级联编码MIMO系统的迭代检测算法

摘要

An outer decoder feedback⁃iterative detection and decoding ( ODF⁃IDD) algorithm is proposed for BCH⁃LDPC coded MIMO systems. Based on the iterative detection and decoding ( IDD) algorithm, a feedback after outer hard⁃decision decoder is added. The feedback hard⁃decision information from the BCH decoder is processed in the MIMO detector and used to update the detecting list after the mapping treatment, thus the computational complexity of the iterative detection decoding algorithm can be reduced by this step. Some of the initial probabilities for some parts of LDPC decoder are calculated directly using the feedback information from the outer decoder, which makes the soft information more reliable and therefore improves the system performance. The simulation results showed that the proposed algorithm can decrease the average number of detection times by 57.1% per frame and thus reduce the computation complexity of the receiver. Meanwhile, the proposed algorithm has a performance gain of 0. 2 dB at least due to the feedback from the BCH decoder.%针对BCH⁃LDPC级联编码的MIMO系统，提出一种外码译码反馈联合迭代检测译码算法。该算法在迭代检测译码结构的基础上，引入外码硬判决译码反馈。 MIMO检测器利用反馈的硬判决信息，经过映射处理后用于更新检测器的检测列表，以减小迭代检测译码算法的运算量。同时，利用外码译码结果直接计算部分 LDPC码译码初始信息，提高软信息的可靠性，从而提高系统性能。仿真结果表明，与迭代检测译码算法相比，所提算法能够使处理一帧数据时的平均检测次数减少57．1％，从而降低算法运算量。同时由于外码译码反馈的引入，所提算法至少能够获得0．2 dB性能增益。