What is digital communication ?
Digital communication systems, by definition, are communication systems that use such a digital
sequence as an interface between the source and the channel input (and similarly between the
channel output and final destination).
The idea of converting an analog source output to a binary sequence was quite revolutionary
in 1948, and the notion that this should be done before channel processing was even more
By today, with digital cameras, digital video, digital voice, etc., the idea of
digitizing any kind of source is commonplace even among the most techno-phobic. The notion
of a binary interface before channel transmission is almost as commonplace. For example, we
all refer to the speed of our internet connection in bits per second.
There are a number of reasons why communication systems now usually contain a binary inter
face between source and channel (i.e., why digital communication systems are now standard).
These will be explained briefly they are as follows:
• Digital hardware has become so cheap, reliable, and miniaturized, that digital interfaces are
• A standardized binary interface between source and channel simplifies implementation and
understanding, since source coding/decoding can be done independently of the channel,
and, similarly, channel coding/decoding can be done independently of the source. For more information download notes here. .