摘 要随着移动通信的普及，无线通信遇到了新的瓶颈，像传输速率、通信覆盖面积、成本等的高要求都极大地抑制了无线通信的进一步发展。而无线中继技术扩大了基站的覆盖范围，能够有效提高无线网络容量，协助信源节点传输，能够提高传输系统的可靠性。研究表明，与直接联通的链路相比，使用中继协议会得到更大的分集增益和中断增益。协作分集的提出进一步促进了无线中继技术的发展，不同的协作中继传输方式被提出以期获得更高的传输速率、更好的中断性能等。换言之，传输速率、中断概率等可以作为无线中继传输方案的设计标准。86069

本文比较系统的阐述了无线中继传输提出的背景、发展、原理以及系统模型，并对协作中继传输进行了介绍和描述，了解了动态放大转发协议、量化-转发协议、动态解码转发协议、带时间分配策略的解码转发协议以及带时间分配策略的动态解码转发协议的分集复用折中性能，并着重认识了带时间分配策略的动态解码转发中继传输方式。本文对带有时间分配策略的动态解码转发中继协议和传统的动态解码转发中继协议的中断概率进行仿真，比较了不同中继传输方案的中断性能。实验结果表明，带有时间分配策略的动态解码转发协议的中断性能要明显优于其他中继传输方式。

毕业论文关键词：无线中继；协议；分集复用折中；中断概率

Abstract With the popularity of mobile communication,wireless communication has encountered new problems。Such as transmission rate,communication coverage area, cost and other high requirements have greatly inhibited the further development of wireless communications。Wireless relay technology has been widely concerned by the academia in recent years in that it can expand the communication coverage,improve the capacity of the edge users and reduce the transmission energy consumption。Efficient relay transmission technology  can not only significantly reduce the power consumption and the complexity of the signal processing,but also bring performance improvement。And accurate theoretical performance analysis is an important means to guide the design of wireless communication systems and performance optimization。By optimizing the theoretical analysis, such as minimizing outage probability, maximizing the average rate, etc, some optimal system parameters can be obtained。They provide theoretical guidance for the transmission system design。It has shown that compared with direct communication link,relay protocol would help to achieve a higher persity gain and interrupt gain。

This paper systematically describes the background, development, principle and system model of wireless relay transmission,and cooperative relay transmission is introduced and described。In terms of the persity multiplexing tradeoff performance,the dynamic amplify-and-forward protocol,quantize-and-forward protocol,dynamic decode-and-forward protocol and decode-and-forward with time allocation and dynamic decode-and-forward with time allocation is understanded,and the paper focuses on understanding the dynamic decode-and-forward with time allocation protocol。The outage probability of the dynamic decode-and-forward relay protocol with time allocation strategy and the traditional dynamic decode-and-forward relay protocol is simulated。Outage performance of different relay transmission schemes is compared。The experimental results show that the outage performance of the dynamic decode-and-forward protocol with time allocation strategy is obviously better than that of other relay transmission protocols。

Keywords:wireless relay; protocol;persity multiplexing tradeoff ; outage probability

目 录

第一章 绪论