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Methods Of Error Detecting Code

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Introduction The most common method of transmitting information include use of bit strings. It's beyond bounds of possibility to evade errors when data is stored, recovered, operated on or transmitted. The likely source for this errors include electrical interference, noisy communication channels, human error or even equipment error and storing data for a very long time on magnetic tapes.. Important to consider therefore is ensuring liable transmission when large computer files are transmitted very fast or say when data is sent over a very long distance and to recover data that have degraded due to long storage on tapes. For a reliable transmission of data, techniques from coding theory are used. It is done in a such a way …show more content…

in case this is done, errors will not only be able to detected but also corrected . In short , in case sufficiently few errors are made in the transmission of a codeword, it becomes very easier to determine which codeword was sent. the following examples illustrate the idea. Application include television cameras. Hamming Distance when it comes to information theory, Hamming distance refers to the number of bits which are the difference between two binary strings. expressed alternatively,, the distance between two strings A and B is ∑ | Ai - Bi |. simply put in a similar way is that it determines the minimum number of substitutions required to alter one string into the other, or the lowest number of errors that could have changed one string into the other. large application is in coding theory, more specifically to block codes, in which the equal-length strings are vectors over a finite field. Perfect Codes Perfect Codes refers to those codes that achieve the Hamming bound .A good example include those codes that have just a single codeword, and also those codes that are the whole of . Another perfect example can be illustrated by the repeat codes, where each symbol of the message is duplicated an odd fixed number of times so as to obtain a codeword whereby q = 2. Both of these examples are often referred to as the trivial perfect codes. In the year 1973, it was confirmed that any non-trivial perfect code over a prime-power

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