LDPC Code Decoding Simulation Using Log-BP Algorithm

This document provides a simulation program for LDPC code decoding using the Log-BP (Logarithmic Belief Propagation) algorithm. The program performs simulations under various Signal-to-Noise Ratio (SNR) conditions and generates statistical charts for Bit Error Rate (BER) and Packet Error Rate (PER). To enhance usability and performance, the implementation is available in both MATLAB and C (via C-MEX interface) versions. The MATLAB version offers clear algorithmic implementation for educational purposes, while the C-MEX version provides optimized computational efficiency for large-scale simulations. Each code section includes detailed explanations and comprehensive comments covering key aspects such as message initialization, iterative update rules, stopping criteria, and result visualization. These annotations help users better understand the program's functionality and implementation details, including the log-domain message passing mechanism and convergence properties. The modified document aims to meet your requirements for both theoretical understanding and practical implementation.