頻道變換 的英文怎麼說
中文拼音 [bīndàobiànhuàn]
頻道變換
英文
channel conversion-
To utilize the advantages of dsp chips, the system should be computing sources economical. according to digital signal processing theory, the poly - phase fir can help reduce the workloads of the ddc / duc. therefore, adding the complex carrier mixers, the channelization system ( a method of using a single wideband facility to transmit many relatively narrow - bandwidth signals. by subdividing the frequency spectrum used in the wideband channel ) can be formed utilizing the characters of fft
為了使開發出的軟體可以適用於高速dsp器件開發，節省系統資源，課題首先從數字信號處理的理論進行分析，得出可以利用抽樣率轉換的數字濾波器的特點，即多相濾波實現數字上下變頻計算負擔的減小，之後進一步將多相濾波器與頻譜搬移部分結合，通過公式的推導，得出可利用快速傅立葉變換的特點實現多路信號的通道化發射和接收的處理模型。Thirdly, it simulated the pumping circuit & dividing circuit with the widely used software matlab / simulink. the displacement of the rod piston and the impact of hydraulic are analyzed in the different input flow ( frequency of pump ) and different reversing time. it found out the cause of hydraulic impact ( one - to - one incorrespondence between the response time of dividing circuit and the operation time of rod piston ), and gave some methods to weaken hydraulic impact. in the final part of the paper, the reliability of the theory analysis is further verified by the experiment of hydraulic system
首先在流變學原理的基礎上，深入分析混凝土在輸送管道內的流動狀態，得出混凝土泵的負載特性方程；然後根據功率鍵合圖的建模方法，建立泵送迴路和分配迴路的數學模型，並運用模擬軟體matlab simulink對泵送和分配迴路模型進行了模擬，分析了在不同的輸入流量（泵送頻率）和換向時間下，活塞桿的位移和系統的液壓沖擊情況，找到了引起液壓沖擊的根本原因（即分配迴路的響應時間（固定值）與活塞桿的運動時間（變化值）不相匹配） ，並提出了相應的改進方法。It is shown by structural seismic response of four wavelets that littlewood - paley wavelet is not suitable for structural seismic response, because structural response is too small, meyer wavelet is a better wavelet for structural seismic response, for it ' s structural response is agreement with the finite element method, and also harmonic wavelet, structural response under earthquake is a little bigger than finite element method, structural response under odd exponent wavelet is also bigger than finite element method, this method is very simple by wavelet transform, wavelet transform method is different from old methods, one is with which not only knows the effects of earthquake wave detail frequency - band on structural response, but also considers earthquake wave ' s non - stationary of frequency and time - domain value, another is the second mode shape and higher mode shape response that do n ' t attenuate so fast
通過對這四種小波的結構地震反應分析研究說明： littlewood ? paley小波不適合於用來作結構地震反應分析，因為在littlewood ? paley小波下的結構地震反應太小，不符合實際情況；用meyer小波作結構地震反應分析比較合適，和有限元法的結果比較接近；也可以用諧波小波來作結構地震反應分析，只是在諧波小波下的結果略為偏大；單邊指數小波下的結構地震反應分析比有限元法稍大一點，它通過小波變換大大簡化了結構地震反應分析。用小波變換方法來進行結構地震反應分析和以往方法不同的是：它不僅可以知道地震波的具體頻率段對結構反應的影響，而且同時考慮了地震波的幅值非平穩性以及頻率非平穩性；另外與以前方法得到的結果有差異的是，第二振型及以後的高一點的振型的反應沒有以前的方法衰減得快。The design and application of ad6640 and ad6624 are fully discussed in this part. the design of software module includes the parameter design for ddc filter and the baseband signal processing of dsp. and the realization of the viterbi channel decoding algorithm by dsp and the simulation of the burst at the transmitter are discussed
模塊的硬體設計主要包括： a d轉換器、數字下變頻器（ ddc ）以及dsp ，詳盡討論了a d器件ad6640和ddc器件ad6624的設計和應用；模塊的軟體設計主要包括： ddc濾波器參數設計和dsp的基帶信號處理，給出了viterbi通道譯碼演算法dsp實現和發射端突發形成的模擬實現。In the previous studies, all - optical wavelength conversion is actuated by using light conversion and there has been no relevant report about the use of idle light
摘要在以往對全光波長變換的研究中，都是利用變換光實現波長變換，而利用閑頻光的全光波長變換還沒有相關報道。Plasma characteristics of a rf ion source are investigated by emission spectroscopy. the spatiotemporal spectral line intensities of the first three atomic lines in hydrogen bahner series ( = 656. 28, 486. 13, 434. 05nm ) of rf ion source plasma, are measured with calibrated optical multichannel analyzer ( oma ). some plasma parameters, including electron temperature, hydrogen atom density and hydrogen ion density, are calculated and analyzed using partial local thermodynamic equilibrium ( plte ) theory and abel transform
實驗採用絕對定標后的光學多道分析系統（ oma ）測定了離子源等離子體不同時間和空間位置的氫原子巴耳末譜線系中前三條譜線（ = 656 . 28 ， 486 . 13 ， 434 . 05nm ）的強度，並採用plte的理論和abel變換方法，計算出了高頻離子源等離子體的電子溫度、氫原子濃度、氫離子濃度等參數在放電的不同階段和徑向分佈情況，並進行了簡要分析。The main works and innovations of this thesis are as follows : ( 1 ) based on the oversampling of ofdm frequency response, this paper proposes a channel estimator which combines the comb - pilot - tones partitioning and the fourier transform with the same pilot symbol samples
具體而言，主要有以下六個方面的工作和創新點： （ 1 ）利用在ofdm系統中通道的頻域響應是過采樣的特性，提出了在頻域內用均勻梳狀分佈的導頻符號和與導頻符號數相同點的傅里葉變換相結合的通道估計方法。In this paper, a variety of familiar signals and channels are firstly analyzed and then the methods of dft and cyclic correlation are introduced
本文在分析各種常見的通信信號和通道的基礎上，採用了離散傅立葉變換和循環相關方法解決信號載頻偏差的高精度估計問題。Secondly, basing on single channel if sr receiver mathematic model, this thesis has designed if sr receiver subsystem and brought forward its design project and system circuit principle diagram, and explained the system working principle. furthermore, this thesis introduces the working principles and respective applications of wideband high - speed adc ad6640, ddc ad6620 and high - speed dsp tms320c6713 according with the if sr receiver subsystem high - speed analog digital conversion department, digital down conversion department and high speed digital signal processing department. thirdly, the thesis emphatically demonstrates the software realization department of the if sr receiver subsystem, which including ad6620 ' s inner parameter software setup, tms320c6713 data transmission and processing and the quadrant demodulation algorithm program realization
其次，基於單通道中頻軟體無線電接收機數學模型，本文設計了中頻（ if ， intermediatefrequency ）軟體無線電接收機子系統，給出了中頻軟體無線電接收機子系統的設計方案和系統電路原理圖，說明了系統工作原理，並分別對應系統中的高速模數轉換部分、數字下變頻部分、基帶數字碩士學位論文軟體無線電理論研究及中頻軟體無線電接收機子系統設計信號處理部分，介紹了高速adcad664o ，數字下變頻器（ ddc ， digitaldownconverter ） ad6620 ，高速數字信號處理器（ dsp ， digitalsignalproeessor ） tms320c6713的工作原理，以及它們在中頻軟體無線電接收機子系統中的應用。Fourier transform cannot offer entire information of signals, namely frequency information presenting to any period of time cannot be confirmed on earth. although, short time fourier transform can obtain local information, it is difficult to find a " good " time window to fit for every period of time
傅立葉變換不能提供信號完全的信息，即不知道頻率信息究竟出現在那些時間段上；短時傅立葉變換雖然可以獲得局部信息，但是對於一個時變的非穩定信號我們很難找到一個「好的」時間窗口來適應各個時間段。This paper introduces a bispectrum - based channel estimation algorithm to improve the accuracy of the channel estimation at pilots and proposes an equalization method with the view of the reduction of the interpolation error
為了提高通道估計的精度，本文分別從提高導頻處通道估計精度和減小插值誤差的角度出發提出了基於導頻雙譜的通道估計演算法和基於變換域濾波的插值方法。Also discussed the methods on how to realize the cwt both in time - domain and frequency - domain and how to design the gm - c bandpass filter used in realization of cwt. in order to optimize the performance of gm - c filter, linearization techniques are investigated and proposed. due to process variation and parasitics, an automatic tuning is designed for center frequency / 0 and quality factor q also, in this thesis, 16 - channel analogue cmos cwt circuit has been realized
論文圍繞連續小波變換的模擬電路實現這一熱點問題，討論了連續小波變換的時域和頻域實現方法；具體分析了并行結構與串列結構的優缺點；研究了頻域法中的跨導-電容帶通濾波器的設計；給出了改善跨導輸入級傳輸特性的線性程度並擴大線性范圍的具體方法；設計了片內自校正（可調諧）環節使濾波器參數自動調整到設計標準值；最後給出了16通道濾波器組實現小波變換的方法。However, to the essential of communication technology, those techniques are all change in transmission medium or channel. recently, because of the development of dsp, ifft / fft, 46 / 128 / 256qam using in high - speed modem, and gradual introduction of new coding technique, soft decision technique, channel self - adapting, guard interval, ofdm ( orthogonal frequency division multiplexing ) arouse more and more attention. as a technology of high - speed transmission, ofdm can resist isi effectively
近年來，隨著dsp晶元技術的發展，傅立葉變換反變換、高速modem採用的64 128 256qam技術、柵格編碼技術、軟判決技術、通道自適應技術、插入保護時段、減少均衡計算量等成熟技術的逐步引入，正交頻分復用ofdm （ orthogonalfrequencydivisionmultiplexing ）作為一種可以有效對抗信號波形間干擾的高速傳輸技術，引起了廣泛關注。So you can switch to any band, you don ' t have do hardware interventions or similar staff likes pull the adapter cable out
這樣你就能切換到任何頻道，你不用改變任何硬體或類似的工作，只要拔掉適配器的電纜。Because using ofdm, a frequency - selective fading channel can be transformed into multiple frequency - flat fading sub - channels, in the coding process, spatial diversity ( due to multiple antennas ) is integrated with frequency diversity ( due to delay spread ), therefore, the proposed code can provide higher diversity gain than space - time code alone
該編碼利用正交頻分復用把頻率選擇性衰落通道變換成平衰落通道的特性，同時引入了基於多天線的空間分集和基於時延擴展的頻率分集，比空時編碼具有更高的分集增益。At the beginning of this thesis, we introduce the fundamental of the acoustics and the perceptual mechanism. next, different kinds of speech processing methods including time processing and time - frequency analysis are presented, such as short time average energy, short time cross zero analyses, short time autocorrelation function analyses and fft. at last, we focus on the sound separation, especially on single channel sound separation
在這篇文章開始的部分，我們介紹了聲學的基礎知識和人類聲音感知的機理;接下來，我們給出了在時域處理和頻域處理語音信號的一些經典的技術，比如短時平均能量分析、短時過零分析、短時自相關函數分析、快速傅立葉變換等;本文重點從理論和實驗上討論語音分離，特別是單聲道語音分離的演算法及其在分離音樂鼓點中應用。Hence, this paper focuses on fast channel estimation algorithms for ofdm - cdma receivers. we use comb pilots to estimate the channel response, and propose a low - complexity discrete fourier transform based mmse channel estimator
採用梳狀導頻進行通道估計，提出了一種低復雜度、基於離散傅立葉變換的最小均方誤差的信估計演算法。分享友人