摘要传统的频率调制（FSK）和相位调制（MSK）两种数字调制方式都存在频谱利用率低、抗多径衰落能力差、功率谱衰减慢、带外辐射严重等不足。相比较之下，正交振幅调制(QAM)是一种相位和振幅联合控制的数字调制技术,它不仅可以得到更高的频谱效率,而且可以在限定的频带内传输更高速率的数据。这在带宽资源日益枯竭的移动通信和卫星通信领域中显现出该调制技术的优越性，因而有着非常广泛的应用范围,其不仅在移动通信领域应用,还在有线电视传输、数字视频广播卫星通信(DVB-S)等领域也都得到广泛应用。64577

本文在对QAM调制的基本原理、MATLAB仿真和FPGA开发环境等进行深入研究的基础上,通过Matlab 2010b软件的编程实现了16QAM调制解调系统的建立并对其进行仿真分析。之后利用Quartus II 9.0sp2作为软件开发环境,设计并实现了16QAM调制系统的基带成形部分、载波信号产生部分、调制部分等关键模块。其中关于载波信号产生部分,本文采取DDS运用的正弦查表来实现DDS中相位幅度的转换,该方法简单且容易实现,且频率分辨率高、输出频点多、可达2的N次方个频点。

本文采用Verilog硬件描述语言对16QAM调制系统中的关键模块进行RTL级描述,完成了功能上的仿真验证,通过对比验证了设计的正确性,为下一步的硬件实现打下了很好的基础。

毕业论文关键词 16QAM 调制 MATLAB FPGA

毕业设计说明书（论文）外文摘要

Title  Analysis and implementation of MQAM modulator               Abstract

The traditiona digital modulations like frequency modulation (FSK) and phase modulation (MSK) have problems such as low utilization of the spectrum, poor anti-multipath fading ability ,the slow decay of power spectrum, serious  out-of-band radiation. In contrast, quadrature amplitude modulation (QAM) is a digital modulation technique with phase and amplitude control, it not only can get higher spectrum efficiency, but also  get higher data transmission rate in a limited frequency band. It shows the superiority in the mobile communication and satellite communication field with less bandwidth resource, which means has a very wide range of applications. not only in the field of mobile communication application, but also in cable television transmission, digital video broadcasting satellite communications (DVB-S) and other fields .

In this paper, based on the basic principle of QAM modulation in the MATLAB simulation and the FPGA development environment, I use Matlab 2010b software programming to achieve the system of 16QAM modulation and demodulation ,then I read its simulation analysis. Continuely I use Quartus II 9.0sp2 as the software development environmen to design some key modules of 16QAM modulation system. AT the carrier signal generating part, I adopted DDS using sin look-up table to realize the conversion of phase and amplitude in DDS, which is simple and easy to achieve, and has a high frequency resolution and up to 2N times  output frequency points.

This paper uses the Verilog language to describe the key module parts of 16QAM modulation system in RTL way. the simulation function is excellent,providng the correctness of the design, and making a good foundation for the next step in hardware implementation.

Keywords  16QAM  MATLAB  modulate   FPGA

1  绪论 1

1.1  课题的背景和意义 2

1.2  QAM发展及应用现状 3

1.3  本文的内容及结构 4

2  QAM调制技术原理 4

2.1  QAM技术的原理