Non-systematic LDPC codes via scrambling and splitting

Amira Alloum, Joseph Boutros, Gil I. Shamir, Li Wang

Research output: Chapter in Book/Report/Conference proceedingConference contribution

12 Citations (Scopus)

Abstract

We consider design of non-systematic low-density parity-check (LDPC) codes for channel decoding of redundant sequences. We demonstrate that in the presence of source redundancy in channel coded sequences there may be a significant advantage to well designed non-systematic channel encoding over systematic encoding. In particular, we study methods we recently proposed for designing non-systematic LDPC codes by scrambling or splitting redundant data bits into coded bits. These methods consist of cascading a sparse matrix or an inverse of a sparse matrix with an LDPC code. We propose a method to perform density evolution on splitting based LDPC codes, and show that splitting based LDPC codes achieve better gains in the presence of redundancy than other known codes, including MacKay-Neal (MN) codes, without significant loss even if the data contains no redundancy. Using density evolution, we show that for independently identically distributed (i.i.d.) nonuniform (redundant) sequences, splitting based non-systematic codes can theoretically achieve very good performance.

Original languageEnglish
Title of host publication43rd Annual Allerton Conference on Communication, Control and Computing 2005
PublisherUniversity of Illinois at Urbana-Champaign, Coordinated Science Laboratory and Department of Computer and Electrical Engineering
Pages1879-1888
Number of pages10
Volume4
ISBN (Electronic)9781604234916
Publication statusPublished - 1 Jan 2005
Externally publishedYes
Event43rd Annual Allerton Conference on Communication, Control and Computing 2005 - Monticello, United States
Duration: 28 Sep 200530 Sep 2005

Other

Other43rd Annual Allerton Conference on Communication, Control and Computing 2005
CountryUnited States
CityMonticello
Period28/9/0530/9/05

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ASJC Scopus subject areas

  • Computer Networks and Communications
  • Computer Science Applications

Cite this

Alloum, A., Boutros, J., Shamir, G. I., & Wang, L. (2005). Non-systematic LDPC codes via scrambling and splitting. In 43rd Annual Allerton Conference on Communication, Control and Computing 2005 (Vol. 4, pp. 1879-1888). University of Illinois at Urbana-Champaign, Coordinated Science Laboratory and Department of Computer and Electrical Engineering.