2020/03/19 by Tasdighi, Alireza, Boutillon, Emmanuel · 1 citation
#FOS: Computer and information sciences #FOS: Mathematics #Group Theory (math.GR) #Information Theory (cs.IT) #Number Theory (math.NT)
paper · doi:10.48550/arxiv.2003.08707
This paper proposes a new method of constructing compact fully-connected Quasi-Cyclic Low Density Parity Check (QC-LDPC) codes with girth g = 8, 10, and 12. The originality of the proposed method is to impose constraints on the exponent matrix P to reduce the search space drastically. For a targeted lifting degree of N, the first step of the method is to sieve the integer ring ZN to make a particular sub-group with specific properties to construct the second column of P (the first column being filled with zeros). The remaining columns of P are determined recursively as multiples of the second column by adapting the sequentially multiplied column (SMC) method whereby a controlled greedy search is applied at each step. The codes constructed with the proposed semi-algebraic method show lengths that can be significantly shorter than their best counterparts in the literature.