扩频通信中伪随机码设计.docVIP

扩频通信中的伪随机码设计 摘 要 扩频通信与常规通信系统相比，具有较强的抗人为干扰、窄带干扰和多径干扰能力，和信息隐藏以及多址必威体育官网网址通信等优点，因此在军事通信、移动通信等领域得到了广泛的应用。扩频通信的核心问题之一是扩频码的设计，即PN码的设计问题。随着扩频通信技术的发展，伪随机码在扩频通信中的作用越来越重要。本文主要介绍m序列、M序列、Gold序列及混沌序列的原理、构造方法及特性分析，并通过Matlab进行仿真来验证各个伪随机序列的随机特性，以期为以后的扩频通信中伪随机码的设计提供一些有意义的指导。 关键词：计算机仿真;扩频;m序列;M序列;Gold序列;混沌序列 The pseudo-random code design in Spread Spectrum Communications ABSTRACT Spread spectrum communication has many advantages over the conventional communication systems such as strong anti-human interference, narrow-band interference, multipath interference capabilities, information hiding, multiple access confidential communications and so on. So it has been widely applied in military communications, mobile communications and other fields. One of the core issues in Spread Spectrum Communications is the design of Spreading Codes. That is the designing problem of PN code. With the development of Spread spectrum communication technology, Pseudo-random code plays a more and more important role in Spread spectrum communication. This paper presents the principles, structures and character analyzing of m sequence, M Series, Gold sequence and chaotic sequence. Furthermore, random character of various pseudo-random sequences is verified by simulation experiments with Matlab in order to provide some meaningful guidance for Pseudo-random code design in Spread Spectrum Communications. Keywords: computer simulation ;Spread spectrum ;m-sequence;M-sequence; Gold- sequence;haotic-sequence 目 录 1. 绪论 1 1.1 研究的目的和意义 1 1.2 国内外研究现状 1 1.3 扩频的理论基础 2 1.3.1 香农信道公式 2 1.3.2 最佳相关接收 4 1.3.3 伪随机序列的相关概念 4 1.3.4 伪随机序列的数学定义 5 1.3.5 伪随机序列的相关性 6 1.3.6 有限域的理论简介 7 1.4 本文主要研究内容 10 2. 常用伪随机码 10 2.1 m序列 10 2.1.1 m序列的定义 10 2.1.2 m序列的性质 11 2.1.3 m序列的相关性 11 2.1.4 m序列的构造 12 2.1.5 m序列的simulink仿真 12 2.1.6 m序列的相关性仿真 14 2.2 M序列的性质 14 2.2.1 M序列的仿真 16 2.3 Gold序列 17 2.3.1 m序列优选对 18 2.3.2 Gold序列产生的方法 19 2.3.3 Gold序列的相关特性 20 2.3.4 Gold序列的相关特性仿真 21 2.3.5 Gold序列的相关特性与m序列的相关特性比较仿真 22 2.3.6 平衡Gold码 23 2.3.7 平衡码的产生 24 2.3.