基于优化比特分配的有限反馈干扰对齐方案  

Interference alignment based on optimizing bit allocation with limited feedback in interfering MIMO-MAC networks

作　　者：谢显中[1] 李丹[1] 雷维嘉[1] 张森林[1] 

机构地区：[1]重庆邮电大学个人通信研究所,重庆400065

出　　处：《通信学报》2017年第11期1-12,共12页Journal on Communications

基　　金：国家自然科学基金资助项目(No.61271259;No.61301123;No.61471076);重庆市教委科学技术研究基金资助项目(No.KJ130536);长江学者和创新团队发展计划基金资助项目(No.IRT1299);重庆市科委重点实验室专项基金资助项目(No.CSTC2012zbsy006);安徽省教育厅基金资助项目(No.AQKJ2015B008)~~

摘　　要：针对多小区MIMO上行链路中有限反馈干扰对齐方案的不足,给出一种基于优化比特分配的有限反馈干扰对齐方案。为克服低SNR时频谱效率的损失,通过最大化用户的信号功率与泄露到其他小区的干扰与噪声功率之和的比值来求预编码,基于最大化每个数据流的信干噪比来设计干扰抑制矩阵。进一步,为克服传统比特分配方案反馈比特利用度不高的问题,给出一种新颖的比特分配方案来改善比特分布,减小了量化误差的影响。仿真实验表明,本算法能有效减少量化误差对系统性能的影响并显著提高系统的比特利用率,使有限反馈CSI时的干扰对齐性能得以提升。A novel limited feedback for interference alignment algorithm was proposed based on the disadvantages of traditional limited feedback interference alignment schemes for MIMO uplink. Unlike the traditional linear interfe-rence alignment, an iterative scheme was presented. The pre-coder was designed through maximizing the target signal to the interference leakage and noise ratio, and interference suppression matrix was designed by maximizing the signal to interference plus noise ratio for each data stream, which can come over rate loss in low SNR. In addition, the bit allocation of traditional limited feedback schemes were based on the mean of interference leakage, which were not perfect and make the total number of the effective bits less than the bits provided by system. Thus, a novel bit alloca-tion scheme was provided that improving bit utilize and decreasing quantization error. Theoretical analysis and simu-lation experiments show that compare to the existed classical algorithms, the algorithm was a stepwise enhancement of signal quality for iterative search in perfect CSI which was better than linear algorithm and has a larger space with no need for strictly align interference in limited feedback CSI which reduces the influence of quantization error more. The effective bit distribution and bit utilization are improved by bit allocation, resulting in improved performance in li-mited feedback.

关 键 词：干扰对齐 有限反馈 比特分配 量化误差 比特利用度 

分 类 号：TN929.53[电子电信—通信与信息系统]