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`Error floor - Wikipedia
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`Error floor
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`The error floor is a phenomenon encountered in modern iterated sparse graph-based error correcting codes like LDPC
`codes and turbo codes. When the bit error ratio (BER) is plotted for conventional codes like Reed–Solomon codes under
`algebraic decoding or for convolutional codes under Viterbi decoding, the BER steadily decreases in the form of a curve as
`the SNR condition becomes better. For LDPC codes and turbo codes there is a point after which the curve does not fall as
`quickly as before, in other words, there is a region in which performance flattens. This region is called the error floor
`region. The region just before the sudden drop in performance is called the waterfall region.[1]
`
`Error floors are usually attributed to low-weight codewords (in the case of Turbo codes) and trapping sets or near-
`codewords (in the case of LDPC codes).[2]
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`References
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`1. Ryan, W. E. and Lin, S.: Channel Codes: Classical and Modern, Cambridge University Press
`2. Thomas Richardson: Error floors of LDPC codes. http://ldpccodes.com/papers/ErrorFloors.pdf
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`Retrieved from "https://en.wikipedia.org/w/index.php?title=Error_floor&oldid=537526929"
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`This page was last edited on 10 February 2013, at 11:35.
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`https://en.wikipedia.org/wiki/Error_floor
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