最小信號 的英文怎麼說
中文拼音 [zuìxiǎoxìnháo]
最小信號
英文
minimum signal-
Mems ( micro electromechanical system ) has become one of the most rapidly development technologies. along with the rapid development of mems techniques, capacitive sensor is used widely whose capacitance changes small, which has put forward the new request to the measurement technique. the common measure for capacitance measurement is that convert capacitance to voltage, electric current or frequency. the area of polar plate of the capacitor becomes smaller and smaller, and the total capacitance of micro capacitive sensor is usually several pico farad only. as a result, its change amount is smaller
Mems （ microelectromechanicalsystem ）近年來發展最快的技術之一，隨著mems技術的快速發展，電容式加速度計的電容變化變化量越來越小，對檢測技術提出了新的要求。在電容式傳感器中，常用電容檢測電路是將其轉換為電壓、電流或者頻率信號。目前的微型電容傳感器的極板面積變得越來越小，電容總量只有幾個pf ，變化量就更小。Letter ratio : point biggest not lose the signal strength of the true voice with at the same time of the emanative noise strength opposite voice for of ratio, usually with meaning, letter comparing more bigly, turn on electricitying the road more small, quality more pure and unadulterated. want to choose the letter the ratio in the product of above. new of summer is with the series the product s letter ratio all in the above, have more professional of performance
信噪比：指最大不失真聲音的信號強度與同時發出的噪音強度之間的比率，通常以表示，信噪比越大，功放電路的相對噪聲就越小，音質就越純正。要選信噪比在以上的產品。夏新和系列產品的信噪比都在以上，有更加專業的表現。Four tem - horn antennas have been made. using these antennas two - element rain gutter tem - horn array, two - element stacked tem - horn array, four - element rain gutter tem - horn array and four - element stacked tem - horn array are been mades up of. the results of experiment accord with theory and numerical stimulation
最後，對tem喇叭天線陣列進行了原理性實驗研究，設計了帶地板結構的半tem喇叭天線，組成二元槽狀陣列、二元疊狀陣列、四元槽狀陣列、四元疊狀陣列等，應用小信號測試，得到的結果與理論和數值模擬相一致。Compared to the traditional converter, the new one can transform electric power from a static part to a rotary part without an electrocircuit connection, which makes the contactless power transform come true. one application of this converter is to supply a steady and regulable excitation circuit for synchronous generator by integrated its second winding with the motor while its primary winding is static. the thesis gives two methods of the rotating converter design paticullarly : flyback and fullbridge, and explains how the circuits are designed
通過理論分析、模擬分析和實驗驗證，得出這兩種旋轉變換器都能進行感應電能傳輸，但它們的傳輸功率是不同的，反激式旋轉換器最大隻能傳輸幾十瓦功率的感應電能，因此只能用在感應電能傳輸較小的場合，或者信號傳輸的場合;而全橋式旋轉變換器能傳輸較大的功率，可用於電機的新型無刷勵磁方案中。Based on the theories described above, calculation formula of general dimension of least square measure and multi - fractal fault diagnosis and analysis system have been established with borland c + + builder 5. 0, and checked by pure sinusoidal and cosine signal and sinusoidal signal with noise, and verified by the examples
基於上述原理，建立了最小二乘法的廣義維數計算公式，用borlandc + + builder5 . 0編制了以廣義維數計算分析為基礎的多重分形故障診斷系統，並對標準的正弦信號、餘弦信號及帶有噪聲的正弦信號進行了驗證。We select ni / cr alloy resistor as element together with ceramic embedding hearth ; select small flat - and - disc heat - even hubby ceramic sample holder, select ni / cr & ni / si thermoelectric couple ( type k ) as thermoscope with threads 0. 5 mm in diameter which is installed in the middle of the holders symmetrically ; select aluminum silicate fire - retardant fiber as materials for heat preservation ; design some hardware, for example temperature controller & transporter, signal amplifier etc ; design controlling curve to heat stove ; and introduce the method of least squares nonlinear regression and subsection function to deal with data. in order to obtain the reasonable operation conditions and operation curve, we have also done many theory analysis and experiment discussions
通過理論和試驗探討，選用鎳鉻合金電阻絲作為加熱元件，配以陶瓷質埋入式爐膛；選用陶瓷質小尺寸扁平?圓盤均熱塊體型樣品支持器；選用0 . 5mm絲徑鎳鉻?鎳硅熱電偶（ k ）作為測溫元件；熱電偶對稱安置在樣品支持器容器的中部；選用硅酸鋁耐火纖維作保溫材料；合理選用和設計了溫度控制器、溫度變送器、信號放大電路等硬體；採用升溫曲線來控制爐膛供熱過程；採用最小二乘法非線性回歸與分段函數相結合的曲線模擬方法，進行圖形處理。First, the nonlinear ls problem without constraint is converted to that subjected to inequality constraints by putting constraints on the do as of the received signals and toas of the first arrived signal with geometrically based single - bounce ( gbsb ) statistical channel model and cost - 207 model. then, a penalty function is used in the estimation of ms position
首先，用基於幾何結構的單次反射圓模型和cost - 207模型，對期望定位用戶的各條多徑信號的波達方向和最先到達多徑信號的時間進行約束，將傳統的解無約束的非線性最小二乘定位問題或近似線性最小二乘定位問題轉化為解不等式約束的非線性最小二乘定位問題；然後，用內點罰函數法估計移動臺的位置。Main conclusions drawn from the analyses of calculating results are as follows : ( 1 ) the microwave absorption of atmosphere gas have obvious attenuation at the wavelengths for cloud detection, thereinto, the water attenuation effect changes greatly, so the 94ghz cloud detecting radar should have water vapor attenuation correction scheme. ( 2 ) when 37ghz and 94ghz radars detect clouds, the difference between the atmosphere and cloud attenuation and the large variety of radar reflectivity conduce the intension of the radar backscatter signals change. ( 3 ) for the thin cloud layer and low water content of cloud, 37 - ghz radar backscatter signals are not as good as 94 - ghz radar, that is to say that the 94ghz radar has better capability in thin clouds detection
本工作得出如下結論： （ 1 ）大氣氣體的微波吸收在測雲波段產生明顯的衰減，其中水汽衰減效應變化很大；即將上天的空間94ghz測雲雷達必須有水汽衰減訂正方案； （ 2 ） 37ghz和94ghz雷達測雲，由於大氣和雲衰減不同和雷達反射率的很大差異，導致雷達回波信號強弱不同； （ 3 ）對雲層較薄、含水量較少的雲，在不計雷達參數的情況下， 37ghz雷達回波信號不如94ghz測雲雷達，也就是說94ghz對薄雲有更強的探測能力；對雲層較厚、含水量大的雲，由於強衰減的作用， 94ghz雷達回波信號小於37ghz雷達； （ 4 ）從大氣衰減的不利因素方面考慮，空間94ghz雷達測高層薄雲的效果最好；測低層薄雲時需要考慮氣體衰減訂正；因濃厚雲的強衰減作用，探測其中下部的能力大大減弱，不僅要進行衰減訂正，而且要藉助其他信息來反演整個雲層的含水量垂直分佈； （ 5 ）為了獲得從極薄到極濃厚雲的垂直分佈探測能力，未來測雲雷達系統最好採用雙波長甚至三波長（如94 、 37和13ghz ） 。The bias magnetic field of the bias coil driven by bias current and small signal test current, results in the induced signal of the control coil. the terminal voltage of the control coil is detected by the test circuit. then the signal containing the information of rotor displacement is obtained, from which we can get the dc voltage signal proportional to the rotor displacement through half - wave rectification circuit and low pass circuit. this dc signal is put into a pid controller to get the control signal of the rotor displacement
偏置測試電路向偏置線圈輸入偏置電流和小信號測試電流，兩者產生的偏置磁場在控制線圈產生感應信號，檢測電路檢測控制線圈端電壓並提取含有轉子位移信息的電壓信號，該信號經半波整流電路和低通濾波電路后得到與轉子位移成正比例的直流信號，再由pid控制器轉換為轉子位移的控制信號，最後控制信號輸入功放電路產生控制電流，實現閉環控制。The methods of direction finding mainly include maximum ( minimum ) signal method, amplitude - comparison method, phase - comparison method and time difference method
測向的方法主要有最大（最小）信號法、比幅法、比相法、時差法。This paper mainly describes the small signal model and properties of the dc / dc converter, the optimum control model of the dc / ac inverter and analyses the stability and dynamic characteristics of the system. the experimental results show that the static inverter achieves high performance target
本文主要對6kva電源變換器系統進行了分析，包括前級dc dc變換器的小信號特性，后級dc ac逆變器的最優控制模型，分析了系統的穩定性和動態性能，模擬和實驗表明該電源變換器具有高的性能指標。Theoretically several solutions are derived in the final scheme such as broadband matching technology which included negative - feedback technology, traveling wave technology and balance technology. in addition, the design will be optimized by eda software and the final test result indicates that our design is successful. the principle of microwave amplifier is introduced at first in this paper, especially its main parameters index sign, then the material performance and the influence of parasic parameter and model setting of the gaas phemt is discussed
文中首先介紹寬頻帶放大器的主要參數指標，接著介紹了gaasfet的材料特性，以及phemt管芯寄生參數對實際放大器設計的影響，然後討論gaasphemt的大、小信號模型的建立與分類;結合gaasphemt模型和s埠參數分析了寬頻帶匹配技術的原理;最後論述本課題中各個放大器實現的具體方案，以及在放大器實現過程中應該注意的問題，給出了實際寬帶放大器的測試結果，並將軟體模擬結果與實測曲線進行對比。The time base drift deduced by the change of temperature is discussed particularly and the compensation method of it is analyzed. finally, we also studied frequency band extension under time base distortion condition by simulation. the results show that the compensation of time base distortion can reduce the error of signal and then increase the accuracy of frequency band extension
首先，介紹時基失真的相關概念及其對測量信號的影響；其次，對時基失真特性測量的不同方法進行了理論分析和比較，並對分析信號法進行了模擬研究；再次，對時基失真的補償方法進行分析和模擬研究；並專門對溫度變化引起的時基漂移及其補償方法進行了簡要分析；最後，對時基失真條件下的頻帶展寬技術的模擬表明時基失真的補償可以減小信號的誤差，因而提高頻帶展寬的精度。Finally, the influence the radius of the electron beam, current of the electron beam, the acceleration voltage and the geometrical dimension of the slow - wave structure on small signal gain are discussed
研究表明：對應最大的增益，有一飽和電壓存在；小信號增益隨電子注電流的增大而增大；也隨電子注半徑的增加而增大。In the first chapter, the study background. direction and main content of this paper are presented. in the second chapter, the character and application of motorola dsp chip, the system design of this power supply and a small - signal model of fbps converter are introduced. in the third chapter, the operation of fbps converter is analyzed in detail and the design of hardware is given. in the fourth chapter particular software design and program flow are given. the result and analyse of experiment are given in this chapter too. in the last chapter, summarize of full paper and works followed are given
本文第一章介紹了課題的研究背景、方向和主要內容；第二章簡單闡述了dsp晶元的特點及其在電力電子領域的應用，介紹了motoroladsp晶元dsp56f8323的性能特點；提出基於motoroladsp控制的移相全橋軟開關dc dc變換器的硬軟體系統設計方案；最後建立移相全橋變換器的小信號模型進行系統分析。第三章分析了系統硬體部分即軟開關全橋變換器的工作原理和工作模式；給出了詳細的硬體設計。Their input and output lines should be decoupled at all frequencies, they should be shielded to prevent external electric and magnetic fields from causing interference, and they should be sited as far as possible from sensitive circuits so that residual electric and magnetic fields are prevented by distance from doing serious damage
開關電源的輸入輸出線必須進行全頻段去耦處理；要藉助屏蔽手段抑制電、磁干擾；開關電源要盡可能遠離小信號電路，確保其電磁場對模擬電路影響最低。One of the key techniques is the detection of near infrared ( 1310nm and 1550nm ). because the quantum key is transmitted by one photon, and 1310nm and 1550nm infrared are the lost loss wavelength in fiber. we can detect the visible light now, but it is difficult to detect the near infrared because of its low energy
量子通信的關鍵技術之一就是紅外（ 1310nm 、 1550nm ）單光子探測，這是因為光量子密鑰傳輸是採用單個光子來實現的， 1 . 3微米和1 . 5微米是現在所使用的光纖通信中損耗最小的波長，現有成熟的單光子探測器工作波長都是在可見光波段，而紅外光子因為能量小，信號非常微弱，極易被噪聲淹沒，因而非常難探測到。Secondly, basing on the theory of on - off gain of small signal, the raman gain coefficient for frequency shift between 0. 5 and 20 thz of standard sigle mode optical fiber is measured by pump - probe method through a super luminescent diode ( sld ) as a broadband small signal probe source. thirdly, numerical simulation analysis of gain characteristic of raman fiber amplifier for c band wdm signal light is made according to the raman gain coefficient of the fiber measured before through target and four rank runge - kutta method. at the invariability of wavelength and maximum power of each of two pumps, schematic of powers of two pumps for best flatness on c band wdm optical gain was found out, at the same time, the factors of resulting in gain saturation is analyzed, too
本文首先應用經典的電磁理論對拉曼光纖放大器的工作機制進行了分析，然後，根據小信號理論推導出的開關增益求出了光纖拉曼增益系數的表達式，採用泵浦-探測波的方法，利用超輻射激光二極體（ superluminescentdiode簡稱sld ）作為探測光源，測量了所用標準單模光纖頻移為0 . 5 - 20thz的拉曼增益系數，之後根據所測得的光纖的拉曼增益系數譜對應用該類光纖構成的放大c波段wdm光信號的拉曼光纖放大器的增益特性採用打靶法和四階龍格- - -庫塔進行了數值計算，在給定了兩個泵浦光源的波長和最大功率后，找出了反向泵浦情況下使c波段wdm光源增益最平坦的兩個泵浦的各自最佳功率，同時也分析了導致信號光飽和的原因。At light loads, the architecture allows the chip to “ skip ” cycles to reduce power dissipation. in the circuit design, the basic principle and small signal model of the boost power stage are given at first, and then the stability and small signal model of the control loop are also analyzed, finally, the whole chip architecture and sub - block parameters are presented according to the application requirements
在電路設計中，首先闡述了升壓型直流轉換器的功率輸出級的拓撲結構、基本原理、小信號模型，然後分析了電流模式控制迴路的穩定性及小信號模型，最後根據應用要求進行了電路的總體架構設計，完成了每個子電路的各種參數的分析、計算。Then small signal model for sepic - pfc converter as well as its control scheme is developed and used to optimize regulator ' s parameters. time domain simulations in detail of the converter are carried out and physical and mathematical explanations are given for the results of simulations
然後研究了sepic - pfc變換器的小信號模型並建立了系統的控制模型，根據控制模型對控制參數進行了優化設計。最後對系統進行了深入的時域模擬研究並給出了模擬結果的物理和數學解釋。分享友人