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Design of two-edge type LDPC codes with high rate and short length

Mi Xiao

Published Jan 1, 2014• 0 citations

Abstract

It is a challenge to design high-rate LDPC codes,especially with short length. Two-edge type LDPC( TET-LDPC) codes proposed recently have been shown to possess better performance than conventional LDPC codes at high rate. In this paper,structural advantages of TET-LDPC codes are investigated. Based on the advantages,a novel approach to design TET-LDPC codes at high rate is proposed,which aims to improve the performance by choosing a suitable degree for punctured variable nodes and optimizing the connections between variable nodes and check nodes. The simulation results show that the short-length high-rate TET-LDPC codes designed by the proposed approach can not only outperform conventional LDPC codes and conventional TET-LDPC codes,but also have lower error floors.

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