双路信号发生器的设计

双路信号发生器的设计摘要直接数字频率合成[1]((Direct Digital Synthesizer,DDS)是七十年代初提出的一种新的频率合成技术。

因为其数字结构满足了现代电子系统设计的许多要求，因此得到广泛的应用。

随着复杂可编程逻辑器件（CPLD）的出现，一种全新现代电子数字系统的设计方法被提出。

本论文结合这两项技术，并利用单片机控制模块实现人机交流，设计了一种低成本双路正弦波发生器。

在实现的过程中，通过利用ALTERA公司的EPM570GT100作为产生波形数据的主芯片，充分体现了芯片的超大系统集成性、快速合成和可编程性。

利用了MSP430F149低功耗，让总系统实现较低功耗。

CPLD芯片的设计和与MSP430的接口设计是其中的难点，本文通过串行通信实现单片机和CPLD的通信。

利用ALTERA公司的QUARTUS这个软件并结合硬件描述语言verilog-hdl来实现。

本文首先介绍了信号发生器的研究背景及意义和国内外的发展现状。

进行DDS原理及相关理论的分析。

接下来对主要的硬件电路进行设计，最后利用EPM570GT100实现DDS的设计，根据设计原理的功能进行划分，将整个系统分为控制模块（MSP430）、CPLD模块（DDS软件实现）和模拟电路设计。

实现了双路信号发生器设计。

关键词：直接数字频率合成；复杂可编程逻辑器件；信号发生器Dual signal generator designAbstractDirect digital frequency synthesis (DDS) is presented in early 1970s .DDS as a kind of new frequency synthesis technology and is widely used because of its digital structure,which meets many requirements of modern electronic system design.With the emergence of complex programmable logic device (CPLD), a new design method of modern digital electronic system bining these two technologies and using model of single-chip microcomputer control ,human-computer interaction is realize in this paper and a low d ouble channels sine wave generator is designed.EPM570GT100 of ALTERA corporation as the main chip is chosen to generate waveform data in the process owning to its large scale,high speed and programmability.Taking advantage of its low power of MSP430F149 makes power consumption of the system lower.In the design,how to design CPLD and the interface between the CPLD and the control chip,which is implemented by serial communication, is the difficulty.the design used the software Quartus II and hardware description language Verilog-HDL solves it successfully．In this paper,the research background and significance of signal generator and the domestic and foreign development present situation is introduces firstly. The principle of DDS and the related theoretical analysis are introduced.then the key hardware circuit is achieve. Finally,EPM570GT100 of ALTERA corporation implement Direct digital frequency synthesis.According to the function,the system can be divided into control module (MSP430),the CPLD module and analog circuit design.A two channel signal generator is achieve.Key words: DDS; Complex Programmable Logic Device; Signal Generator目录摘要 (I)Abstract .................................................................................................................. I I第1章绪论 (V)1.1 课题研究背景及意义 (V)1.2 国内外波形发生器的发展现状 (VI)1.2.1 波形发生器的发展状况 (VI)1.2.2 国内外波形发生器产品比较..................................................... V II1.3 主要内容：.......................................................................................... V III 第2章双路信号发生器方案和理论介绍.. (IX)2.1方案的选择与确定 (IX)2.1.2单片机选择 (IX)2.1.3 DDS模块方案选择 (IX)2.2系统总分析 (X)2.3 DDS相关理论分析 (X)2.3.1 DDS算法分析 (X)2.3.2 DDS原理..................................................................................... X II2.3.3 DDS特点.................................................................................... X III2.4调幅分析................................................................................................ X V2.6 正弦波产生原理分析 (XVII)2.7差频分析 (XIX)2.7.1差频方案选择 (XIX)2.7.2 差频理论分析 (XIX)2.8调相分析(QUS为CPLD产生的频率可调方波) ................................ X X 第3章关键电路设计实现.. (XXI)3.1 MSP430F149电路设计 (XXI)3.1.1 MSP430时钟 (XXII)3.1.2 MSP430F149各种端口 (XXII)3.1.3 MSP430系列的通用串行通信模块 (XXII)3.1.4 MSP430最小系统电路设计.................................................... X XX3.2 CPLD外接电路 (XXXII)3.3 低通滤波器的有关理论................................................................ X XXIII3.3.1滤波器的分类....................................................................... X XXIV3.3.2模拟滤波器的传递函数....................................................... X XXIV3.3.3模拟滤波器的频率特性........................................................ X XXV3.3.4滤波器的主要特性指标........................................................ X XXV3.3模拟电路设计 (XXXVII)3.3.2调幅模块 (XXXVII)3.3.3正弦信号的产生................................................................... X XXIX3.3.4 差频模块.................................................................................... X LI 第4章软件实现........................................................................................... XLIII4.1 MSP430程序设计............................................................................. XLIII4.2 CPLD程序的设计.......................................................................... XLIII4.2.1接口模块.................................................................................. X LIV4.2.2 10KHZ方波产生模块.............................................................. XLV4.2.3 DDS模块.................................................................................. XLV4.2.4可调占空比方波的产生......................................................... X LVII 结论.............................................................................................................. XLVIII 参考文献......................................................................................................... X LIX 附录A .................................................................................................................... L 附录B ................................................................................................................ L VI 致谢................................................................................................................. L XXI第1章绪论1.1 课题研究背景及意义信号发生器简称信号源，是指产生所需参数的电测试信号的仪器，主要应用在电子电路、信号通信等领域的实验与检测中。