外文翻譯--數(shù)字濾波器的仿真與實(shí)現(xiàn)

1、<p><b>　　鄭州輕工業(yè)學(xué)院</b></p><p>　　畢業(yè)設(shè)計(jì)(論文)外文資料翻譯</p><p>　　附件：1.外文資料翻譯譯文（約3000漢字）；</p><p>　　2.外文資料原文(與課題相關(guān)的1萬印刷符號左右)。</p><p><b>　　英文原文</b></p

2、><p>　　The simulation and the realization of the digital filter</p><p>　　With the information age and the advent of the digital world, digital signal processing has become one of today's most i

3、mportant disciplines and door technology. Digital signal processing in communications, voice, images, automatic control, radar, military, aerospace, medical and household appliances, and many other fields widely applied.

4、 In the digital signal processing applications, the digital filter is important and has been widely applied.</p><p>　　1、 figures Unit on :</p><p>　　Analog and digital filters</p><p>

5、;　　In signal processing, the function of a filter is to remove unwanted parts of the signal, such as random noise, or to extract useful parts of the signal, such as the components lying within a certain frequency range.

6、</p><p>　　The following block diagram illustrates the basic idea. </p><p>　　There are two main kinds of filter, analog and digital. They are quite different in their physical makeup and in how t

7、hey work. An analog filter uses analog electronic circuits made up from components such as resistors, capacitors and op amps to produce the required filtering effect. Such filter circuits are widely used in such applic

8、ations as noise reduction, video signal enhancement, graphic equilibrium in hi-fi systems, and many other areas. There are well-established standard techniques fo</p><p>　　Note that in a digital filter, the

9、signal is represented by a sequence of numbers, rather than a voltage or current. </p><p>　　The following diagram shows the basic setup of such a system. </p><p>　　Unit refers to the input sign

10、als used to filter hardware or software. If the filter input, output signals are separated, they are bound to respond to the impact of the Unit is separated, such as digital filters filter definition. Digital filter func

11、tion, which was to import sequences X transformation into export operations through a series Y.</p><p>　　According to figures filter function 24-hour live response characteristics, digital filters can be div

12、ided into two, namely, unlimited long live long live the corresponding IIR filter and the limited response to FIR filters. IIR filters have the advantage of the digital filter design can use simulation results, and simul

13、ation filter design of a large number of tables may facilitate simple. It is the shortcomings of the nonlinear phase; Linear phase if required, will use the entire network phase-</p><p>　　FIR filters can be

14、strictly linear phase, but because the system FIR filter function extremity fixed at the original point, it can only use the higher number of bands to achieve their high selectivity for the same filter design indicators

15、FIR filter called band than a few high-IIR 5-10 times, the cost is higher, Signal delay is also larger. But if the same linear phase, IIR filters must be network-wide calibration phase, the same section also increase the

16、 number of filters and net work complexit</p><p>　　Unit from sub-functions can be divided into the following four categories :</p><p>　　(1) Low-filter (LPF);</p><p>　　(2) high-filte

17、r (HPF);</p><p>　　(3) belt-filter (BPF); </p><p>　　(4) to prevent filter (BSF).</p><p>　　The following chart dotted line for the ideals of the filter frequency characteristics :<

18、/p><p>　　2、 MATLAB introduced</p><p>　　MATLAB is a matrix laboratory (Matrix Laboratory) is intended. In addition to an excellent value calculation capability, it also provides professional symbols

19、 terms, word processing, visualization modeling, simulation and real-time control functions. MATLAB as the world's top mathematical software applications, with a strong engineering computing, algorithms research, eng

20、ineering drawings, applications development, data analysis and dynamic simulation, and other functions, in aerospace, mechanic</p><p>　　In the electricity system protection and secondary computer control, ma

21、ny signal processing and analysis are based on are certain types sinusoidal wave and the second harmonics of the system voltage and current signals (especially at D process), are mixed with a variety of complex component

22、s, the filter has been installed power system during the critical components. Current computer protection and the introduction of two digital signal processing software main filter. Digital filter design using</p>

23、<p>　　MATLAB is the basic unit of data matrix, with its directives expression mathematics, engineering, commonly used form is very similar, it is used to solve a problem than in MATLAB C, Fortran and other language

24、s End precision much the same thing. The popular MATLAB 5.3/Simulink3.0 including hundreds of internal function with the main pack and 30 types of tool kits (Toolbox). kits can be divided into functional tool kits and di

25、sciplines toolkit. MATLAB tool kit used to expand the functional symbols</p><p>　　MATLAB users to open widely welcomed. In addition to the internal function, all the packages MATLAB tool kits are readable do

26、cument and the document could be amended, modified or users through original program the construction of new procedures to prepare themselves for kits.</p><p>　　3、 Digital filter design</p><p>　

27、　Digital filter design of the basic requirements</p><p>　　Digital filter design must go through three steps :</p><p>　　(1) Identification of indicators : In the design of a filter, there must be

28、 some indicators. These indicators should be determined on the basis of the application. In many practical applications, digital filters are often used to achieve the frequency operation. Therefore, indicators in the for

29、m of general jurisdiction given frequency range and phase response. Margins key indicators given in two ways. The first is absolute indicators. It provides a function to respond to the demands of the gener</p><

30、;p>　　(2) Model approach : Once identified indicators can use a previous study of the basic principles and relationships, a filter model to be closer to the target system.</p><p>　　(3) Achieved : the resul

31、ts of the above two filters, usually by differential equations, system function or pulse response to describe. According to this description of hardware or software used to achieve it.</p><p>　　4、Introductio

32、n of DSP</p><p>　　Today, DSP is widely used in the modern techno logy and it has been the key part of many products and played more and mo re important role in our daily life Recently, Northwestern Poly tech

33、nical University Aviation Microelectronic Center has completed the design of digital signal processor co re NDSP25, which is aiming at TM S320C25 digital signal processor of Texas Instrument TM S320 series. By using top

34、2dow n design flow NDSP25 is compatible with instruction and interface timing of TM S320C25</p><p>　　Digital signal processors (DSP) is a fit for real-time digital signal processing for high-speed dedicated

35、processors, the main variety used for real-time digital signal processing to achieve rapid algorithms. In today's digital age background, the DSP has become the communications, computer, and consumer electronics prod

36、ucts, and other fields based device.</p><p>　　Digital signal processors and digital signal processing is inseparably, we usually say "DSP" can also mean the digital signal processing (Digital Signa

37、l Processing), is that in this digital signal processors Lane. Digital signal processing is a cover many disciplines applied to many areas and disciplines, refers to the use of computers or specialized processing equipme

38、nt, the signals in digital form for the collection, conversion, recovery, valuation, enhancement, compression, identification, pr</p><p><b>　　中文翻譯</b></p><p>　　數(shù)字濾波器的仿真與實(shí)現(xiàn)</p>

39、<p>　　隨著信息時代和數(shù)字世界的到來，數(shù)字信號處理已成為當(dāng)今一門極其重要的學(xué)科和技術(shù)領(lǐng)域。數(shù)字信號處理在通信、語音、圖像、自動控制、雷達(dá)、軍事、航空航天、醫(yī)療和家用電器等眾多領(lǐng)域得到了廣泛的應(yīng)用。在數(shù)字信號處理應(yīng)用中，數(shù)字濾波器十分重要并已獲得廣泛應(yīng)用。</p><p>　　1、數(shù)字濾波器介紹：</p><p><b>　　模擬和數(shù)字濾波器 </b>&

40、lt;/p><p>　　在信號處理、過濾功能是一個不排除部分信息,如隨機(jī)噪音、提取有用的信號部分,如部分地勢在一定的頻率范圍. </p><p>　　以下方框圖說明基本思路. </p><p>　　有兩大類型的過濾, 模擬 以及 數(shù)字 . 他們是完全不同的物理結(jié)構(gòu),如何工作. 類比電子電路模擬用的過濾部分組成,例如由電阻、電容、放大器和生產(chǎn)所需的過濾效果. 這種過濾器被

41、廣泛使用的電路減少噪音等方面的應(yīng)用,提高視頻信號、圖像均衡的高科技傳真系統(tǒng)等眾多領(lǐng)域. 有完善的技術(shù)標(biāo)準(zhǔn)設(shè)計(jì)的模擬電路進(jìn)行過濾特定要求. 在各個階段,是一個信號,是電機(jī)電壓和過濾,目前直接的物理模擬量(例如聲音或視頻信號和變頻器生產(chǎn))處理. 數(shù)碼過濾用數(shù)字進(jìn)行數(shù)值計(jì)算處理器的信號抽樣值. 處理器的可能通用計(jì)算機(jī)等PC或?qū)I(yè)發(fā)展計(jì)劃圖(數(shù)字信號處理器)芯片. 模擬信號必須先投入使用的取樣和數(shù)碼藝術(shù)發(fā)展局(模擬到數(shù)字轉(zhuǎn)換器). 由此二元多,

42、占抽樣連續(xù)輸入信號的價值,轉(zhuǎn)移到處理器,進(jìn)行數(shù)字計(jì)算. 這些計(jì)算通常涉及多方面的投入和增加產(chǎn)品價值的共同因素. 如有必要,這些計(jì)算結(jié)果,現(xiàn)在是抽樣信號值的過濾,產(chǎn)出通過發(fā)展援助委員會(類比數(shù)位轉(zhuǎn)換器來)信號轉(zhuǎn)換回模擬形式. </p><p>　　看到一個數(shù)字過濾,信號是由一系列數(shù)字,而不是電壓或逆流. </p><p>　　以下圖表顯示了這種制度的基本格局：</p><

43、p>　　濾波器是指用來對輸入信號進(jìn)行濾波的硬件或軟件。如果濾波器的輸入、輸出</p><p>　　都是離散信號，則該濾波器的沖擊響應(yīng)也必然是離散的，這樣的濾波器定義為數(shù)字濾波器。數(shù)字濾波器的功能，就是把輸入序列X通過一定的運(yùn)算變換成輸出序列Y。</p><p>　　根據(jù)數(shù)字濾波器沖激響應(yīng)函數(shù)的時域特性，可將數(shù)字濾波器分為兩種，即無限長沖激相應(yīng)IIR濾波器和有限長沖激響應(yīng)FIR濾波器。

44、IIR數(shù)字濾波器的優(yōu)點(diǎn)是可以利用模擬濾波器設(shè)計(jì)的結(jié)果，而模擬濾波器的設(shè)計(jì)有大量圖表可查，方便簡單。它的缺點(diǎn)是相位的非線性；若需要線性相位，則要采用全通網(wǎng)絡(luò)進(jìn)行相位校正。圖象處理以及數(shù)據(jù)采集傳輸都要求濾波器具有線性相位特性。而FIR數(shù)字濾波器可以實(shí)現(xiàn)線性相位，又可具有任意幅度特性。從數(shù)字濾波器的單位沖擊響應(yīng)來看，可分為兩大類：有限沖擊響應(yīng)（FIR）數(shù)字濾波器和無限沖擊響應(yīng)（IIR）數(shù)字濾波器。</p><p>　　

45、FIR濾波器卻可以得到嚴(yán)格的線性相位，然而由于FIR濾波器的系統(tǒng)函數(shù)的極點(diǎn)固定在原點(diǎn)，所以只能用較高的階數(shù)來實(shí)現(xiàn)其高選擇性，對于同樣的濾波器設(shè)計(jì)指標(biāo)，F(xiàn)IR濾波器所要求的階數(shù)要比IIR高5至10倍，所以成本較高，信號延遲也較大。但是如果要求相同的線性相位，則IIR濾波器就必須加全通網(wǎng)絡(luò)進(jìn)行相位校正，同樣也要增加濾波器網(wǎng)絡(luò)的節(jié)數(shù)和復(fù)雜性。FIR濾波器可以用非遞歸的方法實(shí)現(xiàn)，在有限精度下不會產(chǎn)生振蕩，同時由于量化舍入以及系數(shù)的不確定性所引起

46、的誤差的影響要比IIR濾波器小的多，并且FIR濾波器可以采用FFT算法，運(yùn)算速度快。但是不象IIR濾波器可以借助模擬濾波器的成果，F(xiàn)IR濾波器沒有現(xiàn)成的計(jì)算公式，必須要用計(jì)算機(jī)輔助設(shè)計(jì)軟件（如MATLAB）來計(jì)算。由此可知，F(xiàn)IR濾波器應(yīng)用比較廣，而IIR濾波器則用在相位要求不是很嚴(yán)格的場合。</p><p>　　濾波器從功能上分又可分為如下4類:</p><p>　　(1)低通濾波器(L

47、PF)；</p><p>　　(2)高通濾波器(HPF )；</p><p>　　(3)帶通濾波器(BPF )；</p><p>　　(4)帶阻濾波器(BSF)。</p><p>　　理想濾波器的幅頻特性下圖虛線為：</p><p>　　2、MATLAB介紹：</p><p>　　MATLAB是

48、矩陣實(shí)驗(yàn)室（Matrix　Laboratory）之意。除具備卓越的數(shù)值計(jì)算能力外，它還提供了專業(yè)水平的符號計(jì)算，文字處理，可視化建模仿真和實(shí)時控制等功能。MATLAB作為世界頂尖的數(shù)學(xué)應(yīng)用軟件，以其強(qiáng)大的工程計(jì)算、算法研究、工程繪圖、應(yīng)用程序開發(fā)、數(shù)據(jù)分析和動態(tài)仿真等功能，在航空航天、機(jī)械制造和工程建筑等領(lǐng)域發(fā)揮著越來越重要的作用。而C語言功能豐富，使用靈活方便，目標(biāo)程序效率高。既有高級語言的優(yōu)點(diǎn)，又有低級語言的特點(diǎn)。因此，C語言是目前

49、應(yīng)用最廣的編程語言。雖然MATLAB是一個完整的、功能齊全的編程環(huán)境，但在某些情況下，與外部環(huán)境的數(shù)據(jù)和程序的交互是非常必須而且有益的。利用MATLAB設(shè)計(jì)濾波器，可以隨時對比設(shè)計(jì)要求和濾波器特性調(diào)整參數(shù)，直觀簡便，極大的減輕了工作量，有利于濾波器設(shè)計(jì)的最優(yōu)化。</p><p>　　在電力系統(tǒng)微機(jī)保護(hù)和二次控制中，很多信號的處理與分析都是基于正旋基波和某些整次諧波而進(jìn)行的，而系統(tǒng)電壓電流信號（尤其是故障瞬變過程）

50、中混有各種復(fù)雜成分，所以濾波器一直是電力系統(tǒng)二次裝置的關(guān)鍵部件。目前微機(jī)保護(hù)和二次信號處理軟件主要采用數(shù)字濾波器。傳統(tǒng)的數(shù)字濾波器設(shè)計(jì)使用繁瑣的公式計(jì)算，改變參數(shù)后需要重新計(jì)算，在設(shè)計(jì)濾波器尤其是高階濾波器時工作量很大。利用MATLAB信號處理箱可以快速有效地實(shí)現(xiàn)數(shù)字濾波器的設(shè)計(jì)與仿真。</p><p>　　MATLAB的基本數(shù)據(jù)單位是矩陣，它的指令表達(dá)式與數(shù)學(xué),工程中常用的形式十分相似,故用MATLAB來解算問

51、題要比用C,FORTRAN等語言完相同的事情簡捷得多.當(dāng)前流行的MATLAB 5.3/Simulink3.0包括擁有數(shù)百個內(nèi)部函數(shù)的主包和三十幾種工具包(Toolbox)。工具包又可以分為功能性工具包和學(xué)科工具包.功能工具包用來擴(kuò)充MATLAB的符號計(jì)算,可視化建模仿真,文字處理及實(shí)時控制等功能.學(xué)科工具包是專業(yè)性比較強(qiáng)的工具包,控制工具包,信號處理工具包,通信工具包等都屬于此類。</p><p>　　開放性使M

52、ATLAB廣受用戶歡迎.除內(nèi)部函數(shù)外,所有MATLAB主包文件和各種工具包都是可讀可修改的文件,用戶通過對源程序的修改或加入自己編寫程序構(gòu)造新的專用工具包。</p><p>　　3、數(shù)字濾波器的設(shè)計(jì)</p><p>　　數(shù)字濾波器設(shè)計(jì)的基本要求</p><p>　　數(shù)字濾波器設(shè)計(jì)要經(jīng)過三個步驟：</p><p>　?。?）確定指標(biāo)：在設(shè)計(jì)一個

53、濾波器前，必須有一些指標(biāo)。這些指標(biāo)要根據(jù)應(yīng)用確定。在很多實(shí)際應(yīng)用中，數(shù)字濾波器常常被用來實(shí)現(xiàn)選頻操作。因此，指標(biāo)的形式一般在頻域中給出幅度和相位響應(yīng)。幅度指標(biāo)主要以兩種方式給出。第一種是絕對指標(biāo)。它提供對幅度響應(yīng)函數(shù)的要求，一般應(yīng)用于FIR濾波器的設(shè)計(jì)。第二種指標(biāo)是相對指標(biāo)。它以分貝值的形式給出要求。在工程實(shí)際中，這種指標(biāo)最受歡迎。對于相位響應(yīng)指標(biāo)形式，通常希望系統(tǒng)在通頻帶中人有線性相位。運(yùn)用線性相位響應(yīng)指標(biāo)進(jìn)行濾波器設(shè)計(jì)具有如下優(yōu)點(diǎn)：

54、①只包含實(shí)數(shù)算法，不涉及復(fù)數(shù)運(yùn)算；②不存在延遲失真，只有固定數(shù)量的延遲；③長度為N的濾波器（階數(shù)為N-1），計(jì)算量為N/2數(shù)量級。</p><p>　?。?）模型逼近：一旦確定了指標(biāo)，就可利用前面學(xué)習(xí)過的基本原理和關(guān)系式，提出一個濾波器模型來逼近給定的指標(biāo)體系。</p><p>　?。?）實(shí)現(xiàn)：上面兩步的結(jié)果得到的濾波器，通常是以差分方程、系統(tǒng)函數(shù)或脈沖響應(yīng)來描述的。根據(jù)這個描述用硬件或者

55、計(jì)算機(jī)軟件來實(shí)現(xiàn)它。</p><p><b>　　4、DSP簡介</b></p><p>　　今天，DSP廣泛應(yīng)用于現(xiàn)代技術(shù)中，它已是許多產(chǎn)品的關(guān)鍵部分，在我們?nèi)粘Ｉ钪邪缪葜絹碓街匾慕巧Ｗ罱?，系西北工業(yè)大學(xué)Aviation微電子研究中心完成了數(shù)字信號處理器的核心NDSP25的設(shè)計(jì)，它是以TexasTms320系列為指導(dǎo)來完成TMS320C25的數(shù)字信號處理器設(shè)

56、計(jì)的目標(biāo)，通過用一低端設(shè)計(jì)流，NDSP25兼容了TMS320C25的時間界面和指導(dǎo)內(nèi)容。</p><p>　　數(shù)字信號處理器(Digital Signal Processor)是一種適合對數(shù)字信號進(jìn)行高速實(shí)時處理的專用處理器，其主要用來實(shí)時快速地實(shí)現(xiàn)各種數(shù)字信號處理算法。在當(dāng)今的數(shù)字化時代背景下，DSP已成為通信、計(jì)算機(jī)、消費(fèi)類電子產(chǎn)品等領(lǐng)域的基礎(chǔ)器件。</p><p>　　數(shù)字信號處理器

57、與數(shù)字信號處理有著密不可分的關(guān)系，我們通常說的“DSP”也可以指數(shù)字信號處理(Digital Signal Processing )，在本文里都是指數(shù)字信號處理器。數(shù)字信號處理是一門包括了許多學(xué)科并應(yīng)用于很多領(lǐng)域的學(xué)科，是指利用計(jì)算機(jī)或是專用處理設(shè)備，以數(shù)字形式對信號進(jìn)行采集、變換、濾波、估值、增強(qiáng)、壓縮、識別等處理，得到符合要求的信號形式。數(shù)字信號處理器是用于處理數(shù)字信號的器件，因此它是伴隨著數(shù)字信號處理才產(chǎn)生的。</p>

58、<p>　　DSP發(fā)展歷程大致分為三個階段：20世紀(jì)70年代理論先行，80年代產(chǎn)品普及和90年代的突飛猛進(jìn)。在DSP出現(xiàn)之前數(shù)字信號處理只能依靠微處理器(MPU)來完成。但MPU較低的處理速度無法滿足高速實(shí)時的要求。因此，直到20世紀(jì)70年代，有人才提出了DSP的理論和算法基礎(chǔ)。隨著大規(guī)模集成電路技術(shù)的發(fā)展，1982年世界上誕生了首枚DSP芯片。幾年后，第二代基于CMOS工藝的DSP芯片應(yīng)運(yùn)而生。80年代后期，第三代DSP

59、芯片問世。90年代DSP發(fā)展最快，相繼出現(xiàn)了第四代和第五代DSP器件。經(jīng)過20多年的發(fā)展，DSP產(chǎn)品的應(yīng)用已擴(kuò)大到人們的學(xué)習(xí)、工作和生活的各個方面，并逐漸成為電子產(chǎn)品更新?lián)Q代的決定因素。</p><p>　　作者：Sanjit K.Mitra </p><p><b>　　國籍：USA </b></p><p>