【正文】 唐 山 學(xué) 院畢 業(yè) 設(shè) 計設(shè)計題目：基于 DDS 技術(shù)的信號發(fā)生器的設(shè)計與實現(xiàn) 系 別： 信息工程系 2022 年 6 月 10 日基于 DDS 技術(shù)的信號發(fā)生器的設(shè)計與實現(xiàn)摘 要DDS 是直接數(shù)字式頻率合成器（Direct Digital Synthesizer）的英文縮寫。與傳統(tǒng)的頻率合成器相比，DDS 具有低成本、低功耗、高分辨率和快速轉(zhuǎn)換時間等優(yōu)點，廣泛使用在電信與電子儀器領(lǐng)域，是實現(xiàn)設(shè)備全數(shù)字化的一個關(guān)鍵技術(shù)。本設(shè)計采用單片機(jī)為核心處理器，利用鍵盤輸入信號的參數(shù)，控制 DDS 的AD9850 模塊產(chǎn)生信號，信號的參數(shù)在 LCD1602 上顯示，完成正弦信號和方波信號的輸出，用示波器輸出驗證。DDS 是一種全數(shù)字化的頻率合成器，由相位累加器、波形 ROM、D/A 轉(zhuǎn)換器和低通濾波器構(gòu)成。時鐘頻率給定后，輸出信號的頻率取決于頻率控制字，頻率分辨率取決于累加器位數(shù)，相位分辨率取決于 ROM 的地址線位數(shù)，幅度量化噪聲取決于 ROM 的數(shù)據(jù)位字長和 D/A 轉(zhuǎn)換器位數(shù)。與傳統(tǒng)的頻率合成方法相比，DDS 合成信號具有頻率切換時間短、頻率分辨率高、相位變化連續(xù)等諸多優(yōu)點。使用單片機(jī)靈活的控制能力與 AD9850 的高性能、高集成度相結(jié)合，可以克服傳統(tǒng) DDS 設(shè)計中的不足，從而設(shè)計開發(fā)出性能優(yōu)良的信號發(fā)生器系統(tǒng)。關(guān)鍵詞：單片機(jī) 直接數(shù)字頻率合成 AD9850 DDSDesign and Implementation of the Signal Generator Based on DDS TechnologyAbstractDDS is Direct Digital frequency Synthesizer (Direct Digital Synthesizer) English abbreviations. Compared with the traditional frequency synthesizer, with low cost, DDS low power consumption, high resolution and fast converting speed time and so on, widely used in telemunications and electronic instruments field, is to realize equipment full digital a key technology. This design uses the single chip processor as the core, using a keyboard input signal parameters, control of DDS AD9850 module produce signals, the signal parameters in LCD1602 show that the plete sine signal and square wave signal output, the output with an oscilloscope validation. DDS is A full digital frequency synthesizer, by phase accumulators, waveform ROM, D/A converter and low pass filter position. The clock frequency after A given, the output depends on the frequency of the signal frequency control word, the frequency resolution depends on accumulators digits, phase resolution depends on the ROM address line digits, amplitude quantization noise depends on the ROM data A word length and D/A converter digits. And the frequency of the traditional method than the synthesis, DDS synthesis signal has a frequency switching frequency of short time, high resolution and continuous phase changes, and many other advantages. Using single chip microputer control of the flexible ability and high performance, high level of integration of the AD9850 bination, can overe the disadvantage of the traditional DDS design, to design the developed good performance of signal generator system. Key word: MCU。 direct digital frequency synthesis。AD9850。DDS目 錄1 引言 .................................................................................................................................12 DDS 概要 .........................................................................................................................2 DDS 介紹 ...................................................................................................................2 DDS 結(jié)構(gòu) ..........................................................................................................2 典 型 的 DDS 函 數(shù) 發(fā) 生 器 ..............................................................................3 DDS 數(shù)學(xué)原理 ...........................................................................................................53 總體設(shè)計方案 .................................................................................................................8 系統(tǒng)設(shè)計原理 ...........................................................................................................8 總體設(shè)計框圖 ...........................................................................................................84 系統(tǒng)硬件模塊的組成 .....................................................................................................9 單片機(jī)控制模塊 .......................................................................................................9 STC89C52 主要性能 ........................................................................................9 STC89C52 功能特性描述 ................................................................................9 時鐘電路 ........................................................................................................11 復(fù)位電路 .........................................................................................................11 AD9850 模塊 ........................................................................................................12 AD9850 簡介 ..................................................................................................12 AD9850 的控制字與控制時序 ......................................................................14 單片機(jī)與 AD9850 的接口 .............................................................................15 濾波電路設(shè)計 .........................................................................................................15 鍵盤控制模塊 .........................................................................................................16 LCD 顯示模塊 .........................................................................................................16 液晶顯示器顯示原理 .....................................................................................16 1602LCD 引腳與時序 ....................................................................................17 A/D 轉(zhuǎn)換模塊 ..........................................................................................................205 軟件設(shè)計與調(diào)試 ...........................................................................................................21 程序流程圖 .............................................................................................................21 軟件調(diào)試 .................................................................................................................22 keil 編程工具介紹 ..........................................................................................22 STCISP 下載工具介紹 .................................................................................236 硬件電路制作 ...............................................................................................................24 原理圖