【正文】 .....................................................21 總體設(shè)計(jì)要求 ..................................................................................................................21 濾波器設(shè)計(jì) ......................................................................................................................22III 仿真實(shí)現(xiàn) ..........................................................................................................................24 本章小結(jié) ............................................................................................................................26第 3 章 抽取器 VHDL 語言實(shí)現(xiàn) ...............................................................................................27 信號發(fā)生模塊 ....................................................................................................................27 CIC 濾波器模塊 .................................................................................................................29 ISOP 補(bǔ)償濾波器模塊 .......................................................................................................32 第一級 HB 濾波器模塊 .....................................................................................................33 第二級 HB 濾波器模塊 .....................................................................................................34 FIR 濾波器模塊 .................................................................................................................37 總體設(shè)計(jì) ............................................................................................................................38 本章小結(jié) ............................................................................................................................40第 4 章 抽取器硬件調(diào)試 ............................................................................................................41 硬件平臺(tái)介紹 ....................................................................................................................41 調(diào)試過程 ............................................................................................................................42 結(jié)果分析 ............................................................................................................................48 本章小結(jié) ............................................................................................................................49第 5 章 總結(jié)與展望 ....................................................................................................................50參考文獻(xiàn) ............................................................................................................................................51附錄 ....................................................................................................................................................53致謝 ....................................................................................................................................................61IV圖列圖 11 設(shè)計(jì)結(jié)構(gòu)圖 ..............................................................................................................................4圖 21 抽取器 ......................................................................................................................................5圖 22 信號抽取示意圖 ......................................................................................................................6圖 23 抽取前后的頻譜結(jié)構(gòu)（混疊） ..............................................................................................7圖 24 抽取前后的頻譜結(jié)構(gòu)（無混疊） ..........................................................................................7圖 25 FIR 濾波器設(shè)計(jì) .....................................................................................................................11圖 26 FIR 濾波器的基本結(jié)構(gòu) .........................................................................................................11圖 27 半帶濾波器頻譜特性及 2 倍抽取時(shí)的混疊情況 ................................................................13圖 28 31 階半帶濾波器頻率響應(yīng) ...................................................................................................14圖 29 單級 CIC 濾波器的實(shí)現(xiàn) .......................................................................................................15圖 210 多級 CIC 濾波器的實(shí)現(xiàn) .....................................................................................................15圖 211 CIC 濾波器的頻率響應(yīng) .......................................................................................................16圖 212 ISOP 補(bǔ)償濾波器前后通帶內(nèi)波紋 .....................................................................................18圖 213 抽取的多項(xiàng)分解 ..................................................................................................................19圖 214 多相抽取 前后頻譜對比 ......................................................................................................20圖 215 32 倍抽取濾波器組 .............................................................................................................21圖 216 第一級 HB 濾波器頻率響應(yīng) ..............................................................................................22圖 217 測試信號的時(shí)域波形及頻譜 ..............................................................................................24圖 218 原信號和輸出信號的時(shí)域波形 ..........................................................................................25圖 219 原信號和輸出信號的頻譜 ..................................................................................................25圖 220 通過 CIC 濾波器后的時(shí)域波形和頻譜 .............................................................................26圖 31 信號發(fā)生模塊設(shè)計(jì)框圖 ........................................................................................................28圖 32 信號發(fā)生模塊仿真圖 ............................................................................................................28圖 33 CIC 濾波器模塊設(shè)計(jì)理框圖 .................................................................................................31圖 34 CIC 濾波器模塊仿真圖 ..................................