通信波段 的英文怎麼說
中文拼音 [tōngxìnbōduàn]
通信波段
英文
communication band-
And understanding and studying the spectral features and variation rules of geo - targets in the experimental area, raising that it is the basis of geo - targets information collection with imaging spectrometer data to understand spectral features and variation rules of geo - targets, realizing that in a great extent spectral - integrated - form - based classification method can remove the phenomenon of " different spectrum with same objects " resulted from reflection ratio curve translation because of the angle change among sensor, targets and observation direction, and the average and variance images can be introduced to solve the problem of two kinds of geo - target with similar spectral forms and much different values of whole reflection ratio. it is suggested that " red edge " range bands of vegetation, which has close relationship with vegetation cover and biomass, is the main characteristic bands and important basis for careful vegetation classification and quantitative retrieval, and pixel - based derivative spectral analysis is very useful for removing the effects of soil background values and quantitatively retrieving vegetation biomass and cover. the remote sense quantitative retrieval model is developed for main appraisable factors of desertification monitoring assessment with imaging spectrometer data and then the applicability of model is analyzed
研究結果如下:首先針對荒漠化地區的地物特徵,對高光譜數據不同波段的數據質量、波段組合進行了評價,提出了適用於荒漠化監測的基本波段選擇集;初步了解和掌握了研究地區的地物光譜特性及變異規律,進一步明確了掌握地物光譜特徵和變異規律是用成像光譜儀數據提取地物信息的基礎;發現了基於光譜整體形狀的分類方法在很大程度上能夠消除由於傳感器、地物目標觀測方向之間的角度變化引起的反射率曲線整體平移的「同物異譜」現象,對于譜形相似而整體反射率的值相差較大的兩類地物,通過引入均值和方差圖像參與分類得到解決;研究還表明在植被「紅邊」范圍內的波段是進行荒漠化監測的主要特徵波段,這些波段與植被生物量和蓋度都有密切的關系,是開展精細植被分類研究和植被定量反演的重要基礎;像元的導數光譜分析可以消除土壤背景的影響,是進行植被生物量和蓋度定量反演的有力工具;建立了荒漠化監測主要評價因子的定量反演模型,並分析了模型的適用性。Chapter five describe the real example of the project of dwdm. related with the project of the east - north loop of fiber transmission system, research the layout of the network, analysis the performance of the transmission and bring out the frondose project of construction, inculde the number of the wave length, the speed of the transmission, the style of he fiber etc. chapter six is the summary of the article
第五章是dwdm技術在通信工程建設中的實際應用,本論文以作者參與的一項具體的工程設計? ?中國移動集團公司建設的東北環光纜傳輸工程中dwdm技術的運用為實例,根據預測業務發展的要求,從傳輸性能的分析,到網路的規劃,技術上的實現,提出了其具體的建設方案,包括波長數目、傳輸速率、光纖類型、光復用段、設備制式等。Mixers are the key components of many microwave and millimeter - wave systems. the super - heterodyne receiver is always applied in modern communication system, mixer becomes the key component as is at the first part of system. but it is more and more difficult to get the choiceness lo source of the same band with the system is working at high frequency especially in the millimeter - wave. sub - harmonic mixer is a good solution to this problem now. in this circuit we need just half 、 quarter 、 even 1 / 8 of the rf signal frequency. in this paper the design and fabricate of sub - harmonic hmic mixers ( 2, 4 ) at w - band are introduced
混頻器是微波通信、射電天文學、雷達、等離子物理、遙控、遙感、電子對抗,以及許多微波測量系統中至關重要的部件。在現代通信系統中,毫米波頻段通常採用超外差接收機,混頻器作為第一級就成為關鍵部件。由於在毫米波頻段,同頻段高性能的本振源成本高,技術難度大,採用分諧波混頻技術是解決此問題的有效途徑,只需射頻頻率1 / 2 、 1 / 4甚至1 / 8的本振頻率即可實現混頻。This paper introduces the basic principle of the filter, expounds the structure of the spiral bandpass filter and the design method for the spiral bandpass filter based on the communication frequency, and proves this design method through testing
介紹了濾波器的基本原理,敘述了螺旋濾波器的結構以及基於通信頻段的螺旋濾波器設計方法,並通過實驗驗證了該設計方法。In modern shortwave communication, the length of signal existence time in single channel is very short for reducing the probability of being intercepted, thus the difficulty of signal detection and extraction increased
摘要在現代短波通信中,作為低截獲率通信手段之一,單個通道內信號持續時間大大縮短,從而增加了信號檢測與提取的難度。A temporal - spatial filter is designed for noise removing of clinical eeg signals, the first filtering is temporal filtering using band - pass filter, and the second filtering is spatial filtering with ica - based spatial filter
為了有效去除臨床腦電信號的噪聲和干擾,設計了一種時空濾波器,分兩個階段對腦電信號進行濾波預處理:第一個階段是時域濾波,用傳統的帶通濾波器實現;第二個階段是空域濾波,用基於獨立分量分析( ica )的空域濾波器實現。The major job is manufactured a transmitter, which has three upmixer channels. its function is to up convert the signals from c - band to ka - band. the input local oscillator is provided by a low frequency crystal oscillator which has a good performance of phase noise, through 512 times multiply to ka band. this sysetem is used in the laboratory as transmitter source of the fuze, for the multidimensional objects in practise, which lead to the complexity of the reflect signal, so the amplitude, frequency and the phase of the transmit signals both have a key role in dealing with the reflection signals. therefore, this system requires for both the coherence of the single channel ’ s amplitude, phase and multi channels
本文的主要工作是應用戶要求製作一具有三發射通道的上變頻系統,可以將c波段的微波信號上變頻到ka波段的毫米波信號。系統的本振輸入基頻由一相位噪聲非常好的低頻率晶振提供,經過512次的倍頻放大至ka波段。本系統作為實驗室中引信的發射源,由於目標反射信號具有時變的多維性,反射信號變得極為復雜,在信號處理時,不僅信號幅值、頻率有決定意義而且相位關系也很有決定意義。Based on research and experiments, we effectively improved the s - band tt & c transponder for satellite in such dimensions : with sensitivity up to - 92dbm ; dynamic range wider than 55db ; capture bandwidth of the receiver wider than 500khz ; capture time reduced to 22ms
通過論文工作,成功地改進了川于衛星的s波段測控通信一體機,跟蹤和捕獲接收靈敏度都能達到一92dbm ,動態范圍55db以上,接收機的捕捉帶寬大於500khz ,捕捉時問減小到22ms 。Minimum standards - citizens band radio service amplitude modulated transceivers operating in the 27 mhz band
最低標準.運行在27mhz波段的民用波段無線電通信業務調幅無線電收發兩用機The spectral region in the red or near infrared will be emphasized, because this is a region of low loss for optical fibers and therefore of interest for optical communication systems.
著重研究光譜區域是紅及近紅外波段,因為這是光學纖維低損耗的區域,也就是對光通信系統有意義的區域。In a tdma network, multiple users share the common medium ( or channel ) and bandwidth but different intervals of time. in case of the burst mode, the carrier of the modulated signal needs to be synchronized in a very short time. the common approaches such as a costas - loop and so on are no longer suitable any more
在一個時分多址( tdma )通信網路中,多個用戶通過不同的時間段共享一個傳輸線路(或者通道)的帶寬資源,每個用戶只能在分配給自己的時間段內進行通信,這種突發方式信號的解調要求載波恢復要在很短的時間內完成,我們以往在連續信號解調器中採用的costas環等方法很難適應這種要求。Short wave is used for wireless communication which the wavelength is from 10m - 100m. in fact, the high frequency part of medium wave usually belongs to short - wave band. so many short wave communication equipments ’ band was extended to 1. 5 - 20mhz
實際上,許多人也把中波的高頻段( 1 . 5 - 3mhz )歸到短波波段去,所以現有的許多短波通信設備,其波段往往擴展到1 . 5 - 20mhz 。Recently much attention has been paid to short wavelength lasers for use in high density information storage, information display, uv communication, medical treament & diagnisis, and so on, which make it become an important basal research with extensive application
由於紫外波段激光器在信息顯示和信息存儲特別是在海底探測,紫外通訊和光存儲,醫療和診斷,防偽和檢測,分析儀器等方面都有十分重要的應用,是一項具有重要應用前景的基礎研究。Wavelength division multiplexing ( wdm ) is an effective technique to meet the fast - grown demand for communication capacity
近年來光通信飛速發展,波分復用技術( wdm )是滿足要求的有效手段。Since the early 1990s, when the electronics industry came to the stage of digital technology, china has broken through in high - end series personal computers and servers, large - scale parallel computer systems, chinese electronic publishing systems, large - scale spc exchanges for central offices, mobile communications systems, sdh wdm fiber communications systems, thin route satellite communications systems, new generation digital video terminals, manufacturing technology for 0. 8 - 0. 35 m cmos integrated circuit chips, etc
到90年代進入數字技術階段,高檔系列微機和服務器產品、大規模并行計算機系統、中文電子出版系統、大型局用數字程式控制交換機、移動通信系統、 sdh波分復用光纖通信系統、稀路由衛星通信系統、新一代數字視頻終端、 08 ? 035微米cmos集成電路晶元製造技術等,都有突破性進展。So its naissance brings a lot of hope and promotion to application and deploitation of milimeter and submilimeter - wave. because of gyrotron, s superiority of high peak power and average power among many known milimeter and submilimeter - wave gyrodevices, it has been paid much respect in the world for application in many areas such as plasma heating, rf accelerator, millimeter radar, dew and so on
由於迴旋管具有在毫米、亞毫米波段其它器件無可比擬的高峰值功率、高平均功率的優越性,因此在受控熱核聚變等離子體的迴旋管加熱( ecrh ) 、電子高能rf加速、雷達系統、通信系統以及定向武器( dew )等方面都有著廣闊的應用前景。Short - wave communication is the most important scheme in military communication. with the fast development of various new technology and new systems, such as dsp technology, micro processing technology, frequency - hopping technology, error correction technology, short - wave communication has already been widely applied in military communication, marine communication, board communication and so on
短波通信是現代軍事通信中最重要的通信手段,隨著隨著數字信號處理( dsp )技術、微處理技術,自適應技術、跳頻技術,糾錯技術,分集技術等各種新技術和新體制的飛速發展,短波通信已廣泛應用在軍事通信、海上通信、機載通信等各方面。The article overviewed first of all the latest techniques realizing voa, then briefly introduced several polymers used on optical communications. furthermore, a few typical thermo - optic voa designs were illustrated and compared
本文首先綜述了目前用於voa設計和製作的最新技術,扼要介紹了幾種用於光通信波段的聚合物,舉例並比較了幾種典型的熱光voa設計。Owing to their unique optical properties, such as low loss and large refractive index difference between silicon and silicon oxide, soi structures can not only be used to fabricate smart integrate photonic devices, but offer the ability to integrate photonic devices into the cmos integrated circuit ( ic ) process
同時,它也具備許多優越的光學特性,比如低損耗(在通信波段) 、高折射率差,這使得它不但能用來製作靈巧緊湊的光集成器件,也為利用cmos微電子工藝實現光電集成提供了一個很好的平臺。If signal not pre - distorted, the variable capacity cv1 enables to correct the inclination of the transmitted pass band
以未預失真條件信號、這個同樣的標準,可變電容cv1賦予權利去校正已傳輸通道波段的傾斜度。分享友人