Digital Signals Goodbye to Analog

As this first decade of the 21st Century draws to aprocess by which a digital signal duplicates an analog
close, so also does the age of analog. When it comesquantity is called encoding, or just simply coding.
to communications, analog has served humanity longEncoding allows the digital representation of analog
and well, but the old technology is being phased out byquantities – an area of infinite variability –
governments and manufacturers alike, and within tenby using a binary system that creates an on-off
years, the old analog systems will likely be aswitch for all those variables (theoretically). This use of
technological footnote to history. Put simply, analogdigital signals gives a major improvement in noise
equipment cannot compete with the capacity of digitalreduction.
and, as a result of simple economics, it is destined toNoise affects the inherent value of a signal, whether it
dwindle away. Of course, analog systems madeis digital or analog, but on an analog signal the noise has
sense when first created, for analog signals are ablean impact on the value of that signal, because
to duplicate virtually any natural phenomena, such asincreased voltage over an analog signal creates
sound or light, which are analog inherently becausedistortion. When an analog signal is recorded, it is
they are infinitely variable.inevitable that noise is recorded along with it. If it is then
With analog systems of communications, the biggestre-recorded, the original noise is indistinguishable from
problem has always been noise. While analog offersthe original signal, and becomes, effectively, part of the
the infinite variability that replicates the natural state ofnew signal. At each recording stage, extra noise will be
sound or light, converting those phenomena into anintroduced into the system and multiple copying of an
electrical signal and then back again into a sound or ananalog signal ultimately results in an unacceptable loss
image creates “noise.” The term is usedof quality, called generation loss.
because it can literally produce noise in an audioWhen a digital signal is recorded, it too will include noise
system – the hiss or rumble that is heard in poorpicked up within the system. However, a digital signal is
quality recordings. Noise also shows itself in the grainclearly identifiable, despite any noise the signal picks up.
or “snow” that can trouble a TV signal.At the root of the digital advantage is the fact that the
Noise affects an electronic signal at every stage ofsignals in a digital system do not have to be accurate.
the communications process, and its effects add up.A voltage only needs to be readable as a one or a
Although a digital signal cannot directly represent anzero to be processed. Thus, digital communications
analog quantity, everybody know that a digital devicesignals offer possibilities which have no equivalent in
like and Mp3 player offers excellent quality duplicationanalog systems.
of sound, which is, in fact, an analog phenomenon. The