基于MATLAB的MIMO-OFDMA系统的设计与仿真-毕业论文

本科毕业设计(论文)

题 目: 基于MATLAB的

MIMO-OFDMA系统的设计与仿真

学 院: 信息科学技术学院 专 业: 电子信息工程 班 级: 1208022 学 号: 120802219 学生姓名： 陶静 指导教师: 许艺瀚 职称: 副教授

二○一六年 五 月 十八 日

基于MATLAB的MIMO-OFDMA系统的设计与仿真

摘 要

在信息时代的快速发展形势下，产生了越来越多的业务需求，用户对通信系统的性能提出了更高的要求。基于正交频分复用( Orthogonal Frequency Division Multiplexing，OFDM )技术和多输入多输出（ Multiple Input Multiple Output，MIMO ）技术的无线通信系统在增加系统容量、提高频谱利用率以及对抗频率选择性衰落等方面具备优越的性能，是未来通信领域中的关键技术。

本文首先阐述了MIMO技术和OFDM技术的国内外研究概况，然后通过分析MIMO技术和OFDM技术的基本原理和系统结构，设计出简单的MIMO-OFDM系统。基于MATLAB软件对所建立的MIMO系统的信道容量进行了仿真，并对SISO-OFDM系统和MIMO-OFDM系统的性能进行了比较，仿真结果表明，本文所提出的MIMO-OFDM系统方案能够在不增加误比特率的情况下增加信道容量，最后结合空时分组码（Space Time Block Coding,STBC）对MIMO-OFDM系统进行了完善并采用MATLAB对其性能进行了仿真，结果显示，相较于未完善的系统完善后的系统的误比特率指标明显降低，传输可靠性得到了极大的提高。

关键词：无线通信；MIMO；OFDM；误比特率

Performance Evaluation of MIMO-OFDMA

System using Matlab

Abstract

As the rapid development of information technology has resulted in more influences on people’s daily lives and businesses. Higher requirements should be provided by communication system to meet people’s needs. The communication system which based on the technology of Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) enables to not only increase the system capacity, but improve the spectrum utilization, and moreover to effectively against frequency selective fading, has become the key technologies in the field of communication in the future.

This paper first gives an in-detailed survey on MIMO and OFDM technologies in academic society. After that, we designed a simple MIMO-OFDM system by means of the analysis of the basic concepts and the architecture of MIMO and OFDM technology. Followed by performance evaluation via Matlab to compare SISO-OFDM and MIMO-OFDM systems in term of channel capacity and Bit Error Rate (BER) to validate the proposed MIMO-OFDM system outperforms SISO-OFDM. Finally, we further integrated space-time block codes into the proposed MIMO-OFDM system, through simulation results, we can observe that BER can be significant reduced compared to its counterpart which without implements space-time block codes. Keywords: Wireless communication，MIMO, OFDM, Bit Error Rate (BER)

目 录

第1章 绪论 ................................................................. 1

1.1课题背景 ............................................................. 1 1.2 国内外研究概况 ....................................................... 1

1.2.1 OFDM研究概况 ................................................ 1 1.2.1 MIMO研究概况 ................................................ 2 1.2.2 MIMO-OFDM研究概况 .......................................... 3 1.3 论文结构 ............................................................. 3 第2章 相关理论基础 ......................................................... 4

2.1 OFDM基本原理 ...................................................... 4

2.1.1 OFDM数学描述 ................................................ 4 2.1.2 OFDM系统框图 .................................................... 7 2.2 MIMO原理及数学描述 ................................................ 9

2.2.1 MIMO系统模型 ................................................ 9 2.2.2 MIMO信道容量 ............................................... 11 2.2.3 空时编码技术 .................................................. 11 2.3 无线信道环境及数学描述 .............................................. 12 第3章 仿真与分析 ........................................................... 14

3.1 MIMO信道容量仿真 ................................................. 14 3.2 MIMO-OFDM系统与仿真 ............................................. 16 3.3 基于STBC的MIMO-OFDM系统与仿真 ................................ 19 3.3 本章小结 ............................................................ 20 第4章 总结 ................................................................. 21

4.1 完成的工作 .......................................................... 21 4.2 不足与展望 .......................................................... 21 致 谢 ..................................................................... 22 参考文献.................................................................... 23 附录 ....................................................................... 24