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1. An advantage of a digital signal is that it is not amplified. What does this mean?
Thanks!
2. Bump.
3. (Original post by Wolfram Alpha)
An advantage of a digital signal is that it is not amplified. What does this mean?
Thanks!
Analogue signals are continuous functions. The signal has both amplitude and frequency components. Attenuation of the signal occurs as transmission propagates along conductors or a vacuum or through any gaseous or solid material. In order to recover the signal both in amplitude and frequency, the receiver must first amplify it to a useful level. This has the disadvantage that unwanted noise and interference will also be amplified unless some form of discrimination is used with varying degrees of success.

Digital signals are a numerical (encoded mathematical) representation of an analogue signal comprising the original signal's amplitude and frequency information in binary form. The encoded information within a digital signal does not rely on the amplitude of the digital signal for information. To recover the original analogue information, the digital representation of the analogue signal merely needs to cross an arbitrary threshold level from which the original intended signal can be extracted.

i.e. The digital signal conveys a mathematical description of the original analogue signal in both amplitude and frequency. It's that mathematical description which gets transmitted and nothing else. Recovery of the information does not require linear amplification as needed with an analogue signal.
4. (Original post by uberteknik)
Analogue signals are continuous functions. The signal has both amplitude and frequency components. Attenuation of the signal occurs as transmission propagates along conductors or a vacuum or through any gaseous or solid material. In order to recover the signal both in amplitude and frequency, the receiver must first amplify it to a useful level.
I am still confused about the meaning of amplify...

(Original post by uberteknik)
The encoded information within a digital signal does not rely on the amplitude of the digital signal for information. To recover the original analogue information, the digital representation of the analogue signal merely needs to cross an arbitrary threshold level from which the original intended signal can be extracted.
Does that simply mean that for analogue signals the information is obtained from the height (amplitude) of the signal?

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