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Title: Concatenated Spatially Coupled LDPC Codes with Sliding Window Decoding for Joint Source-Channel Coding
In this paper, a method for joint source-channel coding (JSCC) based on concatenated spatially coupled low-density parity-check (SC-LDPC) codes is investigated. A construction consisting of two SC-LDPC codes is proposed: one for source coding and the other for channel coding, with a joint belief propagation-based decoder. Also, a novel windowed decoding (WD) scheme is presented with significantly reduced latency and complexity requirements. The asymptotic behavior for various graph node degrees is analyzed using a protograph-based Extrinsic Information Transfer (EXIT) chart analysis for both LDPC block codes with block decoding and for SC-LDPC codes with the WD scheme, showing robust performance for concatenated SC-LDPC codes. Simulation results show a notable performance improvement compared to existing state-of-the-art JSCC schemes based on LDPC codes with comparable latency and complexity constraints.
Authors:
;
Award ID(s):
1757207 1914635
Publication Date:
NSF-PAR ID:
10304250
Journal Name:
IEEE Transactions on Communications
ISSN:
0090-6778
Sponsoring Org:
National Science Foundation
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