摘 要文章开篇对现有的一些调制、解调技术原理进行了系统地概括与归纳,例如说AM、FM、2ASK、2PSK 等一些模拟或数字信号的产生与解调。在此基础上制造性的提出了基于 CPLD 的 16QAM 调制解调器的方案,同时简要阐述了各个模块的组成及其原理。至此,利用 MATLAB 对 16QAM 的性能进行了仿真,绘制了星座图、信号轨迹图、眼图以及误码率曲线,并对它们进行了简要的分析,16QAM 可以合理的安排各个矢量端点,使它们间的最小距离最大,从而使系统达到最佳的误码率。所以说,QAM调制解调技术能够实现在提高信息传输速率的同时降低误译码率,从而改善通信质量。关键词:调制解调;载波恢复;QAMABSTRACTAt first,article introduces the existing modulation demodulation principle, such as AM、FM、2ASK、2PSK signal generation and demodulation principle. we proposed the 16 qam modem based on CPLD, and expounds the composition and principle of each module. At this basis, Using MATLAB simulation to the performance of 16 QAM map of the constellation diagram, signal path, eye diagram and bit error rate curve, and carried on the brief analysis.16 qam can reasonable arrangement each endpoint vector, the minimum distance between them is the largest, which make the system achieve the best bit error rate.QAM modulation demodulation technology can be achieved in improving information transmission rate and reduce the decoding error rate.Keywords: modulator/demodulator;carrier recovery;QAM目 录第一章 绪论..........................................................................................................11.1 引言................................................................................................................11.2 论文讨论的主要内容....................................................................................1第二章 调制解调技术原理..............................................................................32.1 模拟调制技术...................................................................