IEEE Information Theory Workshop (ITW)

Explicit constructions for type-1 QC-LDPC codes with girth at least ten

Juhua Wang, Guohua Zhang, Quan Zhou, Yang Yang, Rong Xia Sun

Published Nov 1, 2014• 10 citations

Abstract

From Sidon sequence over ZP, two classes of type-1 (J = 3;L) QC-LDPC codes are explicitly proposed with block length L2P and with girth at least ten. For the first method, any Sidon sequence over ZP(P odd) with cardinality no smaller than L (L odd) corresponds to a class of type-1 (3, L) QC-LDPC codes with girth at least ten. For the second one, any Sidon sequence over ZP(P prime) with cardinality no smaller than L (L arbitrary) corresponds to a class of type-1 (3, L) QC-LDPC codes with girth at least ten. Compared with the method from 3-D lattices, which can also generate type-1 QC-LDPC codes with girth at least ten, the main advantage of the new methods is that the construction process is much simpler, and L is not necessarily a prime integer. Simulation results show that the new type-1 QC-LDPC codes outperform the girth-8 QC-LDPC codes constructed by Sidon sequence or the earliest sequence, and perform almost as well as Bocharova's shortest girth-12 QC-LDPC codes.

DOI: 10.1109/itw.2014.6970869

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