【作者】 陈卓；

【导师】 王玉良；

【作者基本信息】 北京邮电大学 ， 信号与信息处理， 2008， 硕士

【摘要】 宽带无线接入技术成为近年来通信技术市场的最大亮点,是构成未来通信技术的重要组成部分,在其中的移动宽带无线领域,IEEE802.16e具有技术上的权威性和先进性,因而对其物理层研究具有重要的现实意义。本文主要针对IEEE 802.16e的OFDMA物理层进行研究。首先,阐述了IEEE 802.16标准体系,802.16与WIMAX组织的关系以及802.16标准的相关演进过程,并概括介绍了IEEE 802.16e的协议结构以及OFDMA物理层。其次,在OFDM和OFDMA技术原理的基础上详细讨论了OFDMA物理层规范,包括符号描述,帧结构说明以及子载波分配。其中,在符号描述中,给出了时域描述、频域描述、原始参数、派生参数以及发射信号的数学表示。在子载波分配中阐述了下行FUSC、下行PUSC以及上行PUSC。然后,给出了OFDMA物理层仿真平台从发送端到接收端的系统结构、主要模块的设计原理以及软件设计接口说明。着重对信道编码方案—卷积码(CC)、分组Turbo码(BTC)、卷积Turbo码(CTC)以及低密度奇偶校验码(LDPC)进行了研究,得到了不同调制方式下各编码方式的系统仿真性能以及CTC、LDPC的不同译码迭代次数的系统仿真性能,同时也对各编码方式的性能优劣进行了对比。接着,对IEEE 802.16e中空时编码技术的应用进行了研究,给出了将Alamouti以及V-BLAST应用于OFDMA物理层系统的解决方案以及仿真平台软件设计的改进,仿真得到了应用空时编码技术后的OFDMA物理层系统性能。最后,对系统同步性能进行评估,通过理论分析与系统仿真,给出了频率同步误差和符号定时同步误差对系统性能的影响。更多还原

【Abstract】 Broadband Wireless Access technologies have recently received vast attentions in communication technology market, and become significant components in next generation communication technologies. In the area of mobile wireless broadband, IEEE 802.16e standard family serves as the official standard. It appears worthwhile to study the physical layers.This paper focuses on the OFDMA physical layers of IEEE 802.16e.Firstly, the IEEE 802.16 standards, the relationship between WIMAX and 802.16 standards and the evolution process of 802.16 are introduced. The structure and the OFDMA physical layer of 802.16e are also generally presented.Secondly, based on OFDM and OFDMA principles, the scheme of OFDMA physical layer is discussed in detail, including symbol description, frame structure and subcarriers allocation. In symbol description, time domain description, frequency domain description, primitive parameters, derived parameters and transmitted signal are given. In subcarriers allocation, downlink FUSC, downlink PUSC and uplink PUSC are described.Thirdly, system structure from transmitter to receiver of OFDMA physical layer simulation platform, the design principle of the main module and interfaces of software designing are described which focus on channel coding - CC, BTC, LDPC, CTC, and the system performance under different modulation, different coding and CTC, LDPC decoding with different number of iterations. At the same time, the performances of these channel coding are compared.Fourthly, space-time coding technology application in IEEE 802.16e is studied. The scheme of Alamouti and V-BLAST application and the improvement on software simulation platform interface design using STC are given. Also the results of system performances are listed.Lastly, the system performances of synchronization are evaluated. Through theoretical analysis and the actual system simulation, the effects of timing and frequency synchronization errors on the performance are given.更多还原