BICM系统中一种低复杂度的迭代解映射算法  

Low complexity iterative demapping algorithm in BICM systems

作　　者：马卓[1] 杜栓义[1] 王新梅[1] 

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071

出　　处：《西安电子科技大学学报》2011年第2期42-46,共5页Journal of Xidian University

基　　金：国家973计划资助项目(2010CB328300);国家自然科学基金资助项目(U0635003)

摘　　要：比特交织编码调制（BICM）系统中迭代解映射算法具有与调制阶数和星座点数的乘积相关的计算复杂度,不利于实时应用.为了降低其复杂度,针对采用LDPC编码的BICM系统,提出了一种利用硬判决结果进行反馈的简化迭代算法,并在无反馈信息的首次迭代时采用了基于判决边界的软信息算法.仿真结果表明,算法在高斯白噪声下与软信息迭代算法的性能只有0.04~0.06 dB的差距,但其计算复杂度仅与调制阶数相关,利于实际应用.The complexity of the iterative Demapping algorithm in Bit-Interleaved Coded Modulation systems is related to the product of the order of modulation and the constellation points number,so that it is not suitable for real-time applications.To reduce its complexity,we give a shortcut calculation based on the Hard Decision Feedback for the BICM system using LDPC codes.A soft information calculation algorithm based on the decision boundary is used in the first iteration,where no feedback information is available to be used.Simulation result shows that the BWE performance of the algorithm proposed in the AWGN channel has only a distance of 0.04～0.06dB from the soft information iteration algorithm.On the other hand,the calculation complexity of this algorithm is only related to the order of the modulation,which is more suitable for application.

关 键 词：比特交织编码调制 迭代解映射 判决反馈 信道编码 低密度奇偶校验码 

分 类 号：TN911.2[电子电信—通信与信息系统]