CAJ | 학술논문

采用经典LLR BP算法对低密度奇偶校验（ Low Density Parity Check， LDPC）码译码时，译码复杂度非常高，主要表现在译码时迭代次数过多和每次循环时校验节点的计算复杂度过高。基于以上问题提出一种新的改进型LLR BP译码算法，自适应地实时监控译码是否稳定来降低在低信噪比条件下的译码迭代次数，同时采用函数逼近的方法降低每次循环时校验节点的计算复杂度。仿真结果表明，该算法在译码性能损失不大的情况下可大幅降低LDPC码的译码复杂度。
채용경전LLR BP산법대저밀도기우교험（ Low Density Parity Check， LDPC）마역마시，역마복잡도비상고，주요표현재역마시질대차수과다화매차순배시교험절점적계산복잡도과고。기우이상문제제출일충신적개진형LLR BP역마산법，자괄응지실시감공역마시부은정래강저재저신조비조건하적역마질대차수，동시채용함수핍근적방법강저매차순배시교험절점적계산복잡도。방진결과표명，해산법재역마성능손실불대적정황하가대폭강저LDPC마적역마복잡도。
Classical LLR BP algorithm to decode LDPC involves high complexitybecause of iterations and calculation complexity of horizontal directions in every iteration process. This paper proposes a new modified LLR BP algorithm to monitor whether decoding output is stable or not to decrease iteration times in low signal noise rate.At the same time,Taylor function approximation is adopted to reduce calculation complexity at check codes. Simulations reveal that this proposed method can reduce decode complexity widely for LDPC in the condition of a small decoding performance loss.