步階信號 的英文怎麼說
中文拼音 [bùjiēxìnháo]
步階信號
英文
step signal-
Section ii describes the design approach and implementation of speech module on mcf5249 coldfire core. the speech codec optimizes g. 729a codes and added voice activity detection of g. 729b to save bandwidth ; the implementation of acoustic echo cancellation uses nlms algorithm and it can reduce echo though designing adaptive fir filter and speech detector ; the dtmf and cpt generate signal using two second order digital sinusoidal oscillators and detect signal by picking up the frequency information. but only get the frequency information is not enough in cpt detector, this thesis introduces a method
其中對語音編解碼器的設計採用優化g . 729a代碼達到設計要求,並在此基礎上加入g . 729b的靜音檢測模塊,以進一步降低網路傳輸帶寬;對回聲消除器的設計採用nlms演算法,通過設計自適應fir濾波器和語音檢測器達到回聲消除目的;對雙音多頻設計,信號發生端採用構造靜態參數表並通過二階正弦振蕩器產生信號,信號檢測端提取頻率信息以檢測信號;對呼叫進程音設計,除了類似雙音多頻的信號發生及頻率檢測設計外,還需要檢測信號持續時間,作者設計了一種基於匹配狀態表的方法以檢測信號持續時間。This method can reflect local signal feature and well perform in the experiments. we also present an integrated electromyographic signal ( emg ) pattern recognition scheme. the application of an artificial neural network ( ann ) technique together with a feature extraction technique, for the classification of emg signals is described
利用高階譜技術提取肌電信號的特徵信息,然後利用奇異值或者其它方法對二維特徵矩陣進行優化,將優化之後的一維特徵向量輸入神經網路分類器進行模式識別,這種方法能夠初步識別不同模式的上肢運動。What ' s more, some improved carrier synchronization algorithms for high order qam signals are described
最後,討論了適合高階qam信號特點的載波同步方法。Secondly, two carbon fiber reinforced composite beams were fabricated, and their modal frequencies were measured by an experiment method. thirdly, delaminations were modeled by pairs of nodes with the same coordinates but different node numbers, while the modal frequencies of these beams with different delamination location and size were computed by an eas piezoelectric solid element. moreover, a novel method combining computational mechanics and neural network was demonstrated for composite health monitoring ; the first five flexure modal frequencies obtained by fem were modified by a primary revising approach and were used to train the neural network
本文較全面地評述了神經網路的應用模型、改進演算法等,編制了bp神經網路程序:制備了纖維增強復合材料試件,並進行實驗模態分析;利用坐標相同、節點號不同的方法模擬脫層損傷,基於eas列式的壓電固體單元計算了不同脫層損傷情況下的頻率信息;針對基於實驗數據訓練神經網路存在樣本不足的缺陷,本文提出了利用有限元方法對含有脫層損傷的復合材料試件進行數值模擬,以前五階彎曲模態頻率構建訓練樣本的新思路,並提出了一種初步的計算值修正方法,以此構建神經網路的訓練樣本:將實驗模態分析的結果送入訓練好的神經網路進行預測,實現了對復合材料梁的脫層損傷的定位和損傷程度的評估。Based on fourth - order cumulant, a computationally efficient method for joint estimating both directions of arrival and ranges of near field sources with known carrier frequency is firstly presented. the proposed algorithm need not any spectral peak searching and the 2 - d parameters are automatically paired. lt is suitable for arbitrary additive gaussian noise environment. in the following section, a 3 - d esprit method for jointly estimating of frequencies, doa ' s and ranges of multiple near - field sources with unknown carrier frequencies is proposed. the parameters estimation are given by the eigenvalues of different matrices. furthermore, its performances are confirmed by several computer simulations
利用四階累積量,第五章首先給出了一種載頻已知的情況下基於近場源的距離和波達方向聯合估計演算法,通過構造的陣列輸出信號四階累量矩陣使空間信號到達方向和距離估計無需譜峰搜索,且參數自動配對,適合於任意高斯噪聲環境。進一步在第三節提出了一種載頻未知的情況下的多個近場窄帶信號源doa 、距離和頻率聯合估計的3 - desprit演算法。The emphasis of this article is the design in the second period, which is based on the pic microchip interface, because at present embedded structure is adopted by most of medical instruments so that it can run separately without computer, hi this part the article specifically introduces the interface circuit of pic16f877 single - chip, which includes the acquisition of a / d signa ls and the serial communication between the single - chip and computer, the design of complex programmable logic device ( cpld ) and the using of hardware describe language ( vhdl ) to control the rotate speed of 4 - route stepping motors
本論文的重點是在設備的第二階段開發,它是基於pic系列單片機介面的硬體設計,主要是針對現階段大多數醫療設備都是採用嵌入式結構,它能夠脫離計算機單獨運行。在這部分詳細介紹了pic16f877單片機的外圍電路,包括a d信號的採集、單片機與計算機的串列通信,可編程邏輯器件cpld硬體的設計,以及用硬體描述語言vhdl編程來同時實現4路步進電機的轉速控制。The experiment result shows that by adding this modification algorithm into normal fuzzy controller, overshoot of transition process that system responds to the step signal will be further decreased, and convergent speed will be further increased
實驗結論說明,通過在常規模糊控制器加入這種規則校正演算法,可進一步降低系統對階躍輸入信號響應的過渡過程的超調量,並提高的收斂速度。During my studying of postgraduate, i have accomplished above - mentioned researches and results listed below : 1 ) accumulated lots of experimental data of non - contact life - parameter detection system under different conditions, which is a good foundation for the next stage of this research. 2 ) brought forward the method of using adaptive processing to constrain the self - dithering interference. 3 ) brought forward the method of using acceleration sensor to detect the self - dithering interference as the referring signal of the adaptive filter. 4 ) compared the performances of adaptive algorithms based on fssms and vsslms, which is the basis of parameter - setting for applying adaptive processing to constrain the self - dithering interference in this subject. 5 ) constructed the mathematical model between the self - dithering interference and its radar return signal. 6 ) drew the conclusion of that there exists the correlativity between the self - dithering interference and its radar return signal. 7 ) drew the conclusion of that there exists the adding relation between the radar return signal of the self - dithering interference and the detecting signal. 8 ) developed the software for constraining self - dithering interference of non - contact life - parameter detection system
在就讀碩士研究生期間,本人從事以上工作取得的主要研究結果有: l 、積累了大量的不同條件下非接觸生命參數檢測系統的實驗數據,為檢測系統的下一階段研究打下良好的基礎; 2 、提出了採用自適應處理抑制非接觸生命參數檢測系統的自抖動干擾; 3 、提出了採用加速度傳感器檢測非接觸生命參數檢測系統的自抖動干擾作為自適應處理的參考信號: 4 、比較了固定步長和可變步長兩類ms自適應演算法的性能,為自適應演算法應用於本課題的研究提供參數設置依據; 5 、建立了非接觸生命參數檢測系統自抖動和自抖動雷達回波信號之間的數學模型; 6 、得出了非接觸生命參數檢測系統自抖動和自抖動雷達回波信號具有相關性的結論; 7 、得出了非接觸生命參數檢測系統自抖動雷達回波和第二頁第四軍醫大學碩士學位論文檢測信號具有加性關系的結論; 8 、研製了非接觸生命參數檢測系統自抖動干擾抑制軟體。In order to deduce the effects on dynamic performances, a method by using prediction filter is introduced. to minish overshoot subsection of input signal with exponent is adopted. these methods are proved by mathematic simulation
針對動態高型控制方法使系統動態性能變差的問題,提出了利用預測濾波技術改善系統動態性能的方法,進一步提出了利用指數函數將階躍輸入信號分段以降低系統超調量的方法,並通過數學模擬驗證了這兩種方法的有效性。In large rotating machinery using filmatic bearing ( turbogenerator, air compressor, etc. ) there is a potential trouble from impefect installation or running conditions, a metals " contact between rotors and shells. the trouble is usully called rubbing. the advantage of ae technologe in the rubbing diagnosis and early detection is showed. instead of classical ae characteristic parameters ( counts, amplitude, energy, duration and the other ones ) a new feature extraction by frequency analysis of ae envelop signals is discussed. both research of ae process and field experements indicate that periodic components in the envelop spectrum related to rotational speed increase evidently at the beginning of rubbing production, hence are highly sensitive to the rubbing fault diagnosis. according to the new design an acoustic emission equipment for the rubbing diagnosis named buaa ae testing system is developed and described
汽輪發電機、空氣壓縮機等採用油膜支撐的大型轉動機械,由於安裝或運行中的原因,在轉子旋轉過程中,可能和器壁發生輕微的摩擦和碰擊,簡稱碰摩.聲發射技術在碰摩發生特別是故障早期診斷上有優越性.本系統的特點是沒有沿用傳統的計數、幅度、能量和持續時間等聲發射特性參數,而是在聲發射包絡信號的頻率分析中進行特徵提取.聲發射發生的過程分析和現場試驗都表明這種方法對碰摩檢測很敏感,在碰摩發生的起始階段,包絡譜中與轉速同步的周期性分量顯著增加.根據這種新的設計思想自行研製了buaa碰摩聲發射檢測儀並對此作了介紹This is by two reasons : the first, as the development of military communication technologies, it transit from digital to software implementation, intelligence, broad band implementation and network implementation. many new technologies such as adaptive frequency hopping, burst communication, broadband modulation and complex coding accelerate the research about pertinence algorithms of signal sense and signal processing. the second, three hotspots of modern signal processing - spectrum estimation, high - order statistics ( hos ) and time - frequency analysis theory become more and more consummately and being used in communication jamming and anti - jamming field
應用於軍事通信對抗的信號處理理論發展非常迅速,這得益於兩個方面的動力:其一,軍事通信的技術和手段不斷更新,在數字化的基礎上逐步走向軟體化、智能化、寬帶化和網路化,出現了自適應跳頻、突發通信、寬帶調制和復雜編碼等新的實用技術,推動了具有很強針對性的信號偵測和處理領域的演算法研究;其二,現代信號處理的三大熱點? ?譜估計、高階統計量方法、時頻分析的理論和技術日臻完善,並逐漸應用於通信對抗領域。Take the hoc based blind modulation detection algorithm as an example, the relationship between the blind modulation detection algorithm and synchronization is investigated. an unproved detection algorithm robust to frequency offset is proposed which solves the problem caused by the error in carrier synchronization. how to synchronize a received signal with unknown modulation type is studied and a blind algorithm to estimate symbol timing of the signals with unknown modulation type is presented
研究了載波同步和碼元定時同步與調制方式盲檢測演算法的關系;以自適應單載波中高階累積量調制方式盲檢測演算法為例,對于載波同步誤差引起的頻偏問題,提出一種基於頻偏穩健的mdpsk信號調制方式盲檢測演算法;對于未知調制方式信號的定時同步問題,提出一種盲定時估計演算法,該演算法可以估計mdpsk和mqam信號的定時同步信息,實現數字信號的同步分類;提出了一種基於調制方式盲檢測的自適應接收機結構,把調制方式盲檢測,信噪比估計和同步解調聯合起來進行,實現調制方式隨通道質量而自適應變化的信號的正確接收。The control system adopts high capability singlechip, aduc812 ( 8052 - compatible core ). it can expediently achieve a / d ( 12bit ), d / a ( 12bit ), phase compensation of the rotor position singles, and speed closed - loop control, and fully resolves the well - off switch from the out - synchronization to the in - synchronization. the practical prototype of the system is developed for the control of a dentist " sensorless brushless dc drill motor
系統採用高性能aduc812 (兼容8052內核)單片機作為微處理器,方便的實現a / d ( 12位) 、 d / a ( 12位) 、電機轉子位置信號相位檢測與補償以及系統速度閉環控制,很好地解決了無位置傳感器bldcm從外同步運行階段到內同步運行階段的順利切換。分享友人