Vol. 56, Issue 2, pp. 247-256 (2026)

Abstract

The performance of low-density parity-check (LDPC) is severely degraded by the atmospheric turbulence induced consecutive burst errors in free-space optical communication (FSO). Thus, multi-bit random interleaving LDPC (MBI-LDPC) code is proposed to decentralize the consecutive burst errors with computational efficiency. Based on the quasi-stationary characteristics of turbulence channel and stopping set analysis, MBI-LDPC code takes multiple bits as the unit of interleaving. Besides, normalized min-sum algorithm is adopted for the decoding process. Therefore, both burst errors compensation and computational efficiency are achieved. The proposed LDPC code was compared to without LDPC (un-coded), LDPC without interleaving (WOI-LDPC), and single-bit random interleaved LDPC (SBI-LDPC). Simulation results demonstrated that MBI-LDPC code outperformed significantly compared to un-coded, WOI-LDPC, and SBI-LDPC with computational efficiency due to an effective error bits cluster dispersion. Besides, approximately 59.91%, 60.04%, and 59.79% of runtimes were reduced compared to SBI-LDPC scheme in the weak, moderate, and strong turbulence channels.