【作者】 李婵娟；

【导师】 齐国清； 梁德群；

【作者基本信息】 大连海事大学 ， 信号与信息处理， 2007， 硕士

【摘要】 数字通信技术正在迅速发展，多种通信方式相继出现，但是作为其基础环节的调制技术却未见到大的改变。早期的脉冲幅度调制(PAM)、频移键控(FSK)、移相键控(PSK)仍在使用。90年代后期开始用于DSL的离散多音频(DMT)和当前用于3G的CDMA所基于的多载波原理早在1958年就已经确立。梁德群教授提出了非正交多重调制技术(NMT)，突破了正交性限制，带来了更高的频带利用率，有可能对数字通信的发展产生巨大影响。 在过去的几十年，宽带数字通信技术在骨干网和各种通信方式方面得到迅猛的发展；相比之下，用户接入网发展则要缓慢得多，成为整个通信网的“瓶颈”，特别是高速国际互联网的“瓶颈”。1990中后期开始，数字用户线(DSL)技术，成为解决这“最后一公里”接入瓶颈的主要技术之一。但是，现有的xDSL存在传输距离和速率的局限性。NMT可能克服这一局限性。 为了推进NMT的实用化，需要进行仿真研究，以验证NMT的技术可行性。尽管已经有两届研究生做过一些仿真研究，但是随着对工程要求的进一步了解发现欲将NMT用于实际还需要克服一些技术障碍，并进行更接近工程化的仿真。本论文的目的是实现NMT在ADSL信道上的仿真。 本文主要分析了非正交多重调制技术应用在ADSL工程线路上的一些性能指标，例如峰值均值比，并与传统的离散音频调制在同样的仿真条件下进行传送率的对比，同时利用MATLAB的SIMULINK仿真工具箱对该系统进行了模块化仿真。文中具体的编码技术在基本的NMT的构造基础上，采用了增加附加波的方法，解决了原始NMT编码在线路上的传输失真问题，有效提高了传送率。更多还原

【Abstract】 The digital communication technology is developing rapidly, and many means of communication appear one after another. However, the modulation technique has not actually changed significantly. The traditional modulation techniques such as PAM, FSK and PSK are still in use. The Discrete Multi-tone Modulation Technology (DMT) which started to be used in DSL in 1990s and CDMA which is used in 3G are based on multiple carrier waves principal. And it has been founded since 1958. Professor Dequn Liang brought forward the Non-Orthogonal Multi-Modulation Technology, which breaks through the limitation of orthogonal character, brings higher spectrum usage efficiency, and may have significant influence to digital communication.In the past few years, wide band digital communication technique in backbone and many means of communication were developing rapidly; In comparison, user access network developed much more slowly and became the bottleneck of the entire communications network, especially the high speed Internet. Since the middle of 1990s, DSL has been one of the ways to solve the problem of the last kilometer. But there are limitations in distance and bit rate of xDSL. NMT can overcome this limitation.In order to promote NMT to practical application, the simulation research is necessary to validate the feasibility of NMT. Although many researches have been done by some graduate students before, with further studies of the project request, many technical barriers must be overcome and the simulation should be done according to project requirement. The aim is to do simulation of NMT on ADSL loop.The dissertation analyses the performance of NMT on ADSL loop, for instance, PAR, and makes the comparison between NMT and DMT of transmission rate under the same condition. The dissertation also simulates the system with the toolbox SIMULINK in MATLAB. The specific coding technology which is based on NMT is adding the additional wave, which solved the problem of distortion in loop and effectively enhances the transfer rate.更多还原