MIMO系统有限反馈预编码和码本设计研究

多输入多输出（MIMO）技术可以在不增加带宽的条件下，获得分集和复用增益，从而显著提高通信系统的可靠性和传输速率。通过有限反馈预编码技术，MIMO系统的误码性能和速率可以得到相当的提高。本文研究了在发射端无法获得理想信道状态信息时预编码器的误码性能，主要研究内容包括：在平坦块衰落条件下，探讨不同反馈比特数对系统误码率的降低情况，结果显示系统性能会随反馈比特数的增大而提升，但当反馈比特数超过5比特时，进一步增加反馈比特数所带来误码性能提高可忽略；调查了窄带 MIMO 系统天线相关性对预编码误码性能的影响，通过仿真发现在不考虑相关性时，最优的码本算法分别为 Lloyd向量量化算法，而当考虑相关性后，最优的码本算法则为 Grassmann 子空间分组算法；比较了 MIMO 系统各种检测算法的性能，发现基于格基理论的检测算法相比迫零、最小均方检测算法和串行干扰算法可以更大提高预编码器的整体检测性能。关键词多输入多输出有限反馈预编码码本天线相关性多普勒频移检测格基规约7487
Title        Research on Limited Feedback Precoding         and Codebook Designing in MIMO Systems
Abstract
By offering spatial persity and multiplexing gains without
increasing transmission bandwidth, multiple input and multiple output
(MIMO) can improve the reliability and rate of transmission per Hz/s. The
transmission rate and bit error rate (BER) performance of MIMO system are
improved by using limited feedback precoding. In this paper, we focus on
the performance of precoding under non-perfect channel conditions. The
main work is as follows: firstly, we discuss how the number of feedback
bits (NBFs) would affect the system performance, and the result shows that
the BER reduces with the increase of the NFBs when NFBs<5, yet further
increasing the NFBs has no influence on the BER performance; secondly, we
investigate the impact of antenna correlation on BER performance of
precoder, and by simulation, we find that the optimal codebook in
non-correlated channel is the Lloyd codebook whereas the Grassmann
codebook is the best one among Discrete Fourier transform, Grassmann and
Lloyd codebooks in correlated channel; thirdly, the performance of several
detection algorithms are compared, it follows from simulations that the
based-on-lattice-reduction detector performs better than zero forcing,
minimum mean square error, and serial interference cancellation detector.
Keywords    MIMO Limited feedback Precoding Codebook Antenna correlation
Doppler shift Detection Lattice reduction
目   次
1 绪论 . 1
1.1 研究背景    1
1.2 MIMO 系统概述 . 1
1.3 有限反馈技术简介 . 2
1.4 本文主要内容及结构安排 . 3
2 MIMO系统基本理论   5
2.1 无线信道传播特性 . 5
2.2 MIMO 系统信道模型   6
2.3 MIMO 系统容量 . 7
2.4 信号检测技术 .. 7
2.5 仿真结果与分析    9
2.6 本章小结 .. 10
3 MIMO系统有限反馈预编码技术 . 11
3.1 基于信道统计特性的有限反馈技术 . 11
3.2 基于码本的有限反馈预编码技术    12
3.3 天线选择技术 . 19
3.4 仿真结果与分析 .. 20
3.5 本章小结 .. 28 MIMO系统有限反馈预编码和码本设计研究:http://www.youerw.com/tongxin/lunwen_5471.html