c-band c 中文意思是什麼
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Erbium - doped fiber - amplifier - c - band erbium - doped fiber - amplifier
摻鉺光纖放大器c波段摻鉺光纖放大器 -
Binary linear ( vertical and horizontal ) polarization is used by all chinese communication satellites, and binary circular ( right - hand and left - hand ) polarization is often used by some intelsat and some russian satellites in c - band
中國通信衛星都採用由垂直極化和水平極化構成的雙線極化頻率復用方式，國際衛星組織和俄羅斯的一些c頻段衛星則採用由左旋極化和右旋極化構成的雙圓極化頻率復用方式。 -
Design and implementation of a c - band frequency synthesizer
頻段頻率合成器的設計與實現 -
Then the c - band simple milo is simulated systematically. the physics of electron bunching and microwave field growing is investigated in detail
然後，對c波段milo模型進行了數值模擬，研究了其中電子聚束和微波產生的物理過程。 -
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。 -
This subject comes from the project : c band low phase noise tunnable jumping frequency source in chengdu saiying science and technology co, . ltd. the frequency synthesis technology of pll + mixer is adopted in the final scheme. at first, the developing history of the frequency synthesis technology is reviewed. then direct frequency synthesis technology 、 pll frequency synthesis technology are introduced
本文首先首先簡述了頻率合成技術的發展歷史，介紹了直接頻率合成技術、鎖相環頻率合成技術、 pll +混頻的頻率合成技術的基本理論以及具體的系統設計中應該考慮的方面。 -
According to the target distance ( 5 ~ 50m ), a c - band transceiver for ranging was presented in this thesis. the focus of this work was on designing a c - band frequency - modulated continuous - wave ( fmcw ) frequency source, a receiver and microstrip antenna
本文針對所探測目標的距離（ 5 ~ 50m ） ，研製了c波段測距收發前端，主要包括c波段調頻連續波（ fmcw ）頻率源，接收電路以及微帶天線。 -
For parameter a, there is a close relationship exist between a ( 9, sr ) in two different radar incident angle that can be expressed as : with considering the effects of soil texture, we get the final expression of the inversion model : where mv ( t1 ), mv ( t2 ) is volumetric soil moisture content in two different temp, c, d is soil type related parameters, and v ( t1 ), s ( t2 ) is coresponding bare soil radar backscattering coefficients. inversion results show that for the c band hh polarized radarsat scansar data with a range of incidence angle from 20 to 40, the soil moisture change value can be derived with an acceptable accuracy using the above model. the temporal and spatial soil moisture change patterns are associated with rainfall and vegetation cover, as well as the soil hydraulic characteristics
利用最新發展的電磁波散射模型研究了不同植被覆蓋地表雷達波對地表土壤水分的敏感性，建立了半經驗植被雷達後向散射模型; 2 ） .研究發現在農作物等矮小植被覆蓋地表，植被層直接後向散射與植被類型相關，且在植被生長期，雷達後向散射系數對植被含水量的敏感性要高於對植被高度變化的敏感性; 3 ） .解決了單參數雷達地表土壤水分反演問題中，雷達入射角和地表粗糙度的影響這一難點問題; 4 ） .利用土壤介電模型校正了不同土壤類型對反演地表土壤體積含水量的影響; 5 ） .在以上成果基礎上，建立了完整的單參數雷達地表土壤水分變化探測反演演算法，經地表驗證，模型反演地表土壤水分變化值的精度為rmse = 0 -
Numerical simulations of c - band three - cavity transit - time oscillator
波段三腔渡越時間振蕩器的數值模擬 -
Services included c - band satellite tv transmission, international satellite earth station tv transmission and video conferencing
包括Ｃ頻段衛星電視傳送、國際衛星地面站電視傳送和會議電視業務。 -
The experimental study is performed on the c - band tapered milo designed with the help of the simulation. the whole system is calibrated separately by parts. from milo to microwave receiving hom, the special system is simplified to be a two - port network and its s parameter is measured to calculate the attenuation factor a
對于微波功率的標定問題，我們根掘實驗條件，將整個系統劃分為幾個部分分別進行了標定，包括：從milo到接收喇叭組成的特定系統，將該特定系統簡化為一雙口網路，並測量出了其s參數，從而計算出與頻率密切相關的衰減量a ；對固定衰減器在不同微波頻率下的衰減量進行了標定。 -
To meet the waveform requirements, dds + multiplier + upconverter was used to realize the c - band fmcw frequency source
為滿足波形參數要求，本文設計了dds +倍頻+上變頻的c波段三角形調頻連續波頻率源。 -
In terms of the pic simulation, the output power of 1. 5gw at c band and 200mw at x band in milo have been obtained
用整體上移的辦法增加高次諧波，通過對輸出頻率的選擇，在x波段獲得了250mw的功率輸出。 -
The converter mainly accomplishes changing the c - band rf to intermediate frequency 70mhz, amplifying and gaining. the thesis includes r & d of local oscillator and group - delay equalizer. the thesis overall views the historical development future trend, introduces the theories, applications and characteristics
該變頻器主要完成雙通道c頻段射頻信號到70mhz中頻的變頻、放大和增益控制等功能，本文的主要工作是下變頻器中的本地振蕩器和中頻群延遲均衡器兩部分的研製。 -
Secondly, basing on the theory of on - off gain of small signal, the raman gain coefficient for frequency shift between 0. 5 and 20 thz of standard sigle mode optical fiber is measured by pump - probe method through a super luminescent diode ( sld ) as a broadband small signal probe source. thirdly, numerical simulation analysis of gain characteristic of raman fiber amplifier for c band wdm signal light is made according to the raman gain coefficient of the fiber measured before through target and four rank runge - kutta method. at the invariability of wavelength and maximum power of each of two pumps, schematic of powers of two pumps for best flatness on c band wdm optical gain was found out, at the same time, the factors of resulting in gain saturation is analyzed, too
本文首先應用經典的電磁理論對拉曼光纖放大器的工作機制進行了分析，然後，根據小信號理論推導出的開關增益求出了光纖拉曼增益系數的表達式，採用泵浦-探測波的方法，利用超輻射激光二極體（ superluminescentdiode簡稱sld ）作為探測光源，測量了所用標準單模光纖頻移為0 . 5 - 20thz的拉曼增益系數，之後根據所測得的光纖的拉曼增益系數譜對應用該類光纖構成的放大c波段wdm光信號的拉曼光纖放大器的增益特性採用打靶法和四階龍格- - -庫塔進行了數值計算，在給定了兩個泵浦光源的波長和最大功率后，找出了反向泵浦情況下使c波段wdm光源增益最平坦的兩個泵浦的各自最佳功率，同時也分析了導致信號光飽和的原因。 -
The subject derives from the project of " c - band down converter ", which is contented with the satellite testing and controlling system
為滿足衛星測控業務的要求、完成c頻段遙測信號的接收工作，本課題研製了c頻段下變頻器。 -
In this study, we demonstrate a technique using the multi - temporal c band hh polarized radarsat scansar data to estimate the relative soil moisture change. the experiment data from sgp97 covered a whole range of vegetation growing season and different type agriculture fields
研究證明，星載合成孔徑雷達（ sar ）得到的地表後向散射系數與地表介電常數有直接相關關系，從而能夠在水文模型要求的精度范圍內有效提取地表土壤水分信息。 -
The comparison between the results of calculation and measurement shows that the two results are in good agreement for the broad band antenna in the l band and the waveguide - coax converter of bj48 type used as antenna in the c band, with a difference of less than 0. 7db, and that the two results also agrees well in the x band for the waveguide - coax converter of bj100 type used as antenna, with an error close to 1db only at few points in the given frequency range
比對結果表明: l波段（加脊天線） 、 c波段（ bj48型波導同軸轉換作為接收喇叭）的模擬結果與實測結果符合得較好，誤差小於0 . 7db ;在帶內， x波段（ bj100型波導同軸轉換作為接收喇叭）的模擬結果與實測結果比較一致，只在個別頻率點處誤差近1db 。 -
A dynamic gain equalizer device including control circuit, mechanical structure and control program was designed using a cooler and a pzt. a dynamic gain equalizing experiment of the edfa using the designed dynamic gain equalizer was accomplished, and a 1. 2db flatness in the range of 32nm at c - band was obtained. finally, some future improvements were discussed in this
Iv .設計了一種利用製冷器和壓電陶瓷等來實現動態增益均衡器的裝置，設計了控制電路、機械結構和演算法程序，用這個動態增益均衡器對edfa的增益輸出譜線進行了動態增益實驗，實驗結果基本滿足要求，根據實驗結果，文中還討論了一些改進方案。 -
Finally, the production, which is designed and debugged all by myself, c band fine resolution low phase noise frequency synthesizer was introduced by module, including respective schedule, frequency distribution and phase noise experiment results. then whole circuit phase noise result, picture of spectrum with spur were presented, by which above theory was proved, analysis of the result was given, and the existing problem as well as methods to resolve it were motioned
論文最後對自己設計調試的樣機c波段小步進低相噪頻率合成器進行了分模塊介紹，包括各部分的原理框圖、頻率分配和相噪測試結果，然後給出了整個樣機的相噪、雜散頻譜測試結果，對上面提到的理論進行驗證，並對結果進行了討論分析，提出了樣機現存的一些問題和幾點解決措施。
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