1、大学学士学位论文 I 摘 要 对于移动通信系统，总要受到功率和带宽的限制，而且 CDMA 扩频通信系统又是一个干扰受限系统，在确保通信质量的前提下要求支持高速率、大容量，这些技术上相互制约甚至相互矛盾的要求，导致采用了极其复杂的调制方式和脉冲成形技术，以及差错控制和高级信号处理技术。 软扩频技术是近年来将直接序列扩频技术与编码技术相结合发展而来的一种新型基带扩频技术，也是近年来应用较多的一种扩频技术，主要应用于那些频带受限而数据率又要求较高的通信系统中，如突发通信、计算机无线通信和无线局域网通信等。在一定条件下，它具有和一般直序列 扩频系统相同的
2、抗音调干扰和抗宽带干扰能力。 目前，计算机仿真的基本内容包括系统、模型、算法、计算机程序设计与仿真结果显示、分析与验证等环节。本篇论文拟定研究的目的是利用 MATLAB 软件对现代通信系统的关键环节进行计算机仿真，重点是移动通信系统中常用的 CDMA 软扩频通信中伪随机码部分的仿真。 m序列是一种典型的伪随机序列，它在软扩频通信、流密码、信道编码等领域有着十分广泛的应用。本文介绍了 m序列构造方法及基本性能，并利用 Matlab 及 M 语言编程实现它们的产生和分析。 关键词 ：软 扩频通信； m序列； Matlab 仿真 大学学士学位论文 &n
3、bsp;II Abstract Normaly mobile telecommunication systems always be restrict by power and bandwidth,and CDMA system is a interference-limited system.As keep the communications quality the same time high speed data transmition service and large system capacity are needed. These request even maybe rest
4、rict in technology,so these request need more complex radio technology and error control technology,also has high level signal processing technology. In recent years,soft spread spectrum technology is anew type of baseband spread spectrum technology,which combining the direct sequence spread spectru
5、m technology and coding technology, and be used widely in many different sulations.It mainly applied data rate and communication systems,such as emergency communication, computer, wireless communication and wireless local area network communication, etc.Under certain conditions, it has general direc
6、t sequence spread spectrum system, and the same tone interference and broadband interference resistance ability. As the moment, the basic elements include computer simulation systems, models, algorithms, computer programming and simulation results show that analysis and verification aspects. The purpose of this paper is to use the development of MATLAB software, the key to modern communications systems by computer simulation, focusing on commonly used in mobile communication systems in CDMA soft spread spectrum PN code part of the sim
