基于matlab的扩频通信系统仿真研究_学士学位论文.doc

沈阳理工大学学士学位论文 PAGE IV 基于matlab的扩频通信系统仿真研究 摘 要 自从扩频通信的概念在50年代开始成熟以后，此后的二十多年扩频通信技术仍得到很大的发展，但都只是局部的发展，如硬件的改进和应用领域的拓展。一直到80年代初期，扩频通信的概念都只是在军事通信系统中得到应用，这种状况到了80年代中期才得到改变。扩频技术发展到现在，CDMA技术成为目前扩频技术中研究最多的对象，其中民用通信的直接序列扩频技术广为应用。 本文阐述了扩展频谱通信技术的基本原理、主要性能指标及其工作特点，然后根据香农定理和柯捷尔尼科夫潜在抗干扰理论，通过MATLAB 提供的Simulink 仿真平台对直扩通信系统进行了仿真，建立了扩频通信系统仿真模型，详细讲述了各个模块的设计，并指出了仿真建模中要注意的问题。在给定的仿真条件下，运行了仿真程序，得到了预期的仿真结果。 关键词：扩频通信；信噪比；MATLAB Abstract Since the concept of spread spectrum communication became mature in the 50 s, After twenty years of spread spectrum communication technology still get great development. But only developed locally, such as hardware improvement and development in the field of application. Until the early 80 s, The concept of spread spectrum communication was only applied in the military communication system. The situation was changed until in the mid of 80s.Now, CDMA technology is the most studied objects in the spread spectrum technology, One of civil communication widely used direct sequence spread spectrum technology. This article elaborated the spread spectrum communication technologys basic principle, the main performance index and the operating feature, then it act according to the Shannon theorem and tan oak Jieer the Nikefu latent antijamming theory, provides visualization tool Simulink and Monte using MATLAB the Carb simulation algorithm, has established the wide frequency communications system simulation model, narrated in detail each modules design, and had pointed out in the simulation modelling must pay attention question. In assigns under the simulation condition, it moved the simulated program, obtained the anticipated simulation result. Key words: Spread Spectrum Communication; Signal-to-Noise; MATLAB 目 录 TOC \o 1-3 \h \z \u 1 绪论 h 1 1.1 课题背景 h 1 1.2 扩频通信的研究意义及现状 h 1 1.3 本课题研究的主要内容 h 2 2 扩频通信相关理论 h 4 2.1 扩频通信的相关原理 h 4 2.1.1 扩频通信的理论基础 h 4 2.1.2 扩频通信主要性能指标 h 5 2.1.3 数字调制技术 h 6 2.1.4 扩频通信的工作原理 h 7 2.1.5 扩频通信实现方法 h 7