基于单片机的快速扫频信号发生器设计.doc

基于单片机的快速扫频信号发生器设计
有电路图 程序

摘要：信号发生器又称信号源或振荡器，是一种非常重要的仪器，在通信、测控、医疗、教学领域、实践应用领域及科技领域中都有着广泛的应用，由于实际应用需要不同频率的波形，因此设计一个频率可调的信号发生器具有一定的实际意义。
    本文设计的信号发生装置是以STC89C52RC单片机为主控制器，由复位电路、晶振电路、信号产生电路、LED显示电路、滤波电路等构成硬件电路，采用Ｃ语言进行编程，通过DDS技术，根据采样定理并通过单片机控制AD9850芯片，产生频率在0~50MHZ的连续可调正弦波。
本文详细介绍了STC89C52RC 单片机的基本原理，分析了STC89C52RC 各个管脚的功能及它在设计电路中的作用,介绍了芯片AD9850的基本结构及工作原理。最后结合此设计的硬件原理和软件原理，给出了实验结果，并在产生正弦波的基础上又实现了快速扫频功能。

关键字：信号发生器；DDS技术；AD9850；快速扫频
中图分类号：TK514

 
   The design of quick sweep frequency signal generator
Abstract：Also known as signal source or signal generator oscillator, is a very important instrument in the areas of communication, control, medical, teaching, practice and has a wide range of applications in the fields of science and technology in the field, as the actual application requires a different frequency of the wave, so design a frequency signal generator with adjustable has a certain relevance.
Design of signal generator in this article is mainly to STC89C52RC single-chip controller, reset circuit, and oscillator circuits, signal generator, LED display circuit, filter circuit, and so constitute a hardware circuit, using the c programming language, by DDS technologies, according to the sampling theorem and the AD9850 by single-chip computer control chip, adjustable sine wave of frequency 0~50MHZ.
This article details the STC89C52RC single-chip microcomputer principle and analysis STC89C52RC function of each pin and its role in circuit design, describes the basic structure and working principle of chip AD9850. Last principle of binding principles of the design of hardware and software, gives the results, and also enables fast sweep, on the basis of the sine wave function.
Keywords: signal generator ; DDS technologies; AD9850; fast sweep

目 次
摘要 I
目   次 III
１引言 4
1.1 发展背景 4
1.2 研究思路 4
1.3 研究意义 5
2 波形发生器硬件设计 7
2.1 STC89RC52单片机简介 7
2.2 DDS正弦波产生电路 10
2.3低通滤波器的设计 13
2.4 键盘输入显示电路 14
3 软件设计部分 17
3.1系统程序流程 17
3.2 AD9850程序 19
3.3 4×4矩阵键盘子程序设计 21
3.4 数码管显示程序设计 24
3.5 键盘显示转换程序 25
4 系统调试结果及性能分析 29
5 总结 32