摘要 随着FPGA近年飞速的发展，数字通信技术与FPGA的结合成为了现代通信系统发展的一个趋势。数字调制在数字通信技术中举足轻重。现代通信中，键控法是一种十分常用的数字调制方法，多进制键控系统有三种基本方法，即多进制数字振幅调制（MASK)，多进制数字频率调制（MFSK）以及多进制数字相位调制（MPSK）。多进制键控系统可以看作二进制键控系统的推广，与二进制键控系统相比，其可以提高信息速率（传信率），使系统频带利用率增大；还可以降低码元速率，提高传输的可靠性，可以更好的满足未来通信的需要。本文先对三种多进制调制方法做了研究，然后在QuartusⅡ平台上运用VHDL语言对以上三种调制方法进行设计，编译后再进行仿真，观察仿真波形后证明程序可行。最后根据波形分析得出结论：多进制数字信号调制较之二进制数字信号调制确实具有其优越性，但是也有更难应用至现实生活等缺点。26991
关键词  FPGA 数字调制 多进制 VHDL QuartusⅡ
毕业论文设计说明书外文摘要
Title：Modeling and design of multi-band digital modulation system                  
Abstract
With the rapid development of FPGA recent years, digital communications technology and FPGA combination has become a trend in the development of modern communication systems. Digital modulation plays a important role in digital communication technologies.In modern communications, keying method is a very common digital modulation method,M-ary keying systems as binary digital modulation promotion, there are three basic methods, namely multi-band digital amplitude modulation (MASK), multi-band digital frequency modulation (MFSK) and multi-band digital phase modulation (MPSK).M-ary keying systems can be seen as the promotion of binary keying system,compared  with the binary key system, it can improve the information  rate (signaling rate)to make the system bandwidth efficiency increase;it can also reduce the symbol rate, improve the reliability of the transmission, so we can better meet the needs of future communications.Therefore, this article first studies three-ary modulation methods , and then use VHDL languages on QuartusⅡ platform to design three modulation methods above,compiles and then the simulates, the simulation waveform observation proves program is feasible. Finally, based on the waveform analysis concluded: Multi-band digital signal modulation than binary digital signal modulation does have its advantages, but there are more difficult to apply to real life and other shortcomings.
Keywords FPGA Digital modulation Multi-band VHDL QuartusⅡ
目   次
1  引言 1
1.1 课题研究背景 1
1.2数字调制的原因与意义 2
1.3二进制数字调制的基本方法 2
1.4课题的内容与意义 5
  2  FPGA的介绍 7
2.1 FPGA的概念 7
2.2 FPGA的基本结构与特点 8
  3  VHDL语言的介绍 9
3.1 VHDL的定义 10
3.2 VHDL语言的特点10
3.3 VHDL语言的程序结构 10
3.4 实验平台的选择 11
4  多进制幅度调制（MASK） 12
4.1 多进制幅度调制的介绍 12
4.2 课题采用方法及程序 13
4.3 仿真波形图及分析 15
5  多进制频率调制（MFSK) 17
5.1 多进制频率调制的介绍 17
5.2 课题采用方法及程序 17
5.3 仿真波形图及分析 20
6  多进制相位调制（MPSK） 22
6.1 多进制相位调制的介绍 22
6.2 课题采用方法及程序 22
6.3 仿真波形图及分析 24
7  课题拓展 26
7.1 解调的介绍与意义 26
7.2 对MPSK解调研究 26
7.3 实际波形与分析 29
7.4 研究中的问题 29 VHDL多进制数字调制系统的建模与设计:http://www.751com.cn/tongxin/lunwen_21324.html