時基調制 的英文怎麼說
中文拼音 [shíjīdiàozhì]
時基調制
英文
time base modulation-
In this thesis, firstly, we put forward a new algorithm of the synchronization of carrier reference phase, that is to use the curve synthesizing with the general digital carrier phase looper to have an estimation on carrier frequency within 10 ms so as to meet the need of meteor burst communication. we have done some simulations to get the performance of carrier frequency estimation using two modulation modes ( 16qam and 4 - qpsk ), and had some test on the carrier phase looper in conditions when using different baud rate transmission and when the baud tuning have windage
我們對兩種正交調制方式（ 16qam和4 - qpsk ）進行了模擬工作並給出了模擬結果，同時討論了碼元同步定時誤差對鎖相環路工作的影響並根據流星通信中使用變速率傳輸時鎖相環路的載波同步性能進行了測試；然後在基於軟體無線電思想的數字處理平臺（該數字處理平臺實現了中頻數字化）上用dsp軟體完成了載波的相位跟蹤。Compared with non - passerine, they appeared longer syllable length, higher basic frequency and more viable frequency ranges. though the amplitude modulation properties enhanced their vocal production, the type of syllable is still stable and less of variety. so the phrase consisted of syllables are comparatively few and changes of the tone are relatively less
且表現出很強的頻率調制特性和特有的幅度調制特性，相對的音節時程比較長，基頻較高且頻率變化范圍較大，所特有的幅度調制特性更增加了其控聲的能力，但其音節的種類仍很單一，缺乏變化，由音節所組成的句型較少，音調變化幅度不大，因此，其叫聲質量盡管較非鳴禽有所改善，但相對鳴禽而言卻又遠遠不如。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。Space - time trellis coding for uwb systems based on different modulations
基於多種調制方式的超寬帶空時網格編碼In attempt to directly compare the sound response characters of the same bf neurons or different bf neurons and their interactive relation, the double recording microelectrodes were penetrated into two different neurons in iso - frequnency laminas or hetero - frequency laminas. taking advantage of frequency tonotopical arrangement in 1c of bats, it was explored how the neurons integrated different parallel processes of the same sound information. in the case of which, we hoped to explore the relation between the sound response characters of the central auditory neurons and neural modulation in background noise for the further understanding of the mechanism in the central auditory neurons extracting sound signals
本研究以大棕蝠（ bigbrownbat ， eptesicusfuscus ）為模型，利用ic聲調組構排列成同頻層這一結構特點，突破單電極記錄和檢測神經元的方法，同時推進兩單電極至一個同頻層或兩個同頻層的兩個不同神經元，試圖從細胞水平直接比較兩個具有相同和不同最佳頻率的神經元聲信號的加工處理特徵、以及它們之間的相互關系，以期窺探它們在對同一聲信號處理過程中的整合奧秘，並以此為基礎分析和探討背景噪聲條件下中樞神經元聲反應特徵與神經調制的關系，以期進一步了解中樞聽神經元聲信號提取的機制。When the cur - cuit resets, the chip remains accepting state, works in burst mode, and adopts dpsk modulation mode. it proceeds quadrature - sampled intermediate frequency signal after the ad9057 has converted, then down - converses, despreads and demodulates. the demodulated baseband signal will be sended into scm to dispose through interrupt
上電復位后，晶元處于接收狀態，工作在突發模式下，採用dpsk調制方式，將ad9057轉換完的中頻信號進行復正交取樣後下變頻、解擴、解調，通過中斷將解調完的基帶信號送入單片機處理；處于發送狀態時，可將數據擴頻、調制，經ad9768送出。First, how to conduct sample and quantification of continuous time signal which is prior condition of sdr is explored in detail, and the comparison and analysis of some sample modes are given in which band pass signal sampling theorem is most important. second, multi - sample rate signal processing which is an important basis of sdr is studied. emphasis are put on decimation and interpolation those are the most fundamental process and the realization of decimation and interpolation filter
在基於中頻采樣的軟體無線電結構框架下，首先詳細探討了軟體無線電的前提條件，即如何對連續時間信號進行采樣量化，比較分析了幾種采樣的方式，其中最為重要的是帶通信號采樣定理；然後探討了軟體無線電的一個重要基礎，即多采樣率信號處理，重點討論其最基本的兩個過程抽取和內插以及抽取器和內插器的實現；接著介紹了結構簡單、適用於一級抽取的cic濾波器和適用於做2倍抽取的半帶濾波器；再次論文在總結了傳統的調制解調基礎上，結合軟體無線電器件的特點，系統的探討並實現了基於正交思想的am 、 fm 、 ask 、 fsk 、 bpsk 、 qpsk的正交調制解調演算法。The subject inducts digital time division technology ( pwm ), which is more advantageous at the accuracy and the predigest of hardware than simulant multiplication. what they call measuring power energy reasonably is that measuting except harmonics power energy fed back power. yet it realizes reasonable measurement of power energy which measures by base wave ac parameters method base on digital time division
本課題引入了數字時分割（ pwm ）脈寬調制技術，在測量的準確性、硬體電路的簡化等方面都比模擬乘法器具有較高的優越性。所謂合理的計量電能，就是不計非線性負載回饋給電網的負的諧波電能，而採用基於數字時分割的基波交流參數測量的方法，真正實現了電能的合理計量。This paper mainly focuses on the noise limiting by means of the direct sequence spread spectrum ( dsss ) and the analysis of the transmission performance of the plc and some digital modulation technology. the contents of the paper is as follows : 1 ) the technical feasibility is proved after simulating noise limiting principle of dsss by means of systemview, the simulation software ; 2 ) a kind of band pass filter ( bpf ) is realized according to the requirement of filter and the principle of butterworth approximation, which satisfies the index of performance of dsss. 3 ) the low voltage plc system includes the sc1128, the specific modulation / demodulation ic, the bpf filter and other circuit components, furthermore, the control function of system is realized by means of the personal computer and the microcontroller
本課題在對低壓電力線的傳輸特性和數字調制技術進行分析的基礎上，將通信理論中的直接序列擴頻技術（ dsss ）用於解決低壓電力線通信的干擾問題，主要研究內容如下： （ 1 ）用通信模擬軟體systemview對dsss技術的通信和抗干擾原理進行模擬分析，分別對時域和頻域下採用dsss技術前後接收信號的頻譜進行分析，驗證dsss技術在本系統中的可行性； （ 2 ）由dsss技術對濾波系統的要求，根據濾波理論分析了巴特沃思型濾波器的逼近原理並設計了合適的濾波電路； （ 3 ）用調制解調晶元sc1128和自行設計的濾波器加之輔助外圍電路，構造出低壓電力線載波通信系統，並採用atmel公司的單片機設計了接收和發射電路的微控制器； （ 4 ）分別對採取抗干擾措施前後輸入和輸出信號進行對比實驗，並對結果進行分析，驗證了dsss技術對干擾信號的抑制作用。During the circuit design, the author analyzed the basic principle of the direct current motor, pwm control, h - bridge power driver, and two control techniques of h - bridge power drive circuit, designed its general structure, so the feasibility of the design is confirmed. then, reference, oscillator, power dmos gate drive circuit ( charge pump, bootstrap ), and dead time generation circuit are designed and analyzed in the sub - circuits. a current - controlled oscillator is presented in this thesis
在電路設計中，作者介紹了直流電機的工作原理和數學模型、脈寬調制（ pwm ）控制原理、 h橋電路基本原理和h橋功率驅動電路的兩種控制模式，設計了驅動電路的總體結構，給出了電路的功能模塊，確定了設計的可行性，然後在子電路模塊中，重點分析設計了基準源電路、振蕩器電路、高端功率管柵驅動電路（電荷泵及自舉電路） 、低端功率管柵驅動電路和死區時間產生電路。This dissertation is the expanding of the military project of ‘ 95 ’ advance research, a novel multi - modulation technique designing radar signal waveform is introduced on the links with the project of the national natural science fundation of china ( nsfc ), named " produce and process the multi - modulation signal of the sensor with strong detectability and identifiability ". based on the analysis of the equal - probability - distributing fsk / psk multi - modulation signal, we construct a new pseudo - random fsk / psk multi - modulation signal and we design and simulink on the computer the partly - matched processing signal of this signal. the purpose of the design is to construct a processing signal to combine with the pseudo - random fsk / psk multi - modulation signal, so that we could get a strong response of the target
本論文是『九五』軍事預研項目「低截獲概率雷達波形研究」的擴展與深入，同時結合國家自然科學基金項目「強探測強識別傳感器新型復合調制信號產生及處理」展開。在分析等概率分佈的fsk / psk復合調制信號的基礎上，構造了一種新的偽隨機fsk / psk復合調制信號及其非完全匹配處理的設計及模擬。設計的目的是能對偽隨機fsk / psk復合調制信號進行處理的處理信號，以期獲得對所探測目標信息的強探測。And some experts even believe, the trend in the development of the iax system was, for quite some time, towards keeping high statutory tax rates, but simultaneously provide generous tax incentives tha t reduced the tax base. the basic asymmetry of tax system may favor large concerns, which may be in a better position to take advantage of the provisions in the tax code in certain states of nature. the result may be lower expected average and marginal tax rates, and a lower cost of capital, compared to newer and smaller companies
更有學者認為，在以往很長一段時間里，稅制的發展趨勢是高法定稅率，同時附加大量稅收激勵來縮小稅基，稅制的這種基本不對稱性對大公司有利，可以面對低預計平均和邊際稅率以及低資本成本，然而大公司基於其擴張性的組織結構，與富有彈性的內容提要小公司相比，它轉變供求狀況的適應能力相對遲緩，那麼偏祖于大公司的稅收政策可能會阻礙宏觀經濟增長率和結構調整。This thesis analyzed the error performance of mfsk and mpsk modulator in hf with optimal receiver, studied the shortcoming and strongpoint of several typical short - wave data transmission systems and their performance over fading and intersymbol interference channels. the theory and key technical of adaptive modem is discussed. in the last, an efficient modulation scheme - block coded modulation is introduced into hf radio systems to improve the efficiency of hf data transmission, this paper also proposes a hf data transmission system scheme composed of a block coded modulator and a decision feedback type adaptive equalizer
本文在對短波數傳兩種常見調制方式fsk及psk最佳解調性能分析的基礎上，討論了幾種採用典型調制技術的短波數傳系統（如時頻調制、多進制頻移鍵控慢跳頻、 chess系統）原理、優缺點以及抗衰落和抗符號間干擾的性能；分析了自適應串列數傳系統抗短波通道衰落和多徑干擾的原理、關鍵技術；在本文的最後引入一種有望解決短波數傳系統低效率狀況的調制方式bcm -分組編碼調制，給出了一個採用bcm技術與自適應均衡技術相結合的短波數傳系統方案，並通過計算機模擬進行了初部驗證。Based on the output - voltage error function, a novel time discrete modulation technique is proposed for matrix converters ( mcs ) and time - discrete difference equations of a mc circuit are derived
摘要針對矩陣變換器調制方式的特點，提出了基於輸出電壓誤差函數分析的矩陣變換器離散調制技術，推導了基於時間離散和差分原理的電路方程。The system is based on a ' subaudible ' tone injected after the audio stages into the transmitter during encode and the tone is detected before the audio circuits in the receiver
這套技術的基本原理如下，進行編碼（調制）的時候，一個「亞音」音頻信號被注入聲音信號，並在接收端的音頻電路前檢測這個音頻信號解碼。Secondly, introduce discrete multi - tone modulation principle in detail, have a systemic and comprehensive analysis and explanation on minimum mean square error ( mmse ) channel shorten time domain equalizer design methods which are based on all kinds of cost functions, analyze their advantage and disadvantage. research on time domain equalizer structure, compare all the time domain equalization algorithm with simulation which afford a valuable reference for the choice of equalization algorithm and equalizer structure when design time domain equalizer
詳細介紹離散多音頻調制原理，對mmse通道縮短法和基於其他代價函數的時域均衡器設計方法的進行了系統全面的分析和闡述，分析了各自的優缺點；對時域均衡器結構進行研究；模擬比較了各種時域均衡方法，為進行時域均衡器設計時均衡演算法、均衡器結構的選擇提供了有價值的參考。On the basis of testing on operation parameter of power machinery, carry on dynamic real - time control automatic adjustments to the equipment, to ensure that equipment is safe, reliable and efficient operation
在對動力機械運行參數檢測的基礎上，對設備進行動態時實控制、自動調節，保證設備安全、可靠、高效運行。3 using current injecting frequency modulation method and modulating sine wave around the resonator point, the lock - in phenomena is observed in a comparatively short period of time. this has achieved the basic goal for a closed loop r - fog
3 、採用電流注入法，在諧振點附近進行正弦調制，實現了對諧振點的短時間鎖定，達到了閉環光纖陀螺設計的首要基本要求。Based on the investigation with several voltage control methods, such as venturini method, instantaneous double - voltage synthesis method and space vector modulation method ( svm ), three new control strategies are put forward. firstly, a time - varying modulation coefficient svm method is proposed to improve mc ' s anti - disturbance performance under the asymmetry input voltage. secondly, a 5 - state switching strategy is presented for mc controlled by the svm method, which reduces the commutation number and switching losses remarkably
在分析了venturini控製法、瞬時雙電壓法、空間矢量法等電壓控制方法的基礎上，提出了在非對稱輸入條件下矩陣變換器空間矢量法的時變調制比改進控制策略，提高了變換器的抗干擾性能；對空間矢量法的開關策略進行了研究，提出了新型5狀態開關策略，在保證其他性能不受影響的條件下，減少了變換器的換流次數和開關損耗；提出了一種矩陣變換器單電壓合成的新方法，它不僅使得變換器的控制簡單，計算量減少，而且使得開關損耗達到最少。This dissertation focuses on the hardware design of software radio with the aim to solve the problem of producing and receiving space - time modulation signals
本文就基於pci總線的軟體無線電硬體實現開展了初步的研究，目的是用來解決中頻時空調制信號的產生與接收問題。分享友人