摘 要
接收机是通信系统中的一个关键模块。在无线通信中，无线信道中的噪声，干扰及其时变特性，多径效应是直接作用于接收端的，所以接收机性能的优劣决定了整个系统的通信质量。最佳接收机的作用就是如何最佳地从噪声中提取有用信号。本文中主要介绍了匹配接收机，相关接收机和Rake接收机三种接收机或主要模块的FPGA设计。
FPGA技术的快速发展，很大地改变了传统数字系统设计的方法。FPGA以其开发周期短，保密性好等特点为人们对通信系统的研究提供了方便。FPGA是一种可编程逻辑器件，有其相应的编程语言，Verilog即是FPGA的编程语言，这种语言的特点是与C语言类似，过程化编程给设计者以很大的方便。
本文旨在对接收机原理充分了解的基础上对三种最佳接收机实现FPGA的设计，并在集成开发工具Quartus 2中进行设计和仿真。从原理入手，首先本文对三种接收机的原理逐一分析，介绍接收机所涉及的有关知识。然后在原理的基础上抽象出模型，算法和参数，据此实现最佳接收机的FPGA设计。
关键词：最佳接收机；FPGA；Verilog
中国石油大学（华东）本科毕业设计（论文）
ABSTRACT
Receiver is a key module of communication systerm. In wireless communication,the noise of wireless channel,time-varying characteristics and multi-path directly effect on the receiving end. Therefore,the merist of the receiver determines the quality of the entire system of communication. The role of the best receivers is how to extract the useful signal from the noise.In this paper,we mainly introduce the match receiver,the corre receiver and the key module of the Rake receiver.
The rapid development of FPGA technology,has greatly changed the traditional method of digital system design.Because the character of short cycle and good confidentiality ,FPGA is very fit for the communication system research. FPGA is a programmable logic device and Verilog is the programming language of FPGA.This language is similar with C language,so it’s easy for designer.
The purpose of this paper is to design FPGA of three best receiver,based on the fully understanding of the principle.And to design and simulation in the integrated development tools—quartus.Starting from the principle,firstly we analysize the principle of each of the three receiver and introduce the knowledge involved.Then we summing up the abstract model,algorithm and parameters.Accordingly to this,wo design FPGA of the best receiver.
KEY WORDS: best receiver;FPGA;verilog
中国石油大学（华东）本科毕业设计（论文）
目录
第一章 前 言 ··········································································· 4 1. 课题研究目的和意义 ····························································· 4 2. 课题研究现状 ······································································ 5 3. 本文组织结构 ············································· 错误！未定义书签。 4. 本章小结 ··················································· 错误！未定义书签。 第二章 关键技术··············································· 错误！未定义书签。 1. 爬行器相关技术 ··································································· 7 1.1 Web爬行器 ············································· 错误！未定义书签。 1.2 基于主题的Web爬行器 ····························· 错误！未定义书签。 1.3 网页搜索策略 ········································· 错误！未定义书签。 1.4 HTTP服务器与HTTP客户机之间的会话 ········· 错误！未定义书签。 1.5 HTML页面结构 ········································ 错误！未定义书签。 1.6 站内链接与站外链接 ································ 错误！未定义书签。 1.7 Java的多线程机制 ·································· 错误！未定义书签。 2. 分类器相关技术 ·································································· 10 2.1 文本自动分类技术 ··································· 错误！未定义书签。 2.2 向量空间模型 ········································· 错误！未定义书签。 2.3 kNN分类算法 ·········································· 错误！未定义书签。 3. 本章小结 ··········································································· 11 第三章 系统需求······································································· 13 1. 用户需求 ··········································································· 14 1.1 用户界面 ··············································· 错误！未定义书签。 1.2 用户操作 ··············································· 错误！未定义书签。 2. 设计目标 ··········································································· 15
中国石油大学（华东）本科毕业设计（论文）
3. 实现工具及运行环境 ···························································· 19 3.1 开发工具 ··············································· 错误！未定义书签。 3.2 软件运行环境 ········································· 错误！未定义书签。 4. 本章小结 ··················································· 错误！未定义书签。 第四章 概要设计······································································· 19 1. 总体设计 ··················································· 错误！未定义书签。 1.1 系统体系结构 ································································· 20 1.2 基本设计概念 ········································· 错误！未定义书签。 1.3 处理流程 ··············································· 错误！未定义书签。 2. 模块设计 ··················································· 错误！未定义书签。 2.1 程序模块划分和功能分配 ·················································· 25 2.1.1 程序模块清单···································· 错误！未定义书签。 2.1.2 各程序模块功能描述 ·························· 错误！未定义书签。 2.2 功能-模块对照表 ····································· 错误！未定义书签。 3. 软件模块逻辑关系 ······································· 错误！未定义书签。 4. 本章小结 ··················································· 错误！未定义书签。 第五章 详细设计······································································· 30 1. 模块详细设计 ····································································· 33 1.1 URL存储器模块 ······························································· 33 1.2 协议模块 ··············································· 错误！未定义书签。 1.2.1 HTTP协议模块 ··································· 错误！未定义书签。 1.2.2 机器人禁止访问协议模块 ············································ 36 1.3 处理模块 ······································································· 38 1.3.1 网页文件分析模块 ····················································· 38 1.3.2 网页信息保存模块 ····················································· 40 1.3.3 训练集特征向量读取 ·················································· 41
中国石油大学（华东）本科毕业设计（论文）
1.3.4 待分类网页特征向量读取 ············································ 43 1.3.5 网页分类模块···························································· 44 1.3.6 网页存储模块···························································· 47 1.4 站内（外）链接模块 ························································ 48 1.5 日志管理模块 ································································· 49 1.6 线程控制器 ···································································· 51 1.7 结果生成模块 ································································· 53 1.8 计时模块 ······································································· 54 1.9 界面设计 ······································································· 55 2. 系统类说明 ········································································ 57 3. 本章小结 ··········································································· 57 第六章 系统测试及运行结果分析 ················································· 58 1. 运行环境 ··········································································· 58 2. 运行测试 ··········································································· 58 2.1 软件运行 ······································································· 58 2.2 运行界面 ······································································· 58 3. 运行结果分析 ····································································· 63 4. 软件特色 ··········································································· 67 5. 本章小结 ··········································································· 69 第7章 结 论 ·········································································· 70 1. 毕业设计完成的任务 ···························································· 70 2. 系统存在的不足和有待改进的地方 ·········································· 70 3. 收获和总结 ········································································ 72 致 谢 ······························································ 错误！未定义书签。 参考文献 ··················································································· 75 附 录 ······················································································ 77
最佳接收机的FPGA设计与实现
