This is similar to transmitting a bit stream over the necessary channel. The answer to this question lies in the technology known as Digital Video Compression. Of all the technological advancements, perhaps only a few can be categorized as major breakthroughs- transistorized equipment, the advent of satellites being developed and the deployment of fiber optics. This is due to spectrum availability. Spectrum is the frequency range in which over the air or microwave signals travel.
Different frequencies occupy different areas of the spectrum.
Believe it or not the usable spectrum for microwave signals is a limited resource. Most of the spectrum has been allocated, and we need to better utilize this resource. The technology of Digital Video Compression will allow us to have ten or more times the number of channels in the same spectrum occupied by analog channels. Compression also has proven itself when it comes to satellite transponder availability. It is extremely expensive to rent or own space on a satellite channel, and compression allows satellites to transmit and receive information using much less bandwidth with no apparent loss of quality.