Encoding Methods for Random Low-Density Parity-Check Codes

DOI: 10.21293/1818-0442-2026-29-2-64-73

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Abstract: Relevance. The development and investigation of encoding methods for random low-density parity-check (LDPC) codes is an important task in the design of high-speed communication systems, since different codeword generation algorithms differ significantly in computational cost and implementation requirements. Purpose of the study. Comparative analysis of encoding methods for LDPC-codes defined by random sparse parity-check matrices, with an assessment of their computational complexity and practical performance. Methods. The study employs methods of linear algebra, analytical estimation of computational complexity, simulation modeling, and the Monte Carlo method. The encoding approaches under study include Neal's method, algorithms based on LU and LUP-decompositions, transformation of the parity-check matrix to row-echelon form, as well as lower and approximate lower triangulation methods. Scientific novelty. A comparative study of encoding methods for random LDPC codes was carried out, including a joint assessment of their analytical computational complexity and software implementation time under identical initial conditions. Results. Differences in the growth patterns of computational costs among the considered methods as the size of the parity-check matrix increases were identified. It was shown that Neal's method, LU decomposition, and the method based on transformation to row-echelon form require fewer arithmetic operations, whereas the results of software simulations depend significantly on the implementation approach and the optimization capabilities for matrix operations in MatLab. Practical significance. The obtained results can be used to select encoding algorithms for random LDPC-codes and developing software and hardware encoders for high-speed communication systems.

Keywords: LDPC, low-density parity-check codes, random matrices, error-correcting coding, computational complexity

For citation:
Kravchenko A. N., Pokamestov D. A. Encoding Methods for Random Low-Density Parity-Check Codes. Doklady Tomskogo gosudarstvennogo universiteta sistem upravleniya i radioelektroniki, 2026, vol. 29, no. 2, pp. 64–73. DOI: 10.21293/1818-0442-2026-29-2-64-73

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