无线收发机中的扩频解扩技术研究与实现
关键词 m序列 直序扩频系统 匹配滤波器 数腔振荡器
毕业设计说明书（论文）外文摘要
Title Research and Implementation of Spreading Spectrum and
Dispreading Techniques in the Wireless Transceiver.
Abstract
As the popularization of radio communication, the increasing need for co-operation and the lack of radio spectrum resource, traditional radio communication can not satisfy the need of development and facing innovation and breakthrough. How to use the spectrum effectively and how to adapt to all kinds of application environment becomes a hot topic. The software radio technology put forward a feasible way to solve it, its low cost and multi-function becomes a focus. It also changes the method of designing. Direct sequence spread spectrum is a key technology in the intending communication system. Spread spectrum communication has characteristics of anti-interference, anti-fading, and is therefore widely used in military carrier communications. In this paper, the composition and working principle of spread spectrum communication system is researched. It also analysis the generation mechanism， spectral characteristics of the m sequence，and the general principles of the sequence design. The technologies of digital demodulation, digital matched filter and numerical controlled oscillator, are employed．
Keywords m sequence DS-SS communication DMF NCO
目 录
1 绪论 1
1.1 扩频通信概述 1
1.2 当前国内外研究水平概述 1
2 扩展频谱通信技术 3
2.1 概念与基本原理 3
2.2 扩频系统的指标、特点、分类 5
2.3 直序扩频 8
3 频率合成技术 11
3.1 原理与应用 11
3.2 DDS设计 11
4 扩频序列设计 17
4.1 伪随机序列的概念与性质、伪随机序列的选取原则 18
4.2 m序列的性质与产生机理 19
4.3 m序列的实现 19
4.4 其它伪随机序列的介绍 25
5 调制 26
5.1 模块设计 26
5.2 调制方案的实现和对比 26
6 接收机设计与实现 29
6.1 同步 29
6.2 匹配滤波器DMF的设计和实现 32
6.3 二进制差分相移键控(2DPSK)解调 37
结论 39