Open AccessRate‐compatible spatially coupled LDPC code ensembles based on repeat‐accumulate extensions
Author(s) -
Hou Wei,
Lu Shan,
Cheng Jun
Publication year - 2016
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2015.1031
Subject(s) - low density parity check code , computer science , code (set theory) , algorithm , theoretical computer science , decoding methods , programming language , set (abstract data type)
A family of rate‐compatible capacity‐approaching codes is obtained by spatially coupling multiple identical copies of rate‐compatible base codes. The base code consists of a given regular low‐density parity‐check (LDPC) code and a parameter‐adjustable repeat‐accumulate (RA) extension. The RA‐extension repeatedly accumulates all of the variable nodes of the given LDPC code by q + 1 times to generate q + 1 blocks of accumulated nodes, in which all of the accumulated variable nodes in the first q blocks and the α ‐fractional accumulated variable nodes in the last block are transmitted. The spatially coupled versions of the base codes, called RA‐extended spatially coupled LDPC (SC‐LDPC) codes, achieve arbitrary rates by simply adjusting parameters q and α , and thus they are rate‐compatible. The potential thresholds of the base code ensembles are calculated to predict the iterative decoding performance of the proposed RA‐extended SC‐LDPC codes. Numerical results and simulations show that the authors’ proposed rate‐compatible codes are capacity‐approaching over binary erasure channels.