it gathers location data twenty times in a minute, it checks the accuracy of signal received by the repetition in data and gps mechanism's inbuilt quality checks. The mechanism is complex but the underlying fact is that every data received from a satellite must be double-checked before claiming it to be accurate and usable.

The above image shows a typical internet link, between ground and satellite. This can however be generalised to any satellite. The various analogies:

# Pre-router: Stored data to be sent