MIMO信道树形矢量量化编码反馈方法  

A low-rate feedback scheme using tree-structured vector quantization and encoding for MIMO channels

作　　者：丁律[1] 许威[1] 江彬[1] 高西奇[1] 

机构地区：[1]东南大学移动通信国家重点实验室,南京210096

出　　处：《高技术通讯》2009年第9期891-896,共6页Chinese High Technology Letters

基　　金：国家自然科学基金(60572072;60496311);863计划(2006AA01Z264);973计划(2007CB310603);国家博士点基金(20060286016)资助项目。

摘　　要：为了进一步降低有限反馈系统的反馈量,提出了一种多输入多输出(MIMO)信道树形矢量量化编码反馈方法。对于具有时间相关性的信道,首先统计出在已知当前码字的条件下下一个码字出现的条件概率,然后根据条件概率进行条件熵编码,编码结果反馈到输入端进行波束成形。该方法利用树形码本提高最优码字的搜索效率,减少计算量;利用信道的时间相关性提高编码效率,降低反馈量。仿真结果表明,在具有时间相关性的信道中,采用所提方法能以较少的计算量和较低的反馈量获取与传统方案相近的系统性能。In order to further reduce the feedback amount in limited feedback systems, this paper proposes an efficient feedback scheme using tree-structured vector quantization and encoding for multiple input multiple output （MIMO） channels. When a channel is time correlated, the scheme calculates the conditional probability of each codeword first, then performs entropy coding based on the conditional probability, and finally, sends the coding results into the transmitter for beamforming through the limited feedback channel. By utilizing the tree-structured codebook, it can find the optimum codeword with a low computational complexity. Furthermore, by exploiting the channel correlation information in the time domain, it can improve the coding efficiency and shorten the amount of feedback information. The simulation results show that in time-correlated channels the new approach can obtain the same performance as the conventional feedback scheme while the computational complexity and feedback information are significantly reduced.

关 键 词：多输入多输出(MIMO) 有限反馈 波束成形 树形码本 哈夫曼编码 

分 类 号：TN919.3[电子电信—通信与信息系统]