ABSTRACT

Baseband signals such as speech, music and video are naturally occurring analog signals. Digital signals, on the other hand, are obtained by coding analog signals, and making it simpler to transmit the information. The Morse code is probably one of the oldest, and a classic example of digital coding; the entire English alphabet is represented by a combination of dashes and dots. For example, the emergency message SOS (Save Our Souls) is represented by the following code:

SO S … - - - …

The main advantage is that even though the English language has 26 different looking and different sounding alphabets, all of them can be reduced to a combination of the same two characters, the dot and the dash. At the receiver, only these two characters need to be recognized correctly for reconstructing any message accurately. Of course, the receiver has the additional task of decoding the actual message from the combination of dots and dashes.