Convolutional code
In telecommunication, a convolutional code is a type of error-correcting code that generates parity symbols via the sliding application of a boolean polynomial function to a data stream. The sliding application represents the 'convolution' of the encoder over the data, which gives rise to the term 'convolutional coding'. The sliding nature of the convolutional codes facilitates trellis decoding using a time-invariant trellis. Time invariant trellis decoding allows convolutional codes to be maximum-likelihood soft-decision decoded with reasonable complexity.
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- enIn telecommunication, a convolutional code is a type of error-correcting code that generates parity symbols via the sliding application of a boolean polynomial function to a data stream. The sliding application represents the 'convolution' of the encoder over the data, which gives rise to the term 'convolutional coding'. The sliding nature of the convolutional codes facilitates trellis decoding using a time-invariant trellis. Time invariant trellis decoding allows convolutional codes to be maximum-likelihood soft-decision decoded with reasonable complexity.
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- enIn telecommunication, a convolutional code is a type of error-correcting code that generates parity symbols via the sliding application of a boolean polynomial function to a data stream. The sliding application represents the 'convolution' of the encoder over the data, which gives rise to the term 'convolutional coding'. The sliding nature of the convolutional codes facilitates trellis decoding using a time-invariant trellis. Time invariant trellis decoding allows convolutional codes to be maximum-likelihood soft-decision decoded with reasonable complexity. The ability to perform economical maximum likelihood soft decision decoding is one of the major benefits of convolutional codes. This is in contrast to classic block codes, which are generally represented by a time-variant trellis and therefore are typically hard-decision decoded. Convolutional codes are often characterized by the base code rate and the depth (or memory) of the encoder . The base code rate is typically given as , where n is the raw input data rate and k is the data rate of output channel encoded stream. n is less than k because channel coding inserts redundancy in the input bits. The memory is often called the "constraint length" K, where the output is a function of the current input as well as the previous inputs. The depth may also be given as the number of memory elements v in the polynomial or the maximum possible number of states of the encoder (typically : ). Convolutional codes are often described as continuous. However, it may also be said that convolutional codes have arbitrary block length, rather than being continuous, since most real-world convolutional encoding is performed on blocks of data. Convolutionally encoded block codes typically employ termination. The arbitrary block length of convolutional codes can also be contrasted to classic block codes, which generally have fixed block lengths that are determined by algebraic properties. The code rate of a convolutional code is commonly modified via symbol puncturing. For example, a convolutional code with a 'mother' code rate may be punctured to a higher rate of, for example, simply by not transmitting a portion of code symbols. The performance of a punctured convolutional code generally scales well with the amount of parity transmitted. The ability to perform economical soft decision decoding on convolutional codes, as well as the block length and code rate flexibility of convolutional codes, makes them very popular for digital communications.
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- Code
- Is primary topic of
- Convolutional code
- Label
- enConvolutional code
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- web.archive.org/web/20140522015414/http:/www.mathworks.fr/fr/help/comm/convolutional-coding.html
- www.eccpage.com/
- www.inference.phy.cam.ac.uk/mackay/itila/
- www.ni.com/white-paper/14917/en/
- web.mit.edu/6.02/www/s2009/handouts/labs/lab5.shtml
- www5.tu-ilmenau.de/nt/de/teachings/vorlesungen/itsc_master/folien/script.pdf
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- Adder (electronics)
- Algebraic normal form
- Algorithm
- Andrew Viterbi
- BCJR
- BCJR algorithm
- Bit shift
- Block code
- Boolean logic
- Cassini probe
- Category:Error detection and correction
- Claude Berrou
- Concatenated code
- Concatenated error correction code
- Convolution
- David J.C. MacKay
- Degree of a polynomial
- Digital video
- Digital Video Broadcasting
- Error floor
- File:Conv code 177 133.png
- File:Convolutional codes PSK QAM LLR.svg
- File:Convolutional code trellis diagram.svg
- File:Convolutional encoder non-recursive.png
- File:Convolutional encoder recursive.svg
- File:Four-state RSC code.png
- File:GSM convol code.png
- File:Lenss.png
- File:Recnonrecber.png
- File:Sixteen-state RSC code.png
- File:Soft34.png
- File:Turbo codes scheme.png
- File:Two-state RSC code.png
- Finite impulse response
- Finite-state machine
- Forward error correction
- Generator polynomial
- GSM
- Hamming distance
- Infinite impulse response
- INTELSAT
- Low-density parity-check code
- LTI system
- Mars Exploration Rover
- Mars Pathfinder
- Maximum a posteriori
- Maximum likelihood
- Memory register
- Mobile communications
- Peter Elias
- Pioneer program
- Punctured code
- Quantum convolutional code
- Rational function
- Reed–Solomon error correction
- Robert Fano
- Satellite communications
- Sequential decoding
- Serial concatenated convolutional codes
- Shannon's theorem
- Shannon-Hartley theorem
- SIMD
- Soft output Viterbi algorithm
- Systematic code
- Telecommunication
- Transfer function
- Trellis (graph)
- Turbo code
- Turbo codes
- Viterbi algorithm
- VLSI
- Voyager program
- XOR gate
- Z-transform
- SameAs
- Codice convoluzionale
- Codi convolucional
- Código convolucional
- Código convolucional
- Faltningskodare
- Faltungscode
- Kod splotowy
- Konvoluční kód
- Konvolutsioonkood
- m.0b6xt
- Mã xoắn
- Q1395022
- QMiB
- Згорткове кодування
- Свёрточный код
- קוד קונבולוציה
- کد کانولوشنال
- 卷积码
- 畳み込み符号
- SeeAlso
- Punctured code
- Trellis modulation
- Viterbi algorithm
- Subject
- Category:Error detection and correction
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- Convolutional code?oldid=1100051594&ns=0
- WikiPageLength
- 24896
- Wikipage page ID
- 40962
- Wikipage revision ID
- 1100051594
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- 3
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