1、 基于基于 FPGA 的直接数字合成器设计的直接数字合成器设计 The design of direct digital frequency synthesizer based on FPGA I 摘摘 要要 直接数字合成(Direct Digital Synthesis)技术采用全数字的合成方法。本设计结 合了EDA技术和DDS技术，EDA技术是现代电子设计技术的核心，是以电子系统 设计为应用方向的电子产品自动化设计技术。DDS技术则是最为先进的频率合成 技术，所产生的信号具有频率分辨率高、频率切换速度快、频率切换时相位连续， 输出相位噪声低和可以产生任意波形等诸多优点。 本文在对现有DDS
2、技术的大量文献调研的基础上，提出了符合FPGA结构的 DDS设计方案，并利用Quartus II软件在Cyclone II系列器件上进行了实现，详细的 介绍了本次设计的具体实现过程和方法，将现场可编程逻辑器件FPGA和DDS技术 相结合， 体现了基于VHDL语言的灵活设计和修改方式是对传统频率合成实现方法 的一次重要改进。FPGA器件作为系统控制的核心，其灵活的现场可更改性，可再 配置能力，对系统的各种改进非常方便，在不更改硬件电路的基础上还可以进一 步提高系统的性能。文章给出的仿真结果，经过验证本设计能够达到其预期性能 指标。 关键词：关键词：直接数字合成器；现场可编程逻辑门阵列；硬件描述语
3、言 II ABSTRACT The DDS technique adopts full digital synthesis methods. The design combines EDA and DDS technology, EDA technology is the design of modern electronic technology at the core, electronic system design direction for the application of electronic design automation products technology. DDS
4、 technology is the most advanced frequency synthesizer technology. The generated signals have advantages of high frequency resolutions, fast frequency switching, continuous phase while frequency switching, low noise phase and being able to generate arbitrary waveforms. In this paper, after reviewing
5、 a lot of literatures published on DDS technology, DDS scheme based on FPGA structure are proposed, and then implemented in Cyclone II series FPGA using Quartus II tool.the paper introduced the concrete implementation process, this way associates DDS with field programmable gate array FPGA technolog
6、y , the way based on VHDL is flexible in designing and modifying, which is a important innovation to the tradition synthesize way, FPGA device control core as system, its flexible scene can altering, can dispose ability again, very convenient to various kinds of improvement of the system, can also improve systematic performance further on the basis of altering hardware circuit. at the end of paper , the author displays simulation result, after verification, the design meets the demand of o
