Question
Noise will be inevitable, which causes errors to the data. What type of noise is difficult to remove from analog and digital signals? Is noise easier to remove from analog or digital signals?
Digital Signal is More Noise Tolerant
While transmitting data over a network channel, noise causes errors which may result in loss of data (Anttalainen, 2003). Digital signal is considered more noise tolerant because it uses binary signals where a bit stream is made up of a combination of ones and zeros unlike analog signals which has varying signal values that must be identified precisely. As a result of this difference, the noises that are difficult to remove are thermal noise and impulse noise for analog and digital signals respectively.
Thermal Noise
Thermal noise, also called white noise or Gaussian noise, is a continuous noise that increases as temperature rises in transmission channels and electronic gadgets (White, 2016). Removing this noise from digital signals is easily done by regenerating the signal. It is difficult to clean white noise from analog signals because several filters are required and it is uncertain whether the original signal will remain after filtering.
Impulse Noise
Impulse noise (also called noise spike), according to Forouzan and Fegan (2007), occurs when a high energy signal (spike) enters the transmission line or the electronic device suddenly. Impulse noise can sometimes completely destroy digital signals by misplacing multiple bits making it difficult to determine 1s and 0s in the affected bit stream. Digital signals can be recovered from impulse noise provided that the signal has not been completely destroyed. Although signal spike affects analog signals, installing special filters can prevent impulse noise error.
Digital Signal: The Easiest to Clean
It is easier to remove noise from digital signal than from analog signals. Digital signals are made up of binary numbers which means a digital signal’s bit stream has ones and zeros. Booth and McDuell, (2002) argues that the strength of signals reduce as they travel because random noise signals are picked. Cleaning digital signal becomes easier since it involves filtering out the random noise particles and amplifying the binaries back to their initial state. Cleaning analog signal is difficult because they are made up of random values which can resemble the values picked inform of noise.
Reference
Anttalainen, T. (2003). Introduction to telecommunications network engineering. 2nd ed. Norwood, MA: Artech House, p.79.
Booth, G. and McDuell, G. (2002). Modular science for Edexcel. Oxford: Heinemann, p.127.
Forouzan, B. A. & Fegan, S. C. (2007). Data communications and networking. 4th ed. New York: McGraw-Hill Higher Education, pp.84.
White, C. M. (2016). Data communications & computer networks: a business users approach. 8th ed. Boston, MA: Cengage Learning., p. 151.
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