特低頻通信 的英文怎麼說
中文拼音 [tèdībīntōngxìn]
特低頻通信
英文
vlf communication-
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。On the base of researching the theory of the scheme and analyzing the signal feature, it is obtained that the existence manners and character of distance information in the differential frequency signal. at the same time, a new conclusion is gained that the technology of frequency agility can decrease the constant error of system. it is also to say that frequency agility and frequency modulation fixed - distance fuze has the similar feature to random period frequency modulation fixed - distance fuze. according to the theory of address coding in the hopping - frequency communication, the paper presents the principle of selecting the frequency agility sequence which fit to the radio fuze and constructs the frequency agility sequence family based on the rs codes
在深入研究方案原理和分析信號特徵的基礎上,獲得了該體制引信差頻信號中,距離信息的存在形式和特點,得出了頻率捷變技術的引入降低了系統定距固定誤差這一新的結論,即頻率捷變調頻定距引信在定距性能上具有類似隨機周期調頻定距的特徵。本文引入跳頻通信地址編碼理論,結合無線電引信的具體特徵,提出了適用於無線電引信的頻率捷變序列的選擇原則,並構造了基於rs碼的寬間隔頻率捷變序列族。The apparatus, with the specialities such as miniature, automation, flexibility, and individual - computer managing has become the developing trendof the testing equipment today. based on analysis of the characteristic and the system structure of the visual instrument, the paper has studied the design idea of it, put forward the exploiting methods of the visual instrument based on the object - oriented technique, exoatiated on the technique kernel of design the visual instrument under windows environment, designed a typical visual instrument " vis - 1 signal - analyzing and wave - displaying system ", which integrates multi - function instruments such as general oscillograph and ulf oscillograph real - time signal recorder wave and frequency - pedigree analysis instrument. the system has more excellent functions and characteristics than traditional instruments
本文研究了虛擬儀器系統的設計思想,在分析虛擬儀器系統的特點及其體系結構的基礎上,提出了基於面向對象技術的虛擬儀器系統開發方法;闡述了windows環境下實現虛擬儀器的技術要點;實現了一個典型的虛擬儀器系統「 vis ? 1信號示波分析系統」 ,該系統集普通示波器、超低頻示波器、存儲示波器、瞬態信號記錄儀、波形及頻譜分析儀等多種儀器功能於一身,並具有許多傳統儀器難以達到的優越功能和性能。1 m 0. 5, the phase - shifted angle 6 is controlled in term of sine law which makes the magnitude of resonant voltage track a reference sine voltage, and the resonant voltage is rectified, filtered, inverted and then the better sine - voltage output is obtained, theoretical analysis and experimental results show that for the resistive load and inductive load, the switches of leading leg of the phase - shift - controlled circuit are always turned on at zvs, and ones of lagging leg are turned on at zvs ( < 0 ) or turned off at zcs ( ( > 0 ), moreover, all switches in the low - frequency inverter are always turned on and off at zvs, the measured circuit efficiency for rated load reaches up to 88 %
從功率單向流動角度出發,提出了一種lcc諧振型恆頻移相單相高頻鏈逆變電路拓撲,在調制系數0 . 1 m 0 . 5情況下,控制移相角按正弦規律變化,使諧振電壓脈沖列的幅值追蹤參考正弦電壓信號,經過整流、濾波、低頻逆變,從而獲得正弦度較好的輸出電壓。理論分析和實驗結果證明對于阻性負載或阻感性負載,移相全橋具有超前橋臂零電壓開通,滯后橋臂或者零電壓開通( _ 0 )或者零電流關斷( _ 0 )的軟開關特性,而低頻逆變器的各個開關均實現零電壓條件下的開通與關斷。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。According to the principle of spread spectrum communication, the anti - interference performance of the technology is discussed and the composition of power line spread spectrum communication is described. based on the spread spectrum technique, a method which is low cost, high communications quality and low bit error for power line carrier communication using single - chip software programming is proposed
利用擴頻通信原理,分析擴頻通信的抗干擾特性,在此基礎上,闡述了電力線載波通信系統的基本結構,提出了一種利用軟體編程實現電力線載波擴頻通信的方法。該方法不增加硬體成本,即能達到提高通信質量、降低誤碼率的目的。This paper presented a general systematic view, application and current development of the power line carrier transmission technology, and clearly compared some existing power line carrier communication chip with each other. then the authors analyze the channel " s characters of low voltage power line, and formed an abstract carrier channel model. using this as its basis, a new kind of transmission technology is designed that adopted transmission technology combining the spread spectrum modulation with channel coding, which can solve the problems above mentioned to a certain degree, and need not pay for high cost
文章不僅全面地介紹了電力線載波通訊技術的特點、應用及其發展狀況,還對目前的電力線載波通訊晶元進行了比較;並通過對低壓電網通道特性的分析和研究,抽象出其載波通道模型,在此基礎上,提出了將擴頻調制和通道編碼相結合的傳輸技術用於低壓電力線載波通信,這可以在很大程度上解決電力線的干擾問題,且不必付出高昂的代價。In this paper, they are set forth at first that the kinds of computer - simulation of electronic devices, the development and the requirements of mosfet ' s model and the way of gain the models " parameters, the dc models have been bui it in chapter 2 and the models of big signals have been deduced in chapter 3, they are different from the equivalent circuit models in the traditional software pspice that they come from the numer i ca i - s i mu i at i on wh i ch is based on the essence equat i on, so the precision of simulation is enhanced ? mosfet ' s small signal models of low frequency, intermediate frequency and high frequency have been built in chapter 4 and chapter 5, although the equivalent circuit models in pspice are used for reference to bui id them, they have their own characteristics which are analyzed at a i i kinds of situations, so that the simulation software for mosfet can be written according them and it i s a i so benef i c i a i for us to catch the gen i us character i st i cs of mosfet and to d esign all kinds of applicable devices the correctness of the models is simply proved in chapter 6
本文首先介紹了電子器件計算機模擬的分類、 mosfet的建模發展動態、對器件模型的要求以及模型參數的提取方法。在第二章中建立了mos晶體管在直流端電壓條件下的工作模型;第三章推導了mosfet的大信號模型,這兩類模型不同於傳統模擬軟體例如pspice中的等效電路模型,而是從模型方程出發,採用數值模擬的方法,提高了模擬的精度。第四章和第五章分別建立了mos晶體管低頻、中頻、高頻的小信號模型,雖然借鑒了pspice模擬軟體中用等效電路模型的方法,但是本文分別討論了準靜態和非準靜態時器件的本徵部分以及包含非本徵部分工作于低頻、中頻和高頻條件時的模型,可以根據這些模型編寫相應的模擬軟體,這樣在做器件的模擬分析與器件設計的時候,就可以利用模擬軟體逐步深入地分析器件在不同的條件下和器件的不同部分在工作時的各種小信號特性,有利於抓住器件工作的本質特性,設計出符合要求的各類通用和特殊器件。As a new communication mode, the spread spectrum communications are widely used in military communication, distance finding and precise position, because of its well multiaddress access, lowly capture probability, the excellent performance of anti - interference and secrecy
擴頻通信作為新型的通信方式,以其優良的多址接入、低截獲概率特性、抗干擾特性和強保密性被廣泛應用於軍事通信、測距與精確定位。In addition, the author puts forward that the eggs could be recognized based on the difference in the frequencies of their prompted sounds. because the eggs " prompted sounds are lied on low frequency bands, the microphone and sound amplifier that have excellent duration response should be used. the output signal from the sound amplifier is transferred to data signal by a / d card before it is put into computer
蛋品激勵出的聲音主要集中在低頻段,因此選擇在低頻段有好的頻率響應特性的麥克風和放大電路;放大輸出信號通過a / d採集板變換成相應的電壓數值信號送入計算機,對離散的信號數據進行傅立葉變換得到它的頻譜圖和各頻段能量分布圖;而後將能量分佈特徵數據作為神經網路的輸入值,這樣,好蛋和破損蛋的模型就建立起來。In this paper, the theory and implementing method of video encoder based on the itu - t h. 263 video coding for low bit rate communication standard are studied deeply in order to satisfy the demand of narrow - band video communication
為了在窄帶通道上實現視頻通信,本文對基於itu - t的低比特率視頻通信編碼標準h 263的視頻編碼器的原理和實現方法作了深入的研究。After that, it discusses the principle of the band - pass technology, illuminating the feasibility of the digital intermediate frequency system based on the sampling speed which is two times lager than the signal band but unsatisfying the nyquist theorem
隨后討論了帶通采樣技術的原理,說明可以使用不滿足奈奎斯特低通采樣定理但大於信號帶寬兩倍的采樣速率進行中頻數字化,減輕基帶處理負擔。Applying normal form method, conventional eigenvalue calculation and prony analysis, small signal stability and time domain simulation can be combined efficiently. the proposed method can get nonlinear information which never obtained by past techniques, so it shows a new way for analyze oscillation problems in interconnected power systems
通過正規形方法、小信號穩定特徵值計算技術、時域模擬、 prony分析的有機結合,達到小擾動和大擾動后低頻振蕩穩定性分析的統一,為互聯系統低頻振蕩分析開辟了新的思路。Compared with the similar research results, the weighted control ic here has the following characteristics : ( 1 ) the circuit structure is simpler ; ( 2 ) the chip ' s fabrication is compatible with standard cmos process ; ( 3 ) n - mosfets with high w / l ratio and short channels are used for weighting and output to reduce the insertion loss ; ( 4 ) the weighting factor varies in a relatively wide range with the controlling signals ; ( 5 ) input and output impedance approach 50 in low frequency ( e. g. 50mhz ), while in higher frequency they slightly deviate from 50, hence the energy reflection lower than 0. 1 ; ( 6 ) it completes the functions of sampling, weighting, controlling and summing of high frequency analog signals
它的加權控制電路與已報道的相關電路相比具有如下特點:電路結構簡單;製造工藝與普通cmos工藝兼容:短溝道,高寬長比的nmos晶體管具有低的通導電阻,將其作為加權、輸出器件可降低由電路引起的插入損耗;改變加權信號,可實現權值在較大范圍內的連續變化;輸入、輸出阻抗在低頻(如50mhz )下接近50 ,而在高頻下略有偏離50 ,但反射系數均低於0 . 1 ;實現了對高頻信號的取樣、加權、控制、疊加功能的迭加。The inductor, which is one of the most important magnetic components, is not only used in lc filter and choke but also in rf communication circuit. the thin film inductor can be integrated with semiconductor components, so far it has not been widely used in these fields, the reason is the limited of thin - film material and substrate, process technology and design technology. designing and fabricating thin film inductor is the key point of this paper
而作為磁性元器件中最重要的電感,它不僅在lc濾波電路、扼流圈中必不可少,在現代射頻通信電路中也被廣泛使用,特別是能與硅器件一起集成的薄膜電感器,在國際上備受重視,而國內長期以來,由於受薄膜磁芯材料、繞組材料、基片材料,包括製作技術及最為關鍵的設計技術限制,尚未研發出能夠用於這一應用領域的高、中、低頻薄膜電感器。In our paper, we firstly summarize the development of low rate video communication, before we implement h. 263 encoder to the adi ( analog devices incorporated ) evaluation board - - - - - adsp - bf535 ez - kit lite ; we make in - depth research about h. 263
本文首先概述了低碼率視頻通信的發展,然後對低比特率的視頻編碼標準h . 263進行了深入的研究;並在adi ( analogdevicesincorporated )公司的adsp - bf535ez - kitlite評估板上的實現了h . 263視頻編解碼器。Low bit rate video application based on pstn is one of the hotspots in the image coding field
基於pstn網路的低比特率視頻通信應用是當今圖像編碼領域的一個熱點,而itu - t的hSpread spectrum technique, which can handle variable adverse environments, exhibits unique qualities that have a number of advantages in anti - jamming, anti - noise, reduction of multi - path interference, low power spectral density, privacy, selective addressing and code division multiplexing
擴頻通信技術具有優越的抗干擾、抗噪音、抗多徑衰落性能,能在低功率譜密度下工作,具保密性、可多址復用和任意選址,能有效克服各種惡劣的通道特性,目前廣泛應用於移動通信、雷達、導航、測距、電力線通信等領域。In allusion to the problem mentioned above, a new scheme is brought forward in this paper. spread spectrum communication technology is applied in this scheme, which greatly improved the reliability of data transmission
本方案採用擴展頻譜通信技術,利用擴頻通信抗干擾能力強的特點,大大提高了數據傳輸的可靠性,實現了在中、低壓電力線上的進行遠程抄表的功能。But they have the disadvantages such as poor complexity, poor security and insufficient amount of sequence numbers among the family of codes, the chaotic signals have noise ? ike, broadband frequency spectrum, they can be used as spreading codes, furthermore, chaos system is extremely sensitive on initial conditions so that the various initial conditions given by chaos system can provide with large sum of spreading sequences and this can meet the demand of cdma, this thesis sets out to study on using chaos system to generate spreading sequence s, there are two parts is this paper : firstly, we study the basic theory of spread ? pectrum communication and the characteristics of chaos so as to prove the applicability of chaos system to be used in spread ? pectrum ii communication system
現在使用的擴頻碼有m序列, gold碼和r - s碼等,這些擴頻碼具有良好的隨機性,但普遍存在著復雜度低、保密性差以及同一碼族序列數目少等缺點。混沌信號具有類似噪聲、寬帶連續頻譜的特徵,正符合擴頻通信中對擴頻碼的要求,而且混沌系統對初始值極其敏感,可以通過給混沌系統賦予不同的初始值得到為數眾多、不相關的擴頻序列,這正好滿足碼分多址的要求。本文對利用混沌系統應用於擴頻通信作了一些研究工作,主要包括兩部分:第一部分:探討了擴頻通信的基本理論和混沌的基本特性,說明將混沌系統應用於擴頻通信系統的可行性。分享友人