【正文】
求學歷程是艱苦的,但又是快樂的。 % 構(gòu)造橢圓濾波器data=filter(b,a,data2)。,2) % 定義超時值Fs = ActualRate。,39。)。Frequency (Hz)39。, 1)。,chan)。)對聲卡產(chǎn)生的模擬輸入對象進行操作。需要注意的是,執(zhí)行完一次數(shù)據(jù)采集工作后應(yīng)刪除設(shè)備對象,將內(nèi)存中的數(shù)據(jù)存儲在硬盤上之后釋放數(shù)據(jù)存儲所占用的內(nèi)存空間,以備下一次采集能有足夠的內(nèi)存空間存儲新的數(shù)據(jù),聲音信號采集的實現(xiàn)程序為clear data1。TriggerConditionValue39。,10000) % 設(shè)置采樣速率為10000HzActualRate = get(AI,39。(5)其他功能。靈活性強。在設(shè)計研究單位和工業(yè)部門,MATLAB被廣泛用于科學研究和解決具體問題。這些同步數(shù)據(jù)可以描述各路信號的相位關(guān)系,所以這種結(jié)構(gòu)被稱為同步型數(shù)據(jù)采集系統(tǒng)。采集速率又稱為系統(tǒng)通過速率或吞吐率,是指在滿足系統(tǒng)精度指標的前提下,系統(tǒng)對輸入的模擬信號在單位時間內(nèi)所能完成的采集次數(shù),或者說是系統(tǒng)每個通道、每秒鐘可采集的有效數(shù)據(jù)的數(shù)量。(1)現(xiàn)代采集系統(tǒng)一般都由計算機控制,使得數(shù)據(jù)采集的質(zhì)量和效率等大為提高,也節(jié)省了硬件投資。 (2)并行式采集(Parallel Acquisition):多個通道同步并行采集,每個通道采用一個獨立的A/D轉(zhuǎn)換器,通道采集速率只取決于A/D的轉(zhuǎn)換速率,與通道數(shù)無關(guān)。首先,分布式控制應(yīng)用場合中的智能數(shù)據(jù)采集系統(tǒng)正在發(fā)展。數(shù)據(jù)采集(Data Acquisition)是將被測對象(外部世界、現(xiàn)場)的各種參量(可以是物理量,也可以是化學量、生物量等)通過各種傳感元件作適當轉(zhuǎn)換后,再經(jīng)信號調(diào)理、采樣、量化、編碼、傳輸?shù)炔襟E,最后送到控制器進行數(shù)據(jù)處理或存儲記錄的過程。關(guān)鍵詞:基于MATLAB;基于聲卡;數(shù)據(jù)采集The System Design Of Data Acquisition Based On The MATLABAbstract:MATLAB has the function of highperformance numerical putation and visual scientific engineering puting. It supports explanatory language input and the sound card, contains rich mathematical functions and has powerful data acquisition toolbox with simple programming. As the MATLAB data collection card, the sound card, pared to the conventional data collection card, endows with a low price, simple development and convenient system. This paper has discussed a design that bines the two kinds to conduct data collection.This paper has specifically introduced the background of this topic, the structure and the characteristics of nowadays data collection system. It has also introduced MATLAB and its data collection toolbox. By using the A/D, D/A conversion technique of the sound card and the function of MATLAB, I have presented a costeffective data collection and analysis design based on the sound card, and analyzed and described thoroughly the course and methods of data collection and analysis system by using MATLAB language programming. Finally, this paper has provided some examples which have applied this data collection system.Key words: Based on MATLAB。數(shù)據(jù)采集技術(shù)已經(jīng)成為一種專門的技術(shù),在工業(yè)領(lǐng)域得到了廣泛的應(yīng)用。(4)變速率變分辨率采樣。 圖2給出了基于MATLAB的數(shù)據(jù)采集系統(tǒng)的簡圖,主要部件數(shù)據(jù)采集工具箱提供了硬件驅(qū)動程序和MATLAB環(huán)境之間“對話”所需的硬件驅(qū)動程序適配器、數(shù)據(jù)采集引擎和M文件函數(shù)。因為系統(tǒng)精度取決于系統(tǒng)的各個環(huán)節(jié)(子系統(tǒng))的精度,如前置放大器、濾波器、模擬多路開關(guān)等。多通道同步數(shù)據(jù)采集系統(tǒng)其結(jié)構(gòu)如圖4所示,也屬于分時轉(zhuǎn)換系統(tǒng)。如果配上數(shù)據(jù)采集線路,該系統(tǒng)就可以作為一個虛擬儀器來使用?;谟嬎銠C聲卡的數(shù)據(jù)采集系統(tǒng)有以下特點。(2)實現(xiàn)將采集到的聲音信號數(shù)據(jù)進行頻譜分析,畫出頻譜圖以圖形方式很直觀地反映出信號特征。chan = addchannel(AI,1)。rising39。 % 設(shè)置采樣速率...% 其它的相關(guān)設(shè)置啟動設(shè)備對象,控制聲卡開始采集數(shù)據(jù),采集過程中可以向聲卡發(fā)送控制命令,如暫停采集、退出采集等。Frequency (Hz)39。)。,)。 % 此函數(shù)為MATLAB自帶 subplot(2,1,2)plot(f,mag)grid on ylabel(39。第 20 頁[參考文獻][1] JI Xiaosong,LI and Realization of Highspeed Data Acquisition Card[J]Modern Electronics ,(1):1618.[2] 陳志勇,[J].計量技術(shù),2010,(1):1215.[3] 李亞微,[J].電聲技術(shù),2007,31(3):1214.[4] 陳小異,劉軍安,[J].新技術(shù)新工藝,2007(10):1011.[5] 王紅兵,王國棟,金翔,[J].物理實驗,2005,(4):2225.[6] 王琳,商周,[J].電測與儀表,2004,(8):1719.[7] 趙祚喜,羅錫文,[J].2003,(3):1316.[8] [J].2003,30(4):912.[9] 賴莉飛,[J].(7):1012.[10] [J].(13):2325.[11] 張金玉,張優(yōu)云,[J].(10):38.[12] VINAY K I。)。)。 % 計算窗函數(shù)長度window = hanning(blocksize)。])致謝行文至此,我的這篇論文已