【摘要】 WIMAX标准下的LDPC码采用准循环编码方式,其译码多为和积(SP)译码算法。为了进一步降低译码复杂度,通过大量仿真分析获得最优乘性因子的值,并推导出近似线性公式,提出了一种改进型的归一化最小和(MNMS)算法。在此基础上,与校验节点匹配(CNM)算法相结合,进一步提高译码性能。仿真结果表明,这种新算法相比归一化最小和(NMS)算法、抵消最小和(OMS)算法、校验节点匹配(CNM)算法,其译码性能有明显改善,性能几乎接近和积(SP)译码算法。更多还原

【Abstract】 WIMAX standard LDPC is based on quasi-cyclic encoding,and the decoding usually uses the sum-product decoding algorithm.In order to further reduce decoding complexity,a novel modified normalized min-sum(NMS) algorithm is proposed in this paper.The optimal multiplicative factor is obtained by a lot of simulation samples and analyses,and the approximate linear formula is deduced as well.On the basis of it,combining with the check node degree-matched algorithm,the decoding performance is improved further.Simulation results indicate that the proposed novel algorithm improves the decoding performance greatly compared with the NMS algorithm,the offset min-sum(OMS) algorithm and check node degree-matched(CNM) algorithm,and the BER is very close to the sum-product algorithm.更多还原