BCJR algorithm - Revision history

Fluxjupyter: Added full name and trellis link

2024-06-21T21:11:48Z

Added full name and trellis link

← Previous revision		Revision as of 21:11, 21 June 2024
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	{{short description\|Error correction algorithm}}		{{short description\|Error correction algorithm}}
	The '''BCJR algorithm''' is an [[algorithm]] for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">{{cite journal \|first1=L. \|last1=Bahl \|first2=J. \|last2=Cocke \|first3=F. \|last3=Jelinek \|first4=J. \|last4=Raviv \|title=Optimal Decoding of Linear Codes for minimizing symbol error rate \|journal=IEEE Transactions on Information Theory \|volume=20 \|issue=2 \|pages=284–7 \|date=March 1974 \|doi=10.1109/TIT.1974.1055186 }}</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes, including [[turbo ~~code~~]]s and [[low-density parity-check ~~code~~]]s.		The '''Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm''' is an [[algorithm]] for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on [[Trellis_(graph)\|trellises]] (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">{{cite journal \|first1=L. \|last1=Bahl \|first2=J. \|last2=Cocke \|first3=F. \|last3=Jelinek \|first4=J. \|last4=Raviv \|title=Optimal Decoding of Linear Codes for minimizing symbol error rate \|journal=IEEE Transactions on Information Theory \|volume=20 \|issue=2 \|pages=284–7 \|date=March 1974 \|doi=10.1109/TIT.1974.1055186 }}</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes, including [[turbo codes]] and [[low-density parity-check codes]].

	==Steps involved==		==Steps involved==
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	===SBGT BCJR===		===SBGT BCJR===
	Berrou, Glavieux and Thitimajshima simplification.<ref>{{cite journal \|first1=Sichun \|last1=Wang \|first2=François \|last2=Patenaude \|title=A Systematic Approach to Modified BCJR MAP Algorithms for Convolutional Codes \|journal=EURASIP Journal on Applied Signal Processing \|volume=2006 \|issue= \|pages=95360 \|date= 2006\|doi=10.1155/ASP/2006/95360 \|bibcode=2006EJASP2006..242W \|doi-access=free }}</ref>		Berrou, Glavieux and Thitimajshima simplification.<ref name="sichun2006">{{cite journal \|first1=Sichun \|last1=Wang \|first2=François \|last2=Patenaude \|title=A Systematic Approach to Modified BCJR MAP Algorithms for Convolutional Codes \|journal=EURASIP Journal on Applied Signal Processing \|volume=2006 \|issue= \|pages=95360 \|date= 2006\|doi=10.1155/ASP/2006/95360 \|bibcode=2006EJASP2006..242W \|doi-access=free }}</ref>

	===Log-Map BCJR===		===Log-Map BCJR===

OAbot: Open access bot: doi updated in citation with #oabot.

2023-11-27T22:52:32Z

Open access bot: doi updated in citation with #oabot.

← Previous revision		Revision as of 22:52, 27 November 2023
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	===Log-Map BCJR===		===Log-Map BCJR===
	{{Expand section\|date=September 2022}}		{{Expand section\|date=September 2022}}
	<ref>{{cite journal \|first1=P. \|last1=Robertson \|first2=P. \|last2=Hoeher \|first3=E. \|last3=Villebrun \|title=Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding \|journal=European Transactions on Telecommunications \|volume=8 \|issue=2 \|pages=119–125 \|date=1997 \|doi=10.1002/ett.4460080202 }}		<ref>{{cite journal \|first1=P. \|last1=Robertson \|first2=P. \|last2=Hoeher \|first3=E. \|last3=Villebrun \|title=Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding \|journal=European Transactions on Telecommunications \|volume=8 \|issue=2 \|pages=119–125 \|date=1997 \|doi=10.1002/ett.4460080202 \|doi-access=free }}
	</ref>		</ref>

RDBrown: →cite journal | Alter: date. Add: doi-access, bibcode, authors 1-1. Removed parameters. Some additions/deletions were parameter name changes. | Use this tool. Report bugs. | #UCB_Gadget

2023-09-23T08:47:25Z

→cite journal | Alter: date. Add: doi-access, bibcode, authors 1-1. Removed parameters. Some additions/deletions were parameter name changes. | Use this tool. Report bugs. | #UCB_Gadget

← Previous revision		Revision as of 08:47, 23 September 2023
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	{{short description\|Error correction algorithm}}		{{short description\|Error correction algorithm}}
	The '''BCJR algorithm''' is an [[algorithm]] for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.~~Jelinek,~~ ~~and~~ J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, ~~vol.~~ ~~IT-20(~~2), ~~pp. 284-287,~~ March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes, including [[turbo code]]s and [[low-density parity-check code]]s.		The '''BCJR algorithm''' is an [[algorithm]] for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">{{cite journal \|first1=L. \|last1=Bahl \|first2=J. \|last2=Cocke \|first3=F. \|last3=Jelinek \|first4=J. \|last4=Raviv \|title=Optimal Decoding of Linear Codes for minimizing symbol error rate \|journal=IEEE Transactions on Information Theory \|volume=20 \|issue=2 \|pages=284–7 \|date=March 1974 \|doi=10.1109/TIT.1974.1055186 }}</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes, including [[turbo code]]s and [[low-density parity-check code]]s.

	==Steps involved==		==Steps involved==
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	===SBGT BCJR===		===SBGT BCJR===
	Berrou, Glavieux and Thitimajshima simplification.<ref>Sichun Wang ~~and~~ François Patenaude, "A Systematic Approach to Modified BCJR MAP Algorithms for Convolutional Codes," ''EURASIP Journal on Applied Signal Processing~~'', vol.~~ 2006, ~~Article ID~~ 95360, ~~15 pages,~~ 2006~~. {{~~doi\|10.1155/ASP/2006/95360}}</ref>		Berrou, Glavieux and Thitimajshima simplification.<ref>{{cite journal \|first1=Sichun \|last1=Wang \|first2=François \|last2=Patenaude \|title=A Systematic Approach to Modified BCJR MAP Algorithms for Convolutional Codes \|journal=EURASIP Journal on Applied Signal Processing \|volume=2006 \|issue= \|pages=95360 \|date= 2006\|doi=10.1155/ASP/2006/95360 \|bibcode=2006EJASP2006..242W \|doi-access=free }}</ref>

	===Log-Map BCJR===		===Log-Map BCJR===
	{{Expand section\|date=September 2022}}		{{Expand section\|date=September 2022}}
	<ref>P. Robertson, P. Hoeher ~~and~~ E. Villebrun, "Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding", European Transactions on Telecommunications~~, Vol.~~ 8, 1997.		<ref>{{cite journal \|first1=P. \|last1=Robertson \|first2=P. \|last2=Hoeher \|first3=E. \|last3=Villebrun \|title=Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding \|journal=European Transactions on Telecommunications \|volume=8 \|issue=2 \|pages=119–125 \|date=1997 \|doi=10.1002/ett.4460080202 }}
	</ref>		</ref>

TypistMonkey: Added section needs expansion. Added a few links. Inserted comma.

2022-09-26T03:33:40Z

Added section needs expansion. Added a few links. Inserted comma.

← Previous revision		Revision as of 03:33, 26 September 2022
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	{{short description\|Error correction algorithm}}		{{short description\|Error correction algorithm}}
	The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.		The '''BCJR algorithm''' is an [[algorithm]] for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes, including [[turbo code]]s and [[low-density parity-check code]]s.

	==Steps involved==		==Steps involved==
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	* Compute forward probabilities <math>\alpha</math>		* Compute forward probabilities <math>\alpha</math>
	* Compute backward probabilities <math>\beta</math>		* Compute backward probabilities <math>\beta</math>
	* Compute smoothed probabilities based on other information (i.e. noise variance for [[AWGN]], bit crossover probability for [[binary symmetric channel]])		* Compute smoothed probabilities based on other information (i.e. [[noise variance]] for [[AWGN]], [[bit crossover probability]] for [[binary symmetric channel]])

	==Variations==		==Variations==
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	===Log-Map BCJR===		===Log-Map BCJR===
			{{Expand section\|date=September 2022}}
	<ref>P. Robertson, P. Hoeher and E. Villebrun, "Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding", European Transactions on Telecommunications, Vol. 8, 1997.		<ref>P. Robertson, P. Hoeher and E. Villebrun, "Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding", European Transactions on Telecommunications, Vol. 8, 1997.
	</ref>		</ref>

PamD: stub-sort

2022-03-25T18:41:15Z

stub-sort

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	{{DEFAULTSORT:Bcjr Algorithm}}		{{DEFAULTSORT:Bcjr Algorithm}}
	[[Category:Error detection and correction]]		[[Category:Error detection and correction]]

			{{algorithm-stub}}

PamD: Undid revision 1079159918 by Marcusmueller ettus (talk) see WP:ORDER: stub tag goes at end

2022-03-25T18:39:30Z

Undid revision 1079159918 by Marcusmueller ettus (talk) see WP:ORDER: stub tag goes at end

← Previous revision		Revision as of 18:39, 25 March 2022
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	{{Stub}}
	{{short description\|Error correction algorithm}}		{{short description\|Error correction algorithm}}
	The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.		The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.

MüllerMarcus: This article is mostly just a stub, with an unsorted collection of reference to partially very specific subtopics or implementations. A reader new to the topic should be warned of that!

2022-03-25T09:42:50Z

This article is mostly just a stub, with an unsorted collection of reference to partially very specific subtopics or implementations. A reader new to the topic should be warned of that!

← Previous revision		Revision as of 09:42, 25 March 2022
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			{{Stub}}
	{{short description\|Error correction algorithm}}		{{short description\|Error correction algorithm}}
	The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.		The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.

A bit iffy: + short description

2021-11-28T12:25:48Z

+ short description

← Previous revision		Revision as of 12:25, 28 November 2021
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			{{short description\|Error correction algorithm}}

	The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.		The '''BCJR algorithm''' is an algorithm for [[maximum a posteriori]] decoding of [[error correcting code]]s defined on trellises (principally [[convolutional code]]s). The algorithm is named after its inventors: Bahl, Cocke, [[Frederick Jelinek\|Jelinek]] and Raviv.<ref name="bcjr">L.Bahl, J.Cocke, F.Jelinek, and J.Raviv, "Optimal Decoding of Linear Codes for minimizing symbol error rate", IEEE Transactions on Information Theory, vol. IT-20(2), pp. 284-287, March 1974.</ref> This algorithm is critical to modern iteratively-decoded error-correcting codes including [[turbo code]]s and [[low-density parity-check code]]s.

Neutronstar2: /* Implementations */ updated link

2020-09-02T12:55:56Z

Implementations: updated link

← Previous revision		Revision as of 12:55, 2 September 2020
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	==Implementations==		==Implementations==
	* [http://~~susalib~~.org/ Susa] framework implements BCJR algorithm for [[forward error correction]] codes and channel equalization in C++.		* [http://libsusa.org/ Susa] framework implements BCJR algorithm for [[forward error correction]] codes and channel equalization in C++.

	==See also==		==See also==

212.39.89.100: /* Max-Log-Map BCJR */

2018-02-07T16:57:30Z

Max-Log-Map BCJR

← Previous revision		Revision as of 16:57, 7 February 2018
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	<ref>P. Robertson, P. Hoeher and E. Villebrun, "Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding", European Transactions on Telecommunications, Vol. 8, 1997.		<ref>P. Robertson, P. Hoeher and E. Villebrun, "Optimal and Sub-Optimal Maximum A Posteriori Algorithms Suitable for Turbo Decoding", European Transactions on Telecommunications, Vol. 8, 1997.
	</ref>		</ref>

	===Max-Log-Map BCJR ===

	==Implementations==		==Implementations==