Title
Small weight codewords in LDPC codes defined by (dual) classical generalized quadrangles
Abstract
We find lower bounds on the minimum distance and characterize codewords of small weight in low-density parity check (LDPC) codes defined by (dual) classical generalized quadrangles. We analyze the geometry of the non-singular parabolic quadric in PG(4,q) to find information about the LDPC codes defined by Q (4,q), $${\mathcal{W}(q)}$$ and $${\mathcal{H}(3,q^{2})}$$ . For $${\mathcal{W}(q)}$$ , and $${\mathcal{H}(3,q^{2})}$$ , we are able to describe small weight codewords geometrically. For $${\mathcal{Q}(4,q)}$$ , q odd, and for $${\mathcal{H}(4,q^{2})^{D}}$$ , we improve the best known lower bounds on the minimum distance, again only using geometric arguments. Similar results are also presented for the LDPC codes LU(3,q) given in [Kim, (2004) IEEE Trans. Inform. Theory, Vol. 50: 2378---2388]
Year
DOI
Venue
2007
10.1007/s10623-006-9017-6
Des. Codes Cryptography
Keywords
Field
DocType
LDPC code,Generalized quadrangle,Minimum distance,51E12,94B05
Discrete mathematics,Parity bit,Combinatorics,Low-density parity-check code,Generalized quadrangle,Mathematics,Quadric,Parabola
Journal
Volume
Issue
ISSN
42
1
0925-1022
Citations 
PageRank 
References 
7
0.50
19
Authors
3
Name
Order
Citations
PageRank
Jon-Lark Kim131234.62
Keith E. Mellinger28613.04
Leo Storme319738.07