相关衰落信道MIMO STBC分集增益与多用户自适应OFDMA研究

首先沿用经典的分集增益特性分析了在已知与未知多输入多输出（MIMO）信道状况的条件下空时分组码（STBC）接收机的性能,从而揭示了相关衰落下信道矩阵的秩和特征值扩展对分集增益与编码增益等极其重要的影响;接着提出了一种与多天线STBC等效的单发单收（SISO）模型,将复杂的分集增益指标转换为直观的SNR指标,明确表示出接收机SNR与信道相关矩阵之间的关系,并以此为基础,提出一种实用的多用户MIMO-OFDM系统STBC编码优化的子载波资源分配OFDMA方法,进一步提高频谱效率与系统性能.

Diversity of MIMO STBC and adaptive OFDMA under correlated fading channel

A spatial-temporal diversity theory based on the MIMO STBC system under the correlated fading channel was presented. It was pointed out that the performance of the system was deteriorated because of the channel correlation. The traditional method of analyzing diversity gain and coding gain was very complicated, thus an equivalent SISO model for MIMO STBC system was introduced, which depicted the relationship between the SNR and the eigenvalues of the correla-tion channel matrix. Furthermore, an adaptive OFDM access algorithm for multi-users in MIMO-OFDM system was pro-posed. The simulations show the adaptive algorithm has optimal performance and higher spectrum efficiency than FDMA.