基于ieee 802.11n的波束赋形技术分析based on the ieee 802.11 n beam informs technical analysis.docx

摘要
IEEE 标准新引入的多输入多输出(MIMO)空分复用技术极大地提升了物理层传输速率。基于 MIMO 的波束赋形技术通过对发送信号进行加权,能够进一步改善接收状况。
本文主要研究基于 IEEE 的波束赋形技术,并在传统点对点通信模式的基础上利用多用户波束赋形实现下行空分多址接入(SDMA),提高系统吞吐量。
本文首先介绍了无线局域网的基本组成结构,并对 中的媒体接入控制(MAC)层和物理层(PHY)分别进行了简要描述。其次详细介绍了常见的单用户与多用户波束赋形算法。最后通过引入块对角化(BD)隐式反馈波束赋形算法,并修改相应 MAC 层协议,提出了在 现有框架下实现下行 SDMA 的整体方案。
该方案完全兼容 标准,用户设备不做任何修改即可接入信道。仿真结果显示,该方案能够有效支持下行 SDMA 通信。
关键词: 波束赋形 块对角化 空分多址接入 无线局域网
Abstract
Physical layer (PHY) data rates in are significantly improved through the use of multiple-input multiple-output (MIMO) spatial multiplexing. By applying weights to the transmitted signal, beamforming based on MIMO can further improve reception.
The main work of this paper is to study beamforming techniques based on IEEE . In particular, multi-user beamforming algorithm is exploited to implement downlink spatial division multiple access (SDMA), which can work throughput on the basis of traditional point-to-point transmission mechanism.
At the beginning,ponents as well works types of wireless local
work (WLAN) are introduced, followed by brief descriptions of MAC and PHY matters in . Secondly, common beamforming techniques in both single-user and multi-user scenarios are analyzed in detail. Finally, taking advantage of the block-diagonalization (BD) implicit feedback beamforming algorithm, together with the help of modified MAC protocol, an overall scheme for downlink SDMA in the existing framework of is proposed.
The scheme maintains patibility with standard. In addition, stations are able to get access to channel without any modification. Simulation results show that the proposed scheme supports the SDMA effectively in the downlink transmission.
Keywords: Beamforming BD SDMA WLAN
目录
第一章绪论..................................................................................................................... 1
引言............................................................