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Construction of Protograph LDPC Codes with Linear Minimum DistanceA construction method for protograph-based LDPC codes that simultaneously achieve low iterative decoding threshold and linear minimum distance is proposed. We start with a high-rate protograph LDPC code with variable node degrees of at least 3. Lower rate codes are obtained by splitting check nodes and connecting them by degree-2 nodes. This guarantees the linear minimum distance property for the lower-rate codes. Excluding checks connected to degree-1 nodes, we show that the number of degree-2 nodes should be at most one less than the number of checks for the protograph LDPC code to have linear minimum distance. Iterative decoding thresholds are obtained by using the reciprocal channel approximation. Thresholds are lowered by using either precoding or at least one very high-degree node in the base protograph. A family of high- to low-rate codes with minimum distance linearly increasing in block size and with capacity-approaching performance thresholds is presented. FPGA simulation results for a few example codes show that the proposed codes perform as predicted.
Document ID
20070011734
Document Type
Conference Paper
External Source(s)
Authors
Divsalar, Dariush (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Dolinar, Sam (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Jones, Christopher (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
August 23, 2013
Publication Date
July 9, 2006
Subject Category
Computer Programming and Software
Meeting Information
IEEE International Symposium on Information Theory(Seattle, WA)
Distribution Limits
Public
Copyright
Other
Keywords
Low-density parity-check (LDPC)