高頻有線通信 的英文怎麼說
中文拼音 [gāobīnyǒuxiàntōngxìn]
高頻有線通信
英文
high frequency wire communication- 高 : Ⅰ形容詞1 (從下向上距離大; 離地面遠) tall; high 2 (在一般標準或平均程度之上; 等級在上的) above...
- 頻 : Ⅰ形容詞(次數多) frequent Ⅱ副詞(屢次) frequently; repeatedly Ⅲ名詞1 [物理學] (物體每秒鐘振動...
- 有 : 有副詞[書面語] (表示整數之外再加零數): 30 有 5 thirty-five; 10 有 5年 fifteen years
- 線 : 名詞1 (用絲、棉、金屬等製成的細長的東西) thread; string; wire 2 [數學] (一個點任意移動所構成的...
- 通 : 通量詞(用於動作)
- 高頻 : high frequency
- 有線 : wired有線傳真 wirephoto; 有線電報(術) wire telegraphy; 有線電話 electrophone; line; telephony; ...
- 通信 : communication; communicate by letter; correspond
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Technique of transmitting data via power line ( pl ) , a new technique developed in recent years , is used to automatize the free collecting system in public service and the management of uptown service 。 this article discussed the advantage , disadvantage and the current state of the power line carrier communication 。 the advantage , method and current state of using spread spectrum technique in power line communication are discussed 。 then the characteristic of low voltage power network was also compendious analyzed 。 in this paper , after introducing the principle of ssc , design of hardware and software of the system are been discussed 。 this system has been put into use , the result has proved its high stability and reliability
本文研究旨在提供一種利用低壓電力供電網路、低成本、高可靠地實現公共事業收費自動化和小區物業管理智能化的技術應用。討論了電力線載波通信的優、缺點及現狀,擴頻技術在電力線載波通信應用的優點、方式和現狀,並對低壓電力線網路的特性進行了簡單的分析。在闡述了擴頻通信的基本原理的基礎上,本文詳細地介紹了電力載波遠程抄表系統的具體實現,包括硬體模塊和管理軟體本系統已投入運行,具有較高的穩定性和可靠性。As the key block of the wireless communication transmitter in rf, it is very useful in improving the output power and efficiency, lowering the loss of the supply, lowering the size and the weight, lengthening the time of communication. class e power amplifier which is suitable to amplify envelop signal is very important in modern communication system
功率放大器( pa )作為無線通信射頻發射機中不可缺少的關鍵電路,對于提高手機的功率效率、降低電源損耗、減小體積重量、延長通話時間有著舉足輕重的作用,而適用於恆包絡信號放大的e類功率放大器,更是在現代通信系統中佔有十分重要的地位。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。Once has the bandits and thieves to intrude guards against the place, the detector launches the wireless coded signal immediately, the networking center number which installs when is apart from defense area 150 meter within the main engine to send out the police whistle sound to report to the police immediately, reports to the police dials to establish in advance or reports to the police the telephone, the handset number, answers in the police telephone to return puts user pre - record to report to the police the pronunciation, long - distance reports to the police, simultaneously comes the real - time transmission through the internet to deploy troops for defense, to withdraw from a defended position, to report to the police and so on the condition, inquires the historic record through the computer network
該系統還採用美國進口原裝晶元與先進的無線數字高頻技術微電腦cpu控制器主機組成。在防範地點安裝好主機后,並設置在布防狀態。一旦有盜賊闖入防範地點,探測器立刻發射無線編碼信號,安裝在距防區150米以內的主機立即發出警笛聲報警,報警時撥打預先設定的聯網中心號碼或報警電話手機號碼,接警電話里回放用戶預錄的報警語音,遠程報警,同時通過網際網路來實時傳遞布防撤防報警等狀態,通過電腦網路來查詢歷史記錄。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。The clues and techniques to improve the resolution of data processing are 1 ) removing the affection of near surface factors on data acquisition, including static correction and noise eliminating technique etc, 2 ) broadening the frequency band of pre - stack seismic data, including amplitude compensation and pre - stack deconvolution etc, 3 ) improving s / n ratio of high frequency and weak reflection signals through multiple coverage with high precision velocity analysis, residual static correction and high - order nmo, raising " dead line of high frequency reflection ", and 4 ) identifying post stack effective reflection frequency band, enhancing dominant frequency and so on
主要包括:消除近地表因素對資料採集的影響,包括靜校正和噪音壓制技術等;疊前拓寬地震資料領帶,包括振幅補償和疊前反褶積技術等;藉助高精度速度分析、剩餘靜校正和高次項nmo技術,通過多次覆蓋疊加,消除資料中隨機噪聲干擾、提高資料信噪比,尤其是高頻端反射信息的信噪比,改善高頻反射和弱反射信號信噪比,提高「高頻反射死亡線」 ;疊後有限反射頗帶識別、抬高優勢頻率等。Indispensable for high quality optical carrier signal reception in a large dynamic range, agc analog optical receivers are widely used in the optical transmission of radio and microwave signals, such as fiber catv, direct broadcast satellite tv, wireless communication and radar
摘要自動增益控制模擬光接收機廣泛應用於光纖有線電視、光纖直播衛星電視、無線通訊及雷達等射頻微波信號光傳輸,是實現大動態范圍光載波信號高質量接收必不可少的一項技術。It is necessary in digital communication system that carrier recovery can compensate frequency offset and phase jitter brought by transmission and modulation. this paper is mainly focused on carrier recovery technique. we introduce the channel model at cable headed and receiving site. firstly, we introduce the principle of carrier recovery and give some algorithms of them, which are directed - decision, reduced constellation and frequency sweeping
本論文緊緊圍繞著數字通信系統中的載波恢復技術,在介紹了有線通信系統所用的調制解調通道模型后,首先闡述了載波恢復技術的思想和基本原理,在此基礎上給出了三種載波恢復演算法,即判決導向演算法、簡化星座判決演算法和掃頻演算法,並且給出了其各自的模擬圖:然後深入研究了一種適合高階qam並且能糾正較大頻偏的載波恢復技術:極性判決演算法。Optical code division multiple access ( ocdma ) technology possess the characteristics of combating interference, high frequency efficiency, security, and simply network protocol, random access, so it is competitive to apply ocdma to wireless optical access network
光碼分多址( ocdma )技術具有的抗干擾能力強、頻率利用率高、保密性好、網路協議簡單、支持隨機接入等優點,將其應用到無線光接入網中,不僅具有cdma技術的優點又保持了無線光通信的優點,實現二者優勢互補。Smart antenna may reduce coggege of electronic engineering of uestc, the cochannel interferences ( cci ), enhance the user capacity and spectrum efficiency, reduces the transmit power and electromagnetic interferences, enhance the transmit efficiency, dynamically divide cells in third generation cellular
智能天線技術應用於第三代移動通信系統中具有可以減小因頻率復用造成的共通道干擾( cci ) 、提高頻譜利用效率及增大系統容量、減小發射功率和空間電磁干擾、增加發射效率、對小區進行動態劃分等優點。This paper applies the technology of frequency agility to radio fuze which has been applied widely in the field of radaf and communication, and introduces a scheme of frequency agility and frequency modulation fixed - distance fuze which has good precision of fixed - distance and strong ability of anti - interference
本文將應用於雷達和通信領域的頻率捷變技術引入到無線電引信,提出了一種既具有較高定距精度,又具有較強抗干擾性能的新的頻率捷變調頻定距引信方案。Over - the - horizon radar ’ s beam - frequency is high frequency band and its wavelength is so long that the annate ’ s characters are very complicated when applicated on the ship. the character of coupling between cells and the environment must be measured to compensate in the radar signal process step. the ship - based over - the - horizon radar uses cfa ( crossed field antenna ) as array antennas ’ cell
艦載超視距雷達使用高頻信號作為發射頻率,其波長較長,在艦船有限的空間內,陣列天線的陣元之間的耦合與陣元與背景之間耦合都十分嚴重,必須測量陣列天線通道的幅相一致性,作為雷達信號處理的補償參數。Advanced fpga technology is introduced to improve the integration of digital circuits, and all digital circuits in the original module are integrated in the fpga chips, which could not only reduce the cost, but also improve the reliability and measurement precision of the circuits. high speed digital signal processor ( dsp ) is selected as the coprocessor instead of scm ; it can receive all kinds of commands sent from vxi, analyze and execute the commands, harmonize each section of the module and process the data. higher - conversion - speed comparator chip is adopted to convert the input signals being measured into square waveform signals which could be identified by fpga chip ; it can expand the measurement range of frequency dramatically
本文在原有vxi總線四通道計數器模塊的設計基礎上,通過對原模塊缺陷的分析,採用一些新的技術和新的電子器件來重新設計該計數器模塊:採用最新的fpga技術來提高數字電路的集成度,將原模塊中的所有數字電路全部集成在fpga晶元中,這樣不僅能節約成本,還能提高電路的可靠性和測量精度;採用高速的數字信號處理器( dsp )取代原有的單片機作為協處理器,來接收vxi發來的各種命令,分析命令、執行命令、協調模塊各部分的工作以及對數據的處理;採用轉換速率更高的比較器晶元將輸入的被測信號轉換為fpga晶元能夠識別的方波信號,能極大提高測量頻率的范圍;採用d / a轉換晶元和隔離運算放大器得到隔離通道所需的比較電平,該比較電平值能夠根據實際需求進行設置,能增強模塊的使用靈活性。In mimo systems, the signal can be sent and received through multiple antennas or antenna arrays. the combination of ofdm and mimo can effectively alleviate the problem of multi - path propagation, increase system capacity, and obtain more robust system capability, so they are considered as the main stream techniques of the future wireless communication system
Ofdm技術固有的抗通道多徑和頻率選擇性衰落特性以及mimo在提高系統頻譜利用率,改善無線通信系統性能等方面的巨大作用,使得這兩種技術的融合成為了下一代移動通信系統的必然選擇。For example, the, higher qulity video phone and video conference ; video store and display with higher resolution ; video communication in wireless network ; etc. but a key technology in all these application is video encode and decode
例如更高質量的可視電話和視頻會議,具有更高清晰度的視頻存儲和播放,無線網路中的視頻通信等。這些應用中一個關鍵的技術環節是圖像的壓縮和解壓縮。Smart antenna provides an efficient approach to solve frequency resource deficiency, improve the capacity and quality of mobile communication systems, and achieve anti - jamming and antimultipath
智能天線技術為解決頻率資源不足、提高移動通信系統容量和系統服務質量、抗干擾和抗多徑提供了有效的解決途徑。And the orthogonal frequency division multiplexing ( ofdm ) is given more and more attention in wireless area, because ofdm lessens the severe effects of frequency selective fading and improves the spectrum efficiency, and this technology has been indicated to become a key technology in the fourth moving communication
其中ieee802 . 11a協議中使用到的ofdm (正交頻分復用)技術,由於其先天具有抗多徑衰落及頻譜使用率高等特性,成為當代無線通信領域研究的熱點,並預示著為第四代移動通信的關鍵技術。Recently, multiple input multiple output ( mimo ) system which originates from the employment of multiple antennas at transmitter and receiver has many advantages such as large system capacity, high spectral efficiency. on the other hand, orthogonal frequency division multiplexing ( ofdm ) which bases on the orthogonal transmission of sub - carriers also has some obvious merits such as strong anti - multipath ability, high spectral efficiency. the combination of the two techniques mimo - ofdm, has become a hotspot recently and regarded as promising technique for future next - generation mobile communication systems
近來,在無線通信系統中的收發兩端同時使用多根天線的多入多出( mimo , multiple - input - multiple - output )通信結構,具有系統容量大、頻譜效率高等優點;基於正交的多路子載波并行傳輸的正交頻分復用( ofdm , orthogonalfrequencydivisionmultiplexing )技術,具有抗多徑能力強、頻譜效率高等優點,二者的結合,即mimo - ofdm技術,被認為是構建下一代移動通信系統的框架技術。Adaptive coding technology is often used to improve frequency efficiency of wireless communication system as we know that the adaptive coding scheme based on turbo codes has been carried out in 3g systems
自適應編碼技術可以有效的提高無線通信頻譜利用率,在第三代移動通信系統中已經成功的運用了基於turbo碼的自適應編碼技術。Wireless link adaptation technology, because of its high spectral efficiency, is becoming one of the key technologies in wireless communication system
鏈路自適應技術正是由於在提高頻譜利用率方面具有很強的優勢,從而成為無線通信中的關鍵技術之一[ 1 ] [ 2 ] 。分享友人