Spatially-Coupled LDPC Codes for Decode-and-Forward Relaying of Two Correlated Sources over the BEC
Artikel i vetenskaplig tidskrift, 2014

We present a decode-and-forward transmission scheme based on spatially-coupled low-density parity-check (SC-LDPC) codes for a network consisting of two (possibly correlated) sources, one relay, and one destination. The links between the nodes are modeled as binary erasure channels. Joint source-channel coding with joint channel decoding is used to exploit the correlation. The relay performs network coding. We derive analytical bounds on the achievable rates for the binary erasure time-division multiple-access relay channel with correlated sources. We then design bilayer SC-LDPC codes and analyze their asymptotic performance for this scenario. We prove analytically that the proposed coding scheme achieves the theoretical limit for symmetric channel conditions and uncorrelated sources. Using density evolution, we furthermore demonstrate that our scheme approaches the theoretical limit also for non-symmetric channel conditions and when the sources are correlated, and we observe the threshold saturation effect that is typical for spatially-coupled systems. Finally, we give simulation results for large block lengths, which validate the DE analysis.

relay channel

cooperative communications

distributed coding

threshold saturation


Binary erasure channel

spatially-coupled low-density parity-check codes

correlated sources


S. Schwandter

Ametek Inc.

Alexandre Graell i Amat

Signaler och system, Kommunikationssystem, informationsteori och antenner, Kommunikationssystem

G. Matz

Technische Universitat Wien

IEEE Transactions on Communications

0090-6778 (ISSN)

Vol. 62 1324-1337 6750419


Elektroteknik och elektronik