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A New PWL Approximation for the “Self-Adjustable Offset Min-Sum” Decoding with a highly Reduced-Complexity

International Journal of Computer Applications
© 2013 by IJCA Journal
Volume 61 - Number 19
Year of Publication: 2013
Abdessalam Ait Madi
Anas Mansouri
Ali Ahaitouf

Abdessalam Ait Madi, Anas Mansouri and Ali Ahaitouf. Article: A New PWL Approximation for the "Self-Adjustable Offset Min-Sum" Decoding with a highly Reduced-Complexity. International Journal of Computer Applications 61(19):1-6, January 2013. Full text available. BibTeX

	author = {Abdessalam Ait Madi and Anas Mansouri and Ali Ahaitouf},
	title = {Article: A New PWL Approximation for the "Self-Adjustable Offset Min-Sum" Decoding with a highly Reduced-Complexity},
	journal = {International Journal of Computer Applications},
	year = {2013},
	volume = {61},
	number = {19},
	pages = {1-6},
	month = {January},
	note = {Full text available}


A new PieceWiseLinear (PWL) function is proposed for the decoding of the Low-Density-Parity-Check (LDPC) code with the Self Adjustable Offset Min-Sum (SAOMS) algorithm. Avoiding the use of the non-linear function f(x) = ln ?? 1 + e??jxj in the adjustable offset factor, this linear approximation greatly simplifies the hardware implementation with a little BER performance loss. The proposed solution is new, useful and is successfully tested on decoding regulars (504, 252) and (8000, 4000) LDPC codes. The corresponding Check Node Processing Unit (CNPU) have been designed, described and simulated using Very High Speed integrated circuits Hardware Description language(VHDL). The synthesis results were obtained using an Altera Quartus II software with cyclone II EP2CF896C6 as the target FPGA device. The designed CNPU is fully parallel and flexible to be used for different block length when a regulars (3, 6) LDPC codes are required.


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