調制頻帶 的英文怎麼說
中文拼音 [diàozhìbīndài]
調制頻帶
英文
modulation band-
In this paper, research on the algorithm of complete digital if and baseband transmission system and the realization of transmitter and receiver. / 4 - dqpsk is chosen as digital modulation scheme. the scheme of demodulation is baseband differential detection. sliding correlator can realize the symbol synchronous acquisition ; early - late gate synchronizer is used to do symbol synchronous tracking
系統的發射機選定/ 4 - dqpsk為調制方式，接收機採用基帶差分解調的非相干解調方式，滑動相關器捕獲發送的pn序列，早遲門同步器跟蹤符號同步，使用相關器對同步后的符號進行最佳判決，並在這些演算法實現的基礎上，實現了直接序列擴頻和解擴技術。With the established rf front - end system simulation platform, adding the digital modulated baseband signal, this paper simulated the multifold digital modulated signal ’ s transmission, such as 2ask, qpsk, and 16qam. then researches of power compression and phase noise of local oscillation influence the bit error ratio for different modulated system. the designing is satisfied multifold functions request with the high - powered and integrated broadband rf front - end
隨后在建立的寬帶射頻前端通用模擬平臺上，加入基帶數字調制信號，對多種數字調制格式的信號在該通用平臺上的傳輸作了研究，模擬了2ask 、 qpsk和16qam等調制格式信號的發射與接收，研究了功率壓縮和本振相位噪聲對不同調制的誤碼率影響，實現了滿足多種功能要求的寬帶高性能綜合射頻前端的設計。When there is a modulated signal from transmitter, there are side bands.
只要在發射機中存在調制信號，就含有旁頻帶出現。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。A novel pwm dc converter with snubber cell
一種新的帶有緩沖單元的脈寬調制式直流變頻電路Telegraphy using frequency modulationnarrow band direct printing
頻率調制發射窄帶印字系統The catv charge and control system is mainly composed of the management software 、 the header data modulator and the terminal charge and control equipment. i am responsible for design catv charge and control equipment and test system. the header data modulator is used to encrypt the control single from computer and transmit it into the appointed frequency. the terminal charge and control equipment demodulate out the control single from data modulator and transmit it to the addressing control part, where the demodulated fsk single is received and well - handled by the cpu unit, decode the unauthorized signals and deliver it to the shut point, shut point make use of capability of wideband anf characteristic of shut, then the signal of illegal customer will be turn off and vice versa, the legal customer can receive the normal signal
前端數據調制器完成對計算機輸出的控制信號加密處理，將指令碼載送到一指定頻率點。終端收費控制器解調出控制信號，送至單片機尋址控制部分。單片機尋址控制部分接收經fsk數據解調器送來的信號，送入cpu單元后，解出不授權信號，然後向關斷部分送入信號，關斷部分利用pin二極體的寬帶工作能力以及關斷特性，實現對非授權用戶或者非法用戶的信號關斷，使之不能正常收視，繳費用戶進行開通正常收視，達到控制用戶通道的管理。The signal format of gps is analyzed, the principle models and mathematical models are established, the ber performance is analyzed in a channel interfered with wide - bandwidth awgn, narrow - bandwidth awgn, transmitted signal, single - tone signal respectively. based on the results above interference methods are discussed and simulated. then the performance of code acquisition and code trace of a digital gps receiver are discussed. the modem of linkl 1 and link4a are modeled and their ber performances are analyzed and simulated in channel s interfered with awgn, single - tone signal and multi - tone signal respectively
建立了jtids的收發終端的數學模型，分析它在噪聲干擾、相關干擾、互相關干擾下的誤碼性能，提出較佳的干擾方法和干擾碼型，並進行模擬模擬；分析了gps的信號格式，建立了gps的原理框圖模型、信號數學模型，並對其在寬帶噪聲干擾、窄帶噪聲干擾、轉發干擾、單頻干擾等情形下的誤碼性能進行了分析比較，提出相對較佳的干擾方法，並做了計算機模擬，針對一數字式gps接收機中擴頻碼捕獲與跟蹤環的特性進行分析；建立了link11和link4a數據鏈調制解調數學模型，對它們在噪聲干擾、單音干擾、多音干擾等下的誤碼性能進行分析，最後對干擾情況進行了模擬模擬。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。And the most advantage of ofdm is that it can convert high - rate data stream into the low - rate and reduce data bandwidth so that multi - path - fading can be transformed into flat fading in wireless circumstance
這種調制技術的最大的好處就是將高速的數據流，變換成并行的低速數據流，減小了數據帶寬，從而可將無線環境中的多徑衰落（頻率選擇性率落）轉換成平坦衰落。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。A / d samples the intermediate frequency signal. the digital signal proceeding part based on tigersharc dsp can process the baseband digital signal including the algorithm of baseband modulation, baseband differential detection and symbol synchronization, etc. digital up converter supports interpolation filter and complex mixer
A / d對中頻信號進行采樣，數字信號處理部分以tigersharcdsp為核心，負責基帶采樣數字信號的處理，實現基帶信號調制，基帶差分解調，符號同步的捕獲和跟蹤等演算法。The detecting accuracy of the beam drift would be improved, as a high performance acoustooptic modulator modulates the frequency of the laser beam drift signal far away from the power frequency, the double power frequency and high frequency noises
具體包括: 1 .利用聲光調制器將光束漂移量信號調制到遠離工頻及其倍頻干擾和高頻噪聲的頻帶段，以期提高光束漂移量的檢測精度。In order to increase processing rate of inserting filters, pipe line is used to satisfy if ( intermediate frequency ) modulation. 5. nco ( numeric controlling oscillator ) based on lab ( look - at table ) fully satisfy if modulation
研究了級聯內插濾波器在寬帶if調制中的應用;以及如何加流水線（ pipeline ）提高內插濾波器的處理速率，滿足高速中頻（ if ）調制要求。According to transcendent knowledge, this algorithm classifies modulation systems by computing instantaneous frequency and instantaneous bandwidth of signal and regarding them as modulation parameters
該演算法憑借先驗知識，通過計算信號的瞬時頻率和瞬時帶寬，並以此作為制式識別參數來判斷信號的調制類型。Chirp signal is a kind of pulse - compressed signal with large time - bandwidth products achieved through linear frequency modulation. it has high resolution in range because of its great bandwidth
線性調頻信號是通過線性頻率調制獲得大的時寬帶寬積的一種脈沖壓縮信號，具有大的帶寬，因此有高的距離分辨力。In this modulator, coplanar strips ( cps ) are used as electrodes for they support balance mode propagation of microwave, and this is a desired merit for common optical modulator. due to the miniaturized dimensions, the metallization thickness is in the order of skin depth and the conductor losses are not negligible
雖然由於金屬的趨膚效應，電場將集中在金屬表面，但在40g以上的頻率條件下，金屬的厚度和趨膚深度在一個量級，而且此時調制器帶寬受到限制的最大根源來源於金屬電極的微波損耗。The transform uses the scale of the signal to decompose and make self - adapting frequency band partition of the input signals. therefore the amplitude value and the modulating frequency of the flickering signal can be obtained. with the instantaneous frequency in this method, the present study also analyzes the signal in terms of both time and frequency, and thus gets the time at which the flickering signal occurs and terminates
運用該變換從信號本身的尺度特徵出發對信號進行分解的特點，對輸入信號進行自適應的頻帶劃分，從而求出了閃變的調制信號幅值和調制頻率;利用該方法中的瞬時頻率概念，從時頻兩方面同時對信號進行分析，從而獲得了閃變信號的發生時刻和終止時刻，得到了較好的檢測效果。Some modulation parameters, such as the carrier frequency and the symbol rate, can be estimated prior to the recognition of modulation types. such other parameters as the modulation index, the modulation frequency deviation, and the signal broadband can be further estimated after recognition
部分調制參數如載波頻率、符號速率在識別之前獲得，在識別完成之後可以進一步估計調制指數、調制頻偏、信號帶寬等其餘參數。In this paper they study a position - detecting system based on microprocessor and psd ( position sensitive detector ). the method is as follows : when the ac - signal from psd which is illuminated by modulated light source passes through an active band - pass analog filter, it filters the ac signal which represents the object light source. then the dc - converter circuit transforms it into dc - signal which is used to calculate the position
這一系統採用的方法是通過對位置敏感探測器psd受到調制目標光源照射后輸出的模擬交流信號進行有源帶通濾波，提取出代表目標光源的調制頻率成份，再將該信號轉變為用來參與位置解算的直流信號，然後選用單片機組成硬體電路，對直流信號進行採集處理並與計算機建立通信，把數據送入計算機進行位置解算，分析判別目標光源和psd器件的相對位置。分享友人