Actually microwaves are the principal part of the electromagnetic spectrum used for satellite communications. Radio waves principal benefit is that they pass through most solid objects like brick etc making them convenient for radio - where the receiver is usually placed inside a dwelling.
par
Pat Hawkins , Procurement Specialist , Valiant Integrated Services
Gooday
For Satellite Comms I would think that just about any form of frequency of light will work, but to communicate with a satellite from earth, radio waves have several advantages. The most key of which is absorption.
The majority though of Sat Comms is done via microwave rather than radio due to the fact that microwaves can carry more data than radio waves, as they have a much higher frequency, so there is more bandwidth in the microwave wave for modulation techniques (these are the ways the signals are manipulated to add information to them).
Current bands for Sat Comms are C, Ka, Ku and X Bands.
Pat
