摘要:社会的发展和信息化脚步的推进使人们对移动通信服务的期望值日渐提高,传统的无线语音服务已经不能够满足人们对移动通信的需求,无线网络提供的多媒体服务才是人们未来的主流需求。当前已在全球多数国家使用的第三代移动通信技术,由于该技术自身的传输速率的限制,已经无法满足人们的实际需求。因此,OFDM技术作为下一代移动通信技术的代表,目前受到了越来越多人的关注,正发展为4G移动通信的主流技术。
本论文首先概括性地介绍了正交频分复用OFDM技术的发展史和我们对OFDM技术研究的意义和必要性,然后重点介绍OFDM技术的工作原理和模型,以及OFDM技术的一些特点如抗多径衰落,循环前缀技术等。最后给出OFDM系统的SIMULINK仿真模型,采用可视化工具GUI完成该系统界面的设计,在仿真的结果下分析OFDM系统的性能。
关键字 OFDM;Simulink仿真;GUI
Abstract:Promotion of social development and the pace of information technology enable people to raise the expectations of mobile communications services. Traditional wireless voice services has not been able to meet the demand for mobile communications, and multimedia services offered by wireless networks is the mainstream of the future needs of the people. Currently the third generation mobile communication technology is used in most countries around the world. This technology is unable to meet the actual needs of people, due to the limitations of the technology transfer rate. Therefore, OFDM technology,as a representative of the next generation of mobile communication technology, is currently subject to the attention of more and more people, and it is developing into a mainstream technology for 4G mobile communications.
The paper begins with an overview of the history of OFDM (Orthogonal Frequency Division Multiplexing) technology’s development and the significance and necessity of OFDM technology, then,focuses on introducing the working principle of the OFDM technology and models, as well as some of the features of the OFDM technology such as anti-multipath fading, cyclic prefix technology. Finally OFDM system SIMULINK simulation model is given and then using visualization tools GUI interface to complete the system. Then the paper analyzes the performance of OFDM systems on the results.
Keywords OFDM Simulink-simulation GUI
OFDM技术由于其本身的强大功能,被公认为是移动通信领域中相当有潜力的技术之一,它具有很多其它无线传输技术未有的优点:良好的抗衰落能力,较高的带宽利用率,很好的抗码间干扰能力等,适合于高速无线数据传输系统,具有很好的研发和应用前景。目前,OFDM技术被广泛应用于无线局域网、HDTV、DAB、DVB等系统中,并可能成为第四代移动通信系统的核心技术。但OFDM也存在着一些缺点需要克服,如何更好的实现同步技术是OFDM的研究热点之一,对OFDM来说具有举足轻重的影响。寻找一种易于实现、性能良好的同步方案是一个仍旧需要继续研究的课题。本文概括性地分析了OFDM的同步技术,并对几种主要的同步技术实现方法进行了简要介绍。