【正文】 ............................................................................ 3 第 5 章 失真度測量誤差分析 .......................................................................... 1 A/D測量誤差 .................................................................................................. 1 運(yùn)算過程中有限字長效應(yīng)造成的誤差 ............................................... 1 混迭效應(yīng)和頻譜泄漏造成的誤差 ......................................................... 2 基波測量誤差 ................................................................................................. 3 本章小結(jié) ........................................................................................................... 3 第 6 章 總結(jié) ...................................................................................................................... 4 第 2 章 軟件工具介紹 .............................................................................................. 4 結(jié) 論 .............................................................................................................................. 36 致 謝 ................................................................................................ 錯誤 !未定義書簽。頻譜分析法是用頻率分析儀測量各次諧波的方法計算出波形失真度，但采用此種方法的儀器價格較昂貴。因此在信息產(chǎn)生，傳遞，接受過程中，必須認(rèn)真分析處理 好失真問題。 第 I 頁 基于 FPGA 的失真度測試儀 摘 要 在電子工程的設(shè)計和應(yīng)用中，信號無論在開路傳輸或閉路傳輸過程中都受到環(huán)境、傳輸網(wǎng)絡(luò)的工作狀態(tài)和應(yīng)用元器件參數(shù)變化的影響使其或多或少的改變了原有信號的性質(zhì)，這種變化就是所謂的信號畸變現(xiàn)象，通常叫做失真。 通過非線性失真測試可以考察傳輸網(wǎng)絡(luò)的失真性質(zhì)，有利于改進(jìn)傳輸網(wǎng)絡(luò)的性質(zhì)。一般模擬式的測量儀采用基波剔除法，其缺點(diǎn)是需要提供未失真的基波信號而且其低頻測量精度低。 關(guān)鍵詞 ： FFT； FPGA； 失真度 第 II 頁 Abstract In the design and application of electronic engineering， both in open circuit and in closed circuit， signal is certainly affected by environment， the status of the transport work and the change of parameters of the ponent applied. Then the characters of useful information will be changed more or less and the change is generally called as distortion， namely socalled signal distortion. Signal distortion includes three kinds of distortion: frequency， phase and waveform .The waveform distortion ic caused by the nonlinearity of the amplifier circuits it is often called as nonlinearity distortion. The nonlinearity distortion also include harmonic distortion and intermodulation distortion. We can test the charater of the transport newtok by detecting the nonlinear distortion and this is useufl to improve the character of the newtork. In the generation， transport and reception of singal， we must careuflly analyze and handle distortion. Kinds of nonlinear distortion meters have been widely used in many fields such as electronies， electricity and munication， and so distortion meters used in mon generally be divide in tow kinds as the method of theory of test. They are the method of suppressed first frequency and the method of frequeney table analysis. Most of analog distortion meters apply the method of suppressed fisrt frequency. But the disadvantages are need to suppply the first frequency and the lower test precision of the low method of analysis frequency table is using the meter of frequency table to test all kinds of frequency and then calculate the distortion of the wave. But the meter of analysis frequency tbale is more expensive. As the development of microputer and singlechip， especially the DSP chip ， The paper advance a method of measure the disotrtion of sine singal， which is using the DSP chip to carry out the FFT to get the magnitude of all kinds of frequency then using the formula calculate the distortion. The paper fisrt introduce the measure method of generally diostrtion meter of internal and overseas and the application of the meter and secondly pare several measure mehtods， then choose the best method and expound how to carry out this measure method in hardware and sotfware. Using matlab emulate the method and show the result. At the last give the erro analysis of hardware and software during the measurement and the summarize. Keywords: FFT ； FPGA； distortion. 第 III 頁 目 錄 摘 要 .................................................................................................................................I ABSTRACT............................................................................................................................... II 第 1 章 緒 論 ................................................................................................................. 1 本論文的背景和意義 ........................................................................................... 1 失真度測試儀介紹 ............................................................................................... 1 失真度測試儀的發(fā)展?fàn)顩r ................................................................................... 2 技術(shù)指標(biāo) ............................................................................................................... 3 第 2 章 軟件工具介紹 .............................................................................................. 4 FPGA基本知識 .................................................................................................. 4 FPGA 的基本結(jié)構(gòu)簡介 .......................................................................... 4 FPGA 的設(shè)計流程 .................................................................................... 4 QUARTUS II基本知識 ...................................................................................... 8 Quaturs II 的優(yōu)點(diǎn)功能簡介 ............................................................ 4 Quaturs II 設(shè)計流程 .......................................................................... 4 DSP技術(shù)簡介 .......................................................................................... 9 現(xiàn)代 DSP 實(shí)現(xiàn)方案及設(shè)計流程概述 ................................................. 4 基于 FPGA 的 DSP 設(shè)計 ..................................