頻分制 的英文怎麼說
中文拼音 [bīnfēnzhì]
頻分制
英文
frequency division system-
In the thesis, a signal processing scheme of polarization - insensitive fiber optic michelson interferometric magnetic sensor is described : making the interferometer work near the quadrature with closed loop controlling working point method, the fundamental frequency component of the magnetic field sensing signals can be detected to measure the input direct current ( dc ) magnetic field by phase sensitive demodulation
本文主要介紹了偏振無關光纖michelson干涉型微弱磁場傳感器信號處理的方案:通過閉環控制工作點演算法使干涉儀工作在正交工作點處,再利用相敏檢波演算法提取傳感器輸出信號的基頻分量,以測量直流磁場的大小。The constituent elements and operating principle of the system are introduced in brief, and the functions of its components are described in detail
簡要介紹了電泵變頻控制系統的組成及原理,並對其各部分的功能做了詳細敘述。The carrier wave is modulated directly by the baseband signal at several frequency point in l band and s band. firstly, this paper clarifies the theory of i / q modulation, elaborates evm and acpl, and analyzes the effect of amplitude and phase unbalance and dc offset on evm. secondly we review the basic principle of phase locked loop and it ’ s composing parts, including the basic conception and design method of pll frequency synthesizer, especially introduce the charge pump pll frequency synthesizer in detail
首先,在闡述i / q正交調制基本原理的基礎上,通過對誤差矢量和鄰近通道功率泄漏的詳細分析,定性、定量地討論了各種非理想電路因素(如相位不平衡、幅度不平衡、直流偏差等)對調制器性能的影響;其次,介紹了鎖相環的工作原理和基本組成部分,包括鎖相環的設計和環路濾波器的設計,特別詳述了電荷泵鎖相頻率源;第三,介紹了採用直接調制技術模擬衛星信號的射頻前端的設計;最後,對整個直接射頻調制系統進行測試,結果基本上達到了課題要求。Cross - components suppression is always the intractability in the studies of tfd and the difficulty in signal processing we should overcome. on the other hand, the cross - components have much information of two ( or more ) signal components, so it is suitable for signal detection
因此,抑制交叉項一直是時頻分析研究領域一個十分棘手的問題,同時也是時頻分析得以更廣泛應用於各信號處理領域所要克服的網難之一。The image rejection mixer is composed of two unit mixers, rf is halved as two parts in quadrature ; lo is halved as two parts in phase ; if is synthesized in quadrature
鏡頻抑制混頻器包含兩個單元混頻器,射頻正交功分,本振同相功分,中頻正交合成。Inverter has been widely applied to the industry manufacture arid the process control, but it is rarely applied to the water system of the building air - condition system
摘要就變頻控制技術在樓宇集中空調水系統應用中,在不同季節、不同氣溫下電能消耗情況進行了分析。This thesis analyzed the error performance of mfsk and mpsk modulator in hf with optimal receiver, studied the shortcoming and strongpoint of several typical short - wave data transmission systems and their performance over fading and intersymbol interference channels. the theory and key technical of adaptive modem is discussed. in the last, an efficient modulation scheme - block coded modulation is introduced into hf radio systems to improve the efficiency of hf data transmission, this paper also proposes a hf data transmission system scheme composed of a block coded modulator and a decision feedback type adaptive equalizer
本文在對短波數傳兩種常見調制方式fsk及psk最佳解調性能分析的基礎上,討論了幾種採用典型調制技術的短波數傳系統(如時頻調制、多進制頻移鍵控慢跳頻、 chess系統)原理、優缺點以及抗衰落和抗符號間干擾的性能;分析了自適應串列數傳系統抗短波通道衰落和多徑干擾的原理、關鍵技術;在本文的最後引入一種有望解決短波數傳系統低效率狀況的調制方式bcm -分組編碼調制,給出了一個採用bcm技術與自適應均衡技術相結合的短波數傳系統方案,並通過計算機模擬進行了初部驗證。The second chapter simply introduces the development of alternate asynchronous inverter technology and retrospects some types of energy - saving systems for hydraulic elevators. then the working principles of the project are discussed and analyzed at four different working status, i. e. light load upwards, heavy load upwards, light load downwards and heavy load downwards. and the chapter focus on the introduction of structure design of pump station, calculation and type selection of pump / motor reversible units, research on oil leakage principles of accumulator circuit, design of accumulator - pump / motor pressure - energy transformer and integrated valve blocks, etc. the last but not the least, the electrical wiring of vector inverter control cabin and design of computer control and data acquisition system are introduced
論文第二章首先簡單介紹了交流異步電動機變頻調速技術的發展概況,在回顧電梯液壓控制系統節能技術的基礎上,介紹了本課題研製的「採用蓄能器的液壓電梯變頻節能控制系統研究」的基本原理,分析了動力系統在電梯轎廂輕載上下行、重載上下行等四種典型工況下的基本工作狀態和工作方式;詳細地介紹了本課題節能系統液壓動力泵站的結構設計和參數設計,重點研究了液壓動力泵站的結構設計、液壓泵馬達可逆性問題及其選型設計計算、蓄能器迴路泄漏油損失機理的研究及其補償裝置的設計、蓄能器-泵馬達壓力能量轉換裝置的設計、多功能集成控制閥組的設計等內容;最後簡單介紹了本課題矢量控制變頻控制櫃的外部附件電氣接線、計算機控制及數據採集系統的硬體設計等內容。Firstly, introduce the basic conception of the telemeter and the telecontrol system ; discuss the common department of the telemeter and the telecontrol system, and the angle modulation used by it ; summarize the structure and function of the telemeter and telecontrol
首先,對遙測遙控系統的基本概念作了介紹;在此基礎上,對遙測遙控系統共有部分? ?信息傳輸部分進行了討論;對研發遙測模擬組合系統的中頻調制器所用到的角度調製作了介紹,它也是無線遙測遙控系統信息傳輸的一個重要組成部分;對遙測遙控系統的組成及其功用作了一定的概述。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。Secondly, introduce discrete multi - tone modulation principle in detail, have a systemic and comprehensive analysis and explanation on minimum mean square error ( mmse ) channel shorten time domain equalizer design methods which are based on all kinds of cost functions, analyze their advantage and disadvantage. research on time domain equalizer structure, compare all the time domain equalization algorithm with simulation which afford a valuable reference for the choice of equalization algorithm and equalizer structure when design time domain equalizer
詳細介紹離散多音頻調制原理,對mmse通道縮短法和基於其他代價函數的時域均衡器設計方法的進行了系統全面的分析和闡述,分析了各自的優缺點;對時域均衡器結構進行研究;模擬比較了各種時域均衡方法,為進行時域均衡器設計時均衡演算法、均衡器結構的選擇提供了有價值的參考。It realizes the functions of storing and transferring the information of fire alarm, displaying time, scanning keyboards, the safe maintenance of system and so on. the part of wireless communication is controlled by at89c2051 mcu, mainly realizing transmitting and receiving data between controller and other detectors. the external signals received by a wireless module are transmitted to mcu through shaping circuit, and the signals of mcu are transmitted by a wireless module through tone modulation circuit
人機交互部分以單片機c8051f020為核心,為用戶提供一個良好的操作環境,實現了火災報警信息的存儲及調用、時間的顯示、鍵盤的掃描、系統的安全維護等功能;無線通信部分由單片機at89c2051來控制,主要實現控制器與其它探測裝置之間信號的無線發射和接收,無線通訊模塊接收到的外部信號經過整形電路送入單片機,單片機發出的信號經過音頻調制再由無線通訊模塊發送出去,這樣實現了數據的無線傳輸;本文還從節能的角度出發,兼顧性能的可靠性,提出了一種合理的無線火災報警的信息傳輸模式。However, the paralleling communication can meet the requirements of high speed and fidelity in underwater signal transmissions. ofdm is a kind of novel paralleling transmission technology. the principle of ofdm is that the whole bandwidth can be divided into some subchannels, the high - speed serial signal stream is modulated by some orthogonal subcarriers
正交頻分復用( ofdm )是近年來數字通信中流行的一種并行傳輸新技術,其核心思想是將整個可用頻帶分割成多個正交子通道,將待傳輸的高速串列碼流并行的調制在這些子通道載波上。Turn over and close board part : vfc motor, round pan reduction drive, frame and rocker
翻板、合片部分:由變頻控制電機、原盤減速機、翻板支架及搖臂組成。Feeding and face fixing part : vfc motor, reduction drive, initiative, passivity drive roller. belt roller, face fixing, trimming and special width tape
輸送整形部分:由變頻控制電機、減速機、主、被動傳動輥、調帶輥、整形、修邊及特種寬面膠帶組成。And pays emphasis on analyzing the system structure and system flow, the core techniques, the channel characteristic and parameters of dvb - t system. the system adopts some core techniques such as cofdm, a lot of tps ( transmission parameter signalling ) insert and guard interval, and so on. so it can withstand high - level ( up to odb ), long delay static and dynamic multipath distortion
論文首先描述了數字電視地面廣播的需求條件,技術難點和目前存在的問題,並重點分析了dvb - t系統結構流程,核心技術及系統通道特性和參數,該系統採用了cofdm (編碼正交頻分多路復用) ,大量導頻信號插入和保護間隔技術等核心技術,使之能抵抗高電平( 0db ) ,長延時的靜態和動態多徑失真,有利於數字和模擬電視的混合傳輸,它的多載波調制模式功能和性能在移動和便攜接收、同頻網等方面具有獨特的優勢。The suitable oil flux during the circulating of transformer could be defined according to the difference of temperature between the oil and wind in the inlet and the cooling capacity of the wind cooling system ; besides the oil flux can be determined by ultrasonic, it can be estimated whether the oil is flowing equably by determining the oil flux in the branch pipes ; reducing the oil flux of the oil pump could be realized by controlling to change its frequency, which could not only save the energy, reduce the wastage, but benefit the transformer ' s circulating safely
變壓器運行中可根據進口油溫和進口風溫之差、風冷卻器的冷卻容量來確定合適的油流量;油流量可以通過超聲波法進行測量,測量油的分管流量還可判斷油流的均勻情況;降低潛油泵流量可通過潛油泵的變頻控制來實現,不僅節能降耗,對變壓器的安全運行也有著重要意義。In the aspect of blind - identification, the mutual power spectrumx time - frequency distribution product of two delay signals are used as the features of classification. the cluster analysis and cumulant invariants of mpsk signals are used to automatically classify communication signals
在信號識別中,選取信號的互功率譜、時頻分佈、 mpsk信號的延遲相乘信號作為分類特徵,利用模式識別中的聚類分析以及mpsk信號的基於高階累積量構成的分類特徵不變量實現了信號調制類型的自動分類。Telemetering system of frequency division type
頻分制遙測系統General technical condition of frequency division on off signal transmission unit for coal mine
礦用頻分制開關量信號傳輸裝置.通用技術條件分享友人