Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Techniques and Architectures for Hazard-Free Semi-Parallel Decoding of LDPC Codes | Hindawi Publishing Corporation EURASIP Journal on Embedded Systems Volume 2009 Article ID 723465 15 pages doi 2009 723465 Research Article Techniques and Architectures for Hazard-Free Semi-Parallel Decoding of LDPC Codes Massimo Rovini Giuseppe Gentile Francesco Rossi and Luca Fanucci Department of Information Engineering University of Pisa Via G. Caruso 16 56122 Pisa Italy Correspondence should be addressed to Massimo Rovini Received 4 March 2009 Revised 18 May 2009 Accepted 27 July 2009 Recommended by Markus Rupp The layered decoding algorithm has recently been proposed as an efficient means for the decoding of low-density parity-check LDPC codes thanks to the remarkable improvement in the convergence speed 2x of the decoding process. However pipelined semi-parallel decoders suffer from violations or hazards between consecutive updates which not only violate the layered principle but also enforce the loops in the code thus spoiling the error correction performance. This paper describes three different techniques to properly reschedule the decoding updates based on the careful insertion of idle cycles to prevent the hazards of the pipeline mechanism. Also different semi-parallel architectures of a layered LDPC decoder suitable for use with such techniques are analyzed. Then taking the LDPC codes for the wireless local area network IEEE as a case study a detailed analysis of the performance attained with the proposed techniques and architectures is reported and results of the logic synthesis on a 65 nm low-power CMOS technology are shown. Copyright 2009 Massimo Rovini et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction Improving the reliability of data transmission over noisy channels is the key issue of modern communication systems and .
