基于USRP的认知通信系统的设计与实现-电子与通信工程专业论文.docx

摘要 随着无线通信技术的大量应用，可分配的频谱资源越来越少。频谱资源的匮 乏限制着无线通信发展，因此该问题受到人们广大关注。 导致频谱资源短缺的主要原因在于固定分配频谱政策。该政策造成了有限的 频谱没有得到很好地利用。认知无线电技术动态地在授权频谱中寻找频谱空洞， 并在不影响授权系统的情况下进行伺机利用。这种方法能够有效缓解频谱资源紧 张。本文主要通过研究认知无线电的关键技术从而实现对认知无线通信系统设计 研究，将认知无线电的关键技术投入到该系统中，根据环境的改变及时地通过感 知信息调整通信参数最终提高频谱资源利用率。 本文首先介绍了现有的认知无线电技术的基本概念和关键技术。其次基于软 件无线电平台设计了不同场景下的认知无线电演示系统方案，并在 linux 系统下 利用 USRP 和 GNU Radio 加以实现。最后对含有静默期的认知通信系统进行研究 通过改变静默期的时间实现吞吐量达到最大。 关键词：认知无线电 USRP GNU Radio 频谱管理 Abstract With the large number of applications of wireless communication technology, spectrum resources can be allocated less and less. Scarce spectrum resources limit the development of wireless communication , so the majority of people are concerned about this issue received .The main reason of the shortage of spectrum resources is fixed spectrum allocation policy . The policy caused a limited spectrum which has not been well utilized. Cognitive radio technology in the licensed spectrum dynamically find spectrum holes , and and in the case of without affecting the authorization system to use. . This method can effectively alleviate the spectrum resource constraints . This paper studies and implements three cognitive wireless communication systems on a software radio platform. Its purpose is to design three cognitive wireless communication systems without spectrum license, which can work independently. Through the accurate detection and effective spectrum management, efficient use of spectrum resources can be achieved. This paper first introduces the basic concept of cognitive radio technology existing and key technology. Secondly, based on software radio platform under different scenarios are designed cognitive radio demo system solutions, and under the Linux system using the usrp and GNU Radio to achieve them. Finally, contains the quiet period of cognitive communication system is studied by changing the quiet period of time to achieve maximum throughput. Keywords: cognitive radio USR P GNU Radio spectrum manage ment 目录 第一章 绪论 ..........