Sparse decoding of low density parity check codes using margin propagation

Ming Gu, Kiran Misra, Hayder Radha, Shantanu Chakrabartty

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

8 Scopus citations


One of the key factors underlying the popularity of Low-density parity-check (LDPC) code is its iterative decoding algorithm that is amenable to efficient hardware implementation. Even though different variants of LDPC iterative decoding algorithms have been studied for its error-correcting properties, an analytical basis for evaluating energy efficiency of LDPC decoders has not been reported. In this paper, we present a framework of a parameterized LDPC decoding algorithm that can be optimized to produce sparse representation of communication messages used in iterative decoding. The sparsity of messages is determined by its differential entropy and has been used as a theoretical metric for determining the energy efficiency of an iterative LDPC decoder. At the core of the proposed algorithm is margin propagation (MP) which approximates the log-sum-exp function used in conventional sum-product (SP) decoders by a piecewise linear (PWL) function. Using Monte-Carlo simulations, we demonstrate that the MP decoding leads to a significant reduction in message entropy compared to a conventional SP decoder, while incurring a negligible performance penalty (less than 0.03dB). The proposed work therefore lays the foundation for design of parameterized LDPC decoders whose bit-errorrate performance can be effectively traded-off with respect to different energy efficiency constraints as required by different set of applications.

Original languageEnglish
Title of host publicationGLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference
StatePublished - 2009
Event2009 IEEE Global Telecommunications Conference, GLOBECOM 2009 - Honolulu, HI, United States
Duration: Nov 30 2009Dec 4 2009

Publication series

NameGLOBECOM - IEEE Global Telecommunications Conference


Conference2009 IEEE Global Telecommunications Conference, GLOBECOM 2009
Country/TerritoryUnited States
CityHonolulu, HI


  • Low density parity check codes
  • Margin propagation


Dive into the research topics of 'Sparse decoding of low density parity check codes using margin propagation'. Together they form a unique fingerprint.

Cite this