寬頻帶傳輸 的英文怎麼說
中文拼音 [kuānbīndàizhuànshū]
寬頻帶傳輸
英文
broadband transmission-
In all kinds of complicated network, oriented linking and unlinking, communication frequency resource is strained, and bandwith to transmitting audio frequency signal is too restricted, complicated and fluky, while audio frequency data exponential have been increased in the last several years. under the circumstances, based on the research of predecessor, this paper studies wavelet analysis ' s maths gist and practices significance on signal process, and puts forward a optimized wavelet package condensation arithmetic to process audio frequency data, which gives attention to coding efficiency, multirate and compression delay. simulation experiment on the arithmetic has been done by matlab
針對無連接和面向連接的各種復雜網路環境下,通信頻帶資源緊張,音頻傳輸帶寬有限且復雜多變,而各種音頻數據又日益增多的局面,本文研究小波分析在信號處理方面的數學依據和在數據壓縮方面的實際意義,在前人不斷工作的基礎上,提出了一種優化小波包變換編碼方案用於音頻數據的壓縮演算法,兼考慮了編碼效率、多碼率和壓縮時延多個方面,並在matlab環境下做了模擬實驗,對各種音頻信號及多種小波函數做了模擬結果比較,實驗結果證明該演算法可以在一定計算復雜度下可以很好地改進壓縮效果,達到多碼率下實現實時編解碼的過程,在高速dsp晶元等硬體設備支持下,可以有效應用於實際復雜多變信源編碼。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。The factors limiting the frequency band of the wide - band amplifier are introduced. through analyzing the effects of the intrinsic parameters and parasitical on the frequency characteristics, a method of improving fr of mosfet by using short channel device and making mosfet work at the saturation region through raising vgs is put forward ; the effects of different kinds of circuit configurations on the frequency characteristics and the junction voltage on the voltage pattern circuit, current pattern circuit and frequency characteristics are analyzed. according to the linear theory of transconductance which is applied in the bit circuit, the current pattern amplifier circuit, current transfer circuit and output circuit which consist of mosfet and the wide - band amplifier composed of them are put forward
介紹了限制寬帶放大器頻帶寬度的因素,通過分析mosfet的本徵參數、寄生參數對頻率特性的影響,提出了採用短溝器件、使mosfet工作在飽和區、抬高柵源電壓等提高mosfet特徵頻率的方法;分析了不同電路組態對放大器頻率特性的影響、節點電壓對電壓模電路、電流模電路頻率特性的不同影響,根據應用於雙極晶體管電路的跨導線性原理,提出了採用mosfet構成的電流模放大電路、電流傳輸電路、輸出電路以及由它們所組成的寬帶放大器,獲得了良好的頻率響應。We study the cost of metro wdm in two aspects in chapter 2. for the aspect of components, a bidirectional optical add - drop multiplexer ( boadm ) using fiber gratings and circulators is designed, and is cheaper, simple and appropriate compenent for single - fiber bidirectional ring networks ( sfbrn ). for the aspect of network, after study the traffic - grooming problem and the cost of wdm ring networks, a layered network with a multi - hubs is presented to reduce the total number of the network ports
在第三章,我們搭建了一個可以實現多業務單纖雙向傳送的sdh wdm網路平臺,以單根50km光纖作為物理媒質,以mux demux的為單纖雙向復用器件,以sdh wdm為傳輸手段,採用mstp技術,通過接入vlan模塊建成一個單纖雙向傳輸的局域網,並以此為基礎通過接入圖像編解碼器實現單纖雙向視頻傳輸,為城域寬帶接入網的多業務實現提供了範例。In the past few years, there has been significant interest in digital video applications like video conferencing and video e - mailing over internet, video telephony over public switched telephone networks ( pstn ) and wireless networks, etc. by removing spatio - temporal redundancies existing in adjacent frames, motion estimation can reduce the coding bit - rate significantly
低速率視頻編碼技術已在許多領域得到了應用,如在pstn (公共電話網) 、無線網、 n - isdn (窄帶綜合業務數字網) 、 b - isdn (寬帶綜合業務數字網)上傳輸視頻會議、可視電話和無線手持終端等。Section ii describes the design approach and implementation of speech module on mcf5249 coldfire core. the speech codec optimizes g. 729a codes and added voice activity detection of g. 729b to save bandwidth ; the implementation of acoustic echo cancellation uses nlms algorithm and it can reduce echo though designing adaptive fir filter and speech detector ; the dtmf and cpt generate signal using two second order digital sinusoidal oscillators and detect signal by picking up the frequency information. but only get the frequency information is not enough in cpt detector, this thesis introduces a method
其中對語音編解碼器的設計採用優化g . 729a代碼達到設計要求,並在此基礎上加入g . 729b的靜音檢測模塊,以進一步降低網路傳輸帶寬;對回聲消除器的設計採用nlms演算法,通過設計自適應fir濾波器和語音檢測器達到回聲消除目的;對雙音多頻設計,信號發生端採用構造靜態參數表並通過二階正弦振蕩器產生信號,信號檢測端提取頻率信息以檢測信號;對呼叫進程音設計,除了類似雙音多頻的信號發生及頻率檢測設計外,還需要檢測信號持續時間,作者設計了一種基於匹配狀態表的方法以檢測信號持續時間。Though wide - band has been used widely, it ' s not wide enough to watch high - quality real - time video. futhermore, wiless communicaton has become a hot technology, it has limited band and unstable communication channel which result in high percentage of errorness in this situation, if people want to watch realtime video, it has high demand that video producer compress the video as small as possible when quality is good enough and receiver have ability of error resilience
另外,無線通信已經成為當前it領域的一個大熱點,對無線通信來說,帶寬就更加有限,並且傳輸線路不穩定,錯誤率高,在這種情況下,如果想通過無線網路在線觀看視頻,必然需要視頻發送端在保證質量的情況下對視頻進行盡可能的壓縮,同時提供強大的糾錯和抗錯能力。By directed acyclic graph model, video server can select correct substreams by network bandwidth and terminal capability to get any frame rate, spatial resolution but coarse granular scalability presentation of video
通過該模型,視頻流媒體服務器能夠根據網路帶寬,終端能力,正確地選擇子碼流進行傳輸播放。Arithmetic figure that new dvd that conduct and actions world the adoption arithmetic figure of the first style see the port dvi port to broadcast, three stars the dvd - hd938 to can output to have not yet the compression to see the signal, but have no to need to pass by few molds the conversion process, from but avoided the loss of the painting quality with lose true, deliver the real arithmetic figure signal to television the dvi port is a high take the ieee1394 port breadth port, its deliver the speed to attain 5 gbps, is more than ten times to deliver the speed. at the same time, need not proceeding of port of adoption dvi few mold conversion, can avoid to convert what process result in to lose true, from but real realizes the arithmetic figure deliver
作為世界第一款採用數字視頻埠dvi埠的新型dvd播放器,三星dvd - hd938能夠輸出未經壓縮的數字視頻信號,而無需經過數模轉換過程,從而避免了畫質的損失和失真,向電視傳輸真正的數字信號dvi埠是一種高帶寬的埠,其傳輸速度達到5gbps ,是ieee1394埠傳輸速度的十幾倍。同時,採用dvi埠不用進行數模轉換,可以避免轉化過程造成的失真,從而真正實現了數字傳輸。Nowadays, the tv guidance technique using analog signal in the procession of transmission has been mastered proficiently, the conventional analog signal is gradually replaced by the digital signal, because it has many disadvantages, such as its need for wider bandwidth ( 6mhz ), the fact of being vulnerable to the noise, its hardware system is very complex and very hard to establish a common standard, while it also has some problems in the system using digital signal, the main problem is its huge volume of data
視頻信號可分為:模擬信號、模擬和數字信號並存、數字信號。目前,傳輸過程中使用模擬信號的電視制導技術已經比較成熟,但其固有的缺點是:傳輸模擬視頻信號所需帶寬較寬( 6mhz ) ,傳輸過程易受干擾,且硬體系統復雜,不易標準化,使得其逐漸被數字信號所取代。The future wireless mobile communication systems are expected to provide ubiquitous, high - quality, and high - rate mobile multimedia transmission. however, hostile multipath fading radio conditions give rise to serious inter - symbol interference ( isi ) ; even worse, wireless channel are often time varying, which makes the system more vulnerable and more difficult to track the channel state. orthogonal frequency dvision multiplexing ( ofdm ), which is inherently resistant against isi, has invoked a popular research interest in recent years, and has been a promising candidate technology of the physical layer for future weideband high - date - rate wireless communications. notwithstanding, ofdm is much more vulnerable to errors of both time and frequency synchronization and to that of channel estimation, and how to obtain correct timing and channel estimation efficiently is highly critical to ofdm systems. the dissertation will focus on both of the aspects of ofdm systems mentioned above
但是無線環境的多徑特性造成通信系統中嚴重的符號間干擾,同時無線通道的時變性使得通道特性跟蹤復雜。而正交頻分復用技術( orthogonalfrequencydivisionmultiplexing , ofdm )正是一種解決符號間干擾的有效傳輸手段,因此ofdm技術作為未來寬帶高速率無線通信的物理層候選技術在當前引起了一股研究熱潮。但ofdm系統對定時同步誤差和通道估計誤差非常敏感,如何在ofdm系統中準確快速地實現符號同步和通道估計是至關重要的,本論文將重點針對這兩個問題進行討論。Multiband transmission permits a reduction in error probability in exchange for at least a twofold increase in bandwidth and carrier power
多頻帶寬傳輸能降低誤差概率,但其代價是速度及載波功率至少增加一倍The satellite - telecommunication has a serial of characteristic such as long distance, large coverage area, wide communication band, big transmission capacity, high quality, it has made a rapid progress in the last decades and become one of the most powerful communication methods today
而衛星通信具有通信距離遠、費用與通信距離無關、覆蓋面積大、不受地理條件限制、通信頻帶寬、傳輸容量大、適于多種業務傳輸、可進行多址通信、通信質量高等一系列特點,幾十年來獲得了迅速的發展,成為現代強有力的通信手段之一。But the bandwidth of the raw radar video is too wide to transmit directly in the common communication channel
但是雷達原始視頻信號頻譜很寬,要求傳輸設備有很寬的通頻帶,而且效率低、投資大。The system is developed by ourselves on the basis of the project which is titled. multimedia broad bandwidth network engineering and been responsible by the author of this thesis. the hfc network transmission based techniques of internet dual access, user set - top - box access, stock broadcasting, standard video broadcasting, distant education, etc. are addressed. this system can provide information highway to telecommunication and tv broadcasting to run multimedia services and be suitable for the status of our nation and the economic burden of our public
本論文以作者負責的項目「山東勝利油田多媒體寬帶網路工程」為背景,闡述了本單位自主開發的「基於hfc網路多媒體寬帶傳輸系統」的原理、功能和技術特點,論述了基於hfc傳輸網路下的: internet雙向接入技術和用戶端機頂盒接入技術及股票發送、準視頻廣播、遠程教育等高速數據廣播技術在hfc網路工程中的實現,說明了該系統能夠為電信和廣電全面開展多媒體增值業務提供一套適合我國國情、滿足我國公眾經濟承受能力的信息高速公路完整解決方案。Following atm and 1000m ethernet network, wlan is a hit point in the communication research field now, and is thought highly as the future of communication network
該方案克服了電磁波頻率資源的約束,能高速傳遞大容量信息,且相對成本低、安全性高,適合寬帶傳輸的要求。5. otherwise, the applicability of cube comer array in the wide spectrum high power solid - state laser facility was researched as a relatively absolute part in this paper. through simulation, the action of cube corner array to reduce beam ' s focal spot size was testified visibly, and the smoothing effect of beam ' s modulation caused by cube corner array was proved primarily on the wide spectrum condition
另外,作為一部分相對獨立的內容,本文對寬頻帶激光傳輸條件下採用角錐棱鏡陣列抑制低頻波前畸變的設想進行了探索性的研究,通過模擬模擬驗證了角錐棱鏡陣列具有抑制低頻波前畸變、提高激光焦斑能量集中度的顯著作用,並初步驗證了寬頻帶激光傳輸條件下近場振幅高頻調制的勻滑效應。The usual method to broaden the bandwidth of the pin diode switch is combining the pin diodes with stub filters : when under reverse bias, the didoe is part of the filter, the transmission bandwidth is broadened ; when under forward bias, the structure of the filter is destroyed, signal is isolated
Pin二極體開關展寬頻帶的方法一般是把pin二極體結合進短截線濾波器,使pin二極體在反向偏置時作為濾波器的組成部分,以展寬開關在傳輸狀態下的頻帶;當二極體正向偏置的時候,濾波器的結構被破壞,起到隔離的作用。Broad - band coaxial - cable transmission
寬頻帶同軸電纜傳輸Wbt wide band transmission
寬頻帶傳輸分享友人