摘要
研究了频率选择性信道下多天线系统的空间线性发射预编码设计问题。针对有循环前缀的块传输系统,通过理论分析指出,在频率选择性信道下设计空间预编码可以等效成现有的在频域为多个相邻频点设计相同的空间预编码,并可以通过凸优化方法对最优方案进行数值求解。为了降低计算复杂度,提出了一种以信道容量上界最大为目标的次优预编码算法。在进行等功率分配时,这种次优方法退化为现有的特征波束形成(EBF)。针对非块传输系统,分析了EBF算法存在的问题,提出了一种基于串行搜索的EBF算法。仿真分析表明,这种方法在高信噪比下的性能明显优于EBF算法。
The problem of linear spatial precoding design is investigated for multiple-antenna systems in frequency selective channels.For block transmission systems using cyclic prefix,it is shown that the linear spatial precoding design problem is equivalent to design one common spatial precoding for multiple adjacent frequency points,which can be numerically solved by convex optimization.Then a low-complexity suboptimal precoding aimed at maximizing the upper bound of channel capacity is proposed,which degenerates to the existing eigen-beamforming （EBF） when the equal power allocation is used.For non-block transmission systems,the drawbacks of EBF are analyzed.Then a novel algorithm based on successive searching,called successive EBF （SS-EBF）,is proposed,which has a significant performance gain over EBF for high signal-to-noise ratio （SNR）.
出处
《信号处理》
CSCD
北大核心
2010年第2期247-254,共8页
Journal of Signal Processing
基金
国际科技合作项目(No.2008DFA12100)~~
关键词
多天线系统
频率选择性信道
预编码设计
特征波束形成
Multiple antenna systems frequency selective channels precoding design eigen-beamforming
