New Coupled Codes Constructed by Overlapping Circular SC-LDPC Codes

In this paper, we propose new coupled codes constructed by overlapping circular spatially-coupled low-density parity-check (SC-LDPC) codes, which show better asymptotic and finite-length decoding performance compared to the conventional SC-LDPC codes. The performance improvement comes from the property that the proposed codes effectively split into two separated SC-LDPC codes with shorter chain length during the decoding process. We verify that the property of the proposed codes is valid in asymptotic setting via analysis tools such as the density evolution and the expected graph evolution. Experimental results show that the proposed codes also outperform the conventional SC-LDPC codes in terms of the finite-length performance under belief propagation decoding.