field modulation 中文意思是什麼

field modulation 解釋
場調制
  • field : n 菲爾德〈姓氏〉。n 1 原野,曠野;(海、空、冰雪等的)茫茫一片。2 田地,牧場;割草場;〈pl 〉〈集...
  • modulation : n 調整,調節;(聲調的)抑揚,變化;【音樂】轉調,變調;【無線電】調制。 amplitude modulation 振...
  1. Modulation doped field effect transistor modfet

    調制雜場效應管
  2. This paper starts the research of the liquid floated pendulous accelerometer testing system according to the engineering. at first, this paper gives the brief introduction of the history and present status of accelerometer and its testing technology, the working principium and math model of the liquid floated pendu - lous accelerometer, and then, decides the binary width pulse force retrim loop as the design proposal of testing system, researches the transfer function of every part in the system emphasizly, analyses the stability of the whole accelerometer testing system from the angle of control theoretics by the open loop transfer function of system, and designed the correcting net, analyses the basal problems such as resolution, sampling restraint, precision and so on, designs the hardware testing circuits such as preamplification, band - pass filter, alternating amplifier, phase sensitive demodulatorn, pulse - width modulation, frequency scale circuit, moment current generator. finally, using the graphics program language labv - iew which is designed for testing field especially by ni accomplishes the solfware design of testing system, realized the testing functions

    首先對加速度計及其測試技術的發展歷史和現狀,液浮擺式加速度計的工作原理和數學模型等作了簡要的介紹,然後確定了以二元調寬脈沖再平衡測試迴路為設計方案,並從控制理論的角度進行了分析,著重研究了系統中各部分的傳遞函數,利用系統開環傳遞函數分析了系統的穩定性,同時設計了系統的校正網路;分析了二元調寬脈沖再平衡測試迴路的解析度、采樣約束以及測試精度等基本問題,並按照系統分析的結果設計了包括前置放大、帶通濾波、交流放大、相敏解調、脈寬調制、頻標電路以及力矩電流發生器等測試系統各部分硬體電路,驗證了電路的正確性,最後按照測試系統的要求,採用了美國ni公司專為測試領域所開發的虛擬儀器工具? ? labview作為測試軟體開發工具,利用該圖形化編程語言完成了測試系統軟體部分的設計,實現了測試功能。
  3. Presents the model proposed for analyzing the vibration characteristics of shrouded blades and their calculation method by employing a wave propagation theory and modal synthesis technology coupled with a finite element method from the view point it is possible not only to conduct frequency modulation of the shrouded blades of a gas turbine, but also to utilize the friction effects between them to dissipate energy, thereby attaining the aim of vibration alleviation, as shrouded blades have been widely used in the design of high - speed turbomachinery, such as modern gas turbines and steam turbines, and with the shrouded blades forming an integral whole in a centrifugal force field, the vibration characteristics of the whole ring of blades are different from those of a single isolated blade, and this makes it essential to take into account the integral effect of blade shrouds, concludes from the calculation examples and engineering application that the above approach is valid and correct along with the possibility of considerably reducing the scale of calculation and analysis, and points out it is necessary to take into consideration the coupled effect of the whole ring of blades while the dynamic characteristics of shrouded blades is being analysed

    帶冠葉片不但能調頻,還可以利用葉冠之間的摩擦效應來耗散能量,達到減振的目的.帶冠葉片在離心力場中形成一整體,其整圈葉片振動特性不同於單個孤立葉片,需考慮葉冠的整體效應.利用帶冠葉片系統的循環對稱性,提出了採用波傳播理論和模態綜合技術,結合有限元方法研究燃氣輪機帶冠葉片振動特性的分析模型和計算方法.算例和工程應用證明了該方法是效性的、正確的,並可以大大降低計算分析規模.研究表明帶冠葉片動力特性分析時必須考慮整圈葉片的耦合效應
  4. The optical waveguide characteristics such as waveguide mode field profile, and the mode cut - off conditions, and the waveguide dispersion are analyzed with the solution of a certain wave equation. the mechanism of index ellipsoid of linbo _ 3 crystal distorted with an external applied electric field by means of the electro - optic tensor as investigated. based on the operation principle of m - z waveguide, the operation mechanism of the two - section cascaded m - z waveguide and of the modulation electrode are

    調制器的結構設計從m - z干涉型光波導工作原理出發,分析兩級串聯m - z干涉型光波導的工作原理,調制電極的工作原理,從而設計出了工作於1 . 054 m的、兩級串聯m - z干涉型光波導、行波電極linbo _ 3為強度調制器的結構參數。
  5. The lineshape analysis of electric field modulation spectroscopy of semiconductor quantum dots

    半導體量子點電調制吸收譜一次微分性質的理論分析
  6. In this field, swing modulation by the polarize device were designed, this method was the base of our spatial light modulator

    在這一方面的探索中,人們創立了通過偏振器件完成振幅調制的方法,這種方法是本空間光調制器的基礎。
  7. This paper expatiated that the mathematics models of ac motor is higher order, non - linear and closed coupling, multivariable input - output system. and introduces the principle and the algorithm of sine pulse width modulation ( spwm ), opened - loop space voltage pulse width modulation control ( svpwm ) and field oriented control ( foc ). finally, realized the control strategies of variable - frequency speed regulating using assembly and c language

    文中闡述了交流異步電機的數學模型是高階、非線性、強耦合的多變量輸入輸出系統,介紹了交流電機的正弦脈寬調制、開環電壓空間矢量的u / f控制和磁場定向控制的原理及控制演算法,並利用dsp構成控制系統,通過匯編語言和16位定點c語言混合編程的方法實現了上述的變頻調速控制策略。
  8. The pseudo - random fsk / psk multi - modulation signal and the partly - matched processing signal remain the information of the target of interest. compared with the other processing methods, the partly - matched procession could depict the target ' s information effectively, and could get a higher output snr under a noisy environment. in this dissertation, the deduction and the simulink on the computer of the average ambiguity function of the pseudo - random fsk / psk multi - modulation signal are presented. also, to the partly - matched procession, analysis in theory and simulink on computer are presented. the partly - matched procession applied in radar field is also discussed

    較其它處理方法,非完全匹配處理能有效的突出所觀測目標的信息,以及在加噪情況下,其具有高的輸出信噪比。在論文中,對偽隨機fsk / psk復合調制信號的模糊特性進行了推導與模擬,對非完全匹配處理方法進行了理論上的分析以及計算機上的模擬驗證,討論了其在雷達中的應用。
  9. The principle advantages of vcsels over conventional edge - emitting lasers lie in ultralow threshold current, small far - field divergent angle, high modulation frequency, potential for wafer level testing and the ease for single longitudinal mode operation and two - dimension integration. as a result they show considerable promise for applications such as optical fiber communication, parallel optical interconnects, optical information processing and neural networks, etc. a direct coupling theoretical model in quasi - three - dimension for the gain - wave guide vertical - cavity surface - emitting lasers has been created in this paper

    它與傳統的邊發射激光器相比具有更優越的特性,例如,具有極低的閾值、較小的遠場發散角、調制頻率高、易實現單縱模工作和二維集成,無須解理封裝即可進行在片測試等,所以,它被廣泛應用於光纖通訊、并行光互聯、光信息處理、光神經網路等領域。
  10. High resolution digital smps becomes the hotspot in the power supply field. more and more attention has beed payed to how to realize high resolution digital smps, and it has already taken a long step develop. improving the resolution of digital smps by new techniques becomes a forever topic. under the learning of the status and develping trend of smps, considering the practical requirement of task, a control system of smps implemented by microcontroller with high resolution, high speed, high integration is carried out. by combining the embedded system and power electronics, it is discussed that a high resolution smps ’ s output voltage with 0. 01 % resolution pwm wave output, in the basis of microcontroller, and the pwm wave double modulation arithmetic

    不斷用新技術手段實現數字開關電源的高精度是一個永恆的話題。經過了解國內外開關電源的發展現狀和發展趨勢,結合實際課題的要求,提出了使用高精度、高速度、高集成度的微控制器組成開關電源的控制系統。討論了將嵌入式系統與電力電子結合,在微控制器硬體基礎上通過軟體pwm波雙調制演算法輸出高精度pwm波,實現開關電源輸出電壓的萬分之一精度的方法。
  11. Adopting rotor field - oriented vector control methods, through which make the stator and the rotor magnetmotive forces can be kept orthogonal all along during operation of the bldcm, combining hysteresis current modulation ' s current control advantage and space voltage vector modulation ' s torque ripple attenuation advantage, then designing a sort of bldcm hysteresis current svpwm control method

    摘要研究採用轉子磁場定向的矢量控制方法使無刷直流電動機定、轉子磁勢矢量始終保持正交,結合滯環調制電流控制和空間電壓矢量調制,設計了無刷直流電動機滯環電流svpwm控制方案。
  12. In 1980 ' s, a new economic field - eco - economics - births. it provides the direction of society developments the ecosystem economics thinks the economic system is the second stage system of ecosystem or sub - system of environment, emphasizing mankind social economic activities have to obey natural ecosystem regulation, limiting economic scale in the resources supply of ecosystem system and the ability of wastes modulation

    生態經濟觀認為經濟系統是生態系統或環境的亞系統或子系統( sub - system ) ,強調人類社會經濟活動必須服從自然生態規律,將經濟規模限制在生態系統的資源供給和廢棄物調節能力之內,以維護生態系統結構和功能的穩定性,從而保證人類社會的生命支持基礎和社會經濟的可持續發展。
  13. In this paper, we analyzed the modulation of the interference intensity of each pixel on the time sequence speckle patterns in the time domain and proposed a new phase retrieve method, time sequence phase method ( tspm ), in which the time sequence speckle interferograms are used to obtain the whole field deformation of the object

    本論文通過對序列散斑圖上各點在時間軸上散斑強度調制函數的變化進行分析,提出了一種基於時間序列的散斑干涉場的相位解調方法,進而獲得物體全場變形信息。
  14. In this paper, a novelty space vector pulse width modulation ( svpwm ) technique for the two - phase inverter - fed asynchronous motors system is proposed, which can be widely employed in the low or middle power level field

    本文研究了兩相逆變器-異步電動機系統的svpwm控制技術,該系統可以廣泛應用於小功率、寬調速運行的場合。
  15. The modulation recognition of communication signals is one of the key techniques of communication reconnaissance, and it is also an important task in the field of electronic warfare

    通信信號調制方式的識別是通信偵察的關鍵技術之一,是目前電子戰的重要研究課題。
  16. This paper applies the technology of frequency agility to radio fuze which has been applied widely in the field of radaf and communication, and introduces a scheme of frequency agility and frequency modulation fixed - distance fuze which has good precision of fixed - distance and strong ability of anti - interference

    本文將應用於雷達和通信領域的頻率捷變技術引入到無線電引信,提出了一種既具有較高定距精度,又具有較強抗干擾性能的新的頻率捷變調頻定距引信方案。
  17. In this dissertation, ofdm which has been the hottest spot in communication field recently will be considered as my direction. the dissertation will study some key techniques in mc - cdma system, such as modulation technique, peak - average power ratio, detection technique and synchronization problem of the whole system. what ' s more, the results of calculation and simulation will be given

    本文以目前通信領域的熱點: ofdm (正交頻分復用)為研究方向,對于多載波cdma系統中的若干關鍵技術,即多載波cdma系統中的調制技術、峰平比性能、接收端檢測技術以及整個系統同步問題進行了研究,並給出相應的計算機模擬結果。
  18. Besides, the motor control system based on the digital signal processor ( dsp ) is analyzed. the hardware circuit about the dsp system is designed. the dsp control software is programmed on the field magnetic orientated control and the space vector pulse width modulation ( svpwm ), that establishes the ' basis for implementing the modern control principle

    然後,又對基於數字信號處理器( dsp )的電機控制系統進行了分析,設計了dsp系統的硬體電路,並編寫和調試了空間磁場定向控制和空間矢量脈寬調制( svpwm )的dsp系統的軟體,為直線電機現代控制策略的具體實現奠定了基礎,並提出了對端部效應進行補償的控制方法。
  19. Based on the mathematical model of induction motor, this paper discusses the rotor - field - orientated control principium and the space vector pulse width modulation principle. subsequently the software design of svpwm is put forward

    本文在分析感應電機數學模型的基礎上,詳細討論了轉子磁場定向矢量控制理論和空間矢量脈寬調制技術原理,提出了svpwm的軟體實現方法。
  20. In the first stage, due to the research in years on the magnetic field modulation type doubly fed brushless machine, two doubly fed generators was requested to fabricate

    首先,利用我們研究所在磁場調制式無刷雙饋電機的多年研究成果,研製並測試兩臺無刷雙饋發電機。
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