頻率色散 的英文怎麼說

中文拼音 [bīnshǎisǎn]
頻率色散 英文
dispersion of frequencies
  • : 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...
  • : 率名詞(比值) rate; ratio; proportion
  • : 色名詞[口語] (顏色) colour
  • : 散動詞1. (由聚集而分離) break up; disperse 2. (散布) distribute; disseminate; give out 3. (排除) dispel; let out
  • 頻率 : frequency; rate
  1. Shortwave channel is time varying transmission channel. it has dispersion in frequency and time domains. this characteristics hinds the data transmi - ssion at high speed and the correction of received data. in this dissertation i have analyzed the statistic characteristic of shortwa - ve channel, established the model of shortwave channel and simulated the rayl eigh fading distribution. the technology of spreading spetrum has been proved that it has the capability for anti - multipath and discerning multipath

    在短波通信中,由於通道的時間頻率色散,引起多徑展寬和多徑衰落,前者限制了數據的傳輸速,後者造成短波數據通信中出現突發錯誤,為了解決多徑效應對短波通信的影響,本文所做工作如下:首先詳細分析了短波通道的統計特性,建立其數學模型;其次分析了擴通信的特點,從理論上證明擴技術不僅具有抗多徑干擾能力,而且具有分離多徑的能力;介紹了傳統的rake分集合併技術的特點。
  2. The key components in laser gyro is he - ne ring laser, and the reciprocal action theory between light and medium is the base in studying the ring laser, use the lamb half classical theory, and on the base of density matrix theory, the optical brounch equation was established, which described the movement of amplifying medium atom in the ring syntonic cavity, and according to the medium polarize theory the self consistent equations was deduced, which describe the light intensity and phasic of the counter - propagating wave. on the basis of this equations, adopted the simulation software matlab and virtual instrument programming language labwindows / cvi, we can do some simulated experiments in study the phenomenas such as amplify and dispersive characteristic of medium, mode pushing effection, burned hole effection and pattern competition, lock - in of frequency and the characteristic of light intensity and phasic of the counter - propagating wave in laser gyro

    激光陀螺的核心部件為he - ne環形激光器,而掌握光與介質的相互作用理論是研究激光器的關鍵,採用拉姆半經典理論為主,在密度矩陣理論的基礎上,推導環形諧振腔中描述he - ne氣體增益介質原子運動的光學布洛赫方程,運用介質極化理論得出描述激光陀螺反向行波的光強、位相所滿足的自洽場方程組,在此基礎上,運用matlab模擬軟體和虛擬儀器編程語言labwindows / cvi ,對激光陀螺中的介質增益特性、牽引效應、燒孔效應及模競爭、閉鎖效應及環激光的光強和相位特性進行模擬試驗研究,並且運用全量子理論,對激光工作原理進行分析,得出二能級系統單模輻射場的光子數密度分佈,得出激光場的光子統計分佈,模擬激光場的動態建立過程。
  3. Through the analytic continuation of first order perturbation function in the - plane, we have that the integral path of dispersion equation should use the landau path

    。通過將一級微擾函數在整個復平面上解析延拓,得到方程中的積分路徑應採用landau積分路徑。
  4. The results show that, as for the single - mode transmission, the dispersion relations yet include space - dispersion ( k dispersion ) which relates to angular spectrum of fields of in - waveguide, in addition to the material - dispersion and the waveguide - dispersion

    分析結果表明:對于單模傳輸,關系中除了與有關的材料和波導外,還應包括與輸入端光場的角譜有關的空間( k) 。
  5. In section one, we analyze the mechanism of lwi gain, and study the effects of the rabi frequency q of the driving field, the injection rates ratio rb / r ~, the exit rate r0, the decay rates ~ and rab between atomic levels, as well as 3 incoherent pump rate r on the gain without inversion, dispersion and population difference of the system. in section two, we discuss the effects of the detuning of the driving field and the probe field on the gain

    在第一節中分析了無粒子數反轉激光增益產生的機制、研究了驅動場的rabi、粒子注入速比值r _ b / r _ c 、粒子退出速r _ o 、能級間的自發衰減速r _ ( c - b ) 、 r _ ( a - b )和非相干泵浦速r對增益、和粒子數差的影響;第二節討論了驅動場和探測場的失諧對無粒子數反轉激光增益的影響。
  6. This paper deals with the method of stress wave to measure the elastic modulus, loss modulus and their dispersion relationships against frequency of materials

    摘要用應力波的方法建立一維木材動彈模量的關系方程,並測量和分析了兩種木質材料的動彈模量與關系。
  7. In this paper, we study inversionless lasing of frequency up - conversion in an open v - type system with incoherent pump. making theoretical analysis and numerical calculation by density - matrix equations of motion, we derive the conditions for the onset of lwi and discuss the effects of the parameters of the system, the detuning of driving field and probe field on the gain, and discuss nonlinear effect in the frequency up - conversion regime. we also give stability and transient analysis

    本論文研究了具有非相干泵浦的開放v型系統上轉換無粒子數反轉激光,利用密度矩陣運動方程,通過理論分析和數值計算,得出該系統產生無粒子數反轉激光的條件,討論系統各參數的變化和驅動場與探測場的失諧對激光增益、和粒子數差的影響,還討論了上轉換區域的非線性效應,分析了增益的穩定性及系統的瞬態演化過程。
  8. In chapter 2, we analyzed the effect of the driving field phase fluctuation on the gain and dispersion and population differences in an open v - type three - level non - inversion lasing system and then discussed the effects of the incoherent pumping rate, the ratio of the atomic injection rates, the atomic exit rate, the rabi frequency of the probe and driving fields and their corresponding detuning on the gain, dispersion and population differences of the system, and got some important conclusions different from those in closed or other open systems

    第二章討論了驅動場的相位漲落對開放的v型三能級無反轉激光系統的影響,根據解析解的數值計算結果討論了非相干泵浦速、粒子注入速之比、粒子退出速、探測場和驅動場的rabi和相應失諧對系統增益、和粒子數差的影響,得到了一些不同於封閉的v型系統及其他開放的無反轉激光系統的重要結論。
  9. Two cold - test parameters determine the working voltage, frequency band, efficiency and gain of twt. they are dispersion and interaction impedance of the slow - wave structures ( sws ) in twt, which are very important targets for twt

    行波管慢波結構的和耦合阻抗是行波管設計中兩個非常重要的冷參量,它們決定了整支管子的工作電壓、帶寬度、工作效和增益。
  10. The dielectric constant of srtio3 ( sto ) thin films is voltage - dependent near the curie temperature tc ( about 40k ). and no dispersion in is observed in sto at frequencies up to 10 ghz. yba2cu3o7 - x ( ybco ) high temperature superconducting thin film has very low microwave surface resistance

    Srtio3 ( sto )薄膜在其居里溫度附近( ~ 40k )具有介電常數隨電場強度變化而變化的性質,同時sto在10ghz以下介電常數沒有頻率色散性。
  11. Then, the auxiliary fields fdtd is used to the periodic structure made of dispersive material, such as the pyramid absorbers in anechoic chamber. the permittivity vs frequency property of the absorber is approached by some dispersive equation model, such as debye model and lorentz model, so the broadband response of the absorber can be gotten through one calculation

    然後將輔助場fdtd應用到媒質周期結構中,導出了媒質中的迭代式,並以暗室吸波材料陣列為例進行計算,提出用某一類型的介電常數函數(如debye型、 lorentz型等)來逼近材料的介電常數特性的方法,從而可以對吸波材料進行一次性寬計算。
  12. The numerical results of the dispersion relation show some nonlinear effects : for a fixed geometry of a waveguid, beam parameters and plasma density, the increment of the modulation parameter may lead to a slight increment of the operating frequency, however, as the modulation parameter increases further, saturation may occur and the dispersion relations are hard to be separated, it is due to the overmodulation of the microwave power, this phenomenon itself belongs to the nonlinear effects

    對於一定的波導、電子注參量和等離子體密度值,等離子體調制系數的增加,使工作略微升高。但是,隨著等離子體調制系數的進一步增加,曲線變得彼此之間不可分辨,可以認為是等離子體的過調制導致了柵的飽和。這一現象是非線性的,可見,等離子體柵和調制場中文摘要是非線性關系,等離子體柵是非線性j 。
  13. The following algorithms have been proposed and tested in the thesis : 1 frequency selective fading : combine the isomorphism between the input space and the output space and propose a new approach to blind equalization of the channel. compared with conventional methods, the new approach offers lower computational complexity, better performance, and more robust against the over - determination of the system order ; 2 time selective fading : a new approach to the equalization of time selective channel based on the zero - forced equalizer is proposed which is more simple in its structure of algorithm ; 3 time - varying channel : using the instantaneous mean value changes of the output signal to extract the information of channel variations and model it using ar model, kalman filter is then employed to track channel variations, it bears faster ability in tracking the variation of tv channels ; based on the isomorphism between the inputs and the outputs and some of the approaches using in mimo system, a new algorithm of equalization of simo time - varying channel is proposed, which also share the merits of being robust against the over - determination of the system order ; model the time - varying channel using the multi - resolution decomposition wavelets, and then a blind identification method based " on the model is proposed ; at last, a new model for equalization and identification of mimo system is proposed

    主要工作在以下幾個方面: 1 、針對選擇性衰落通道:結合輸入輸出空間同構關系提出一種新的選擇性通道均衡方法,與傳統方法相比,該方法計算量更小,收斂速度更快,性能更優,且對系統階次的過確定表現穩健,具有實際均衡應用價值; 2 、針對時間選擇性衰落通道:提出一種基於迫零均衡的時間選擇性通道均衡方法,演算法結構簡單; 3 、針對時變通道:利用瞬態均值曲線提取通道時變信息,對之ar建模,利用卡爾曼濾波器跟蹤時變通道抽頭變化,可以快速跟蹤通道變化;基於輸入輸出空間之間的同構關系以及多輸入多輸出系統的處理方法,提出了新的單輸入多輸出時變通道均衡與識別演算法,同樣具有對通道階次過確定保持穩健的優點;結合小波多解析度分析提出一種基於小波模型的通道盲識別演算法;研究時變的多輸入多輸出系統的盲均衡與盲反卷積問題,給出一種時變系統處理模型。
  14. The first order nonlinear hyperpolarizabilities in second - harmonic generation process and electro - optical pockels effect are computed. the basis set effects in ab - mitio quantum - chemical computation are mainly studied. the correction to the nonlinear optical properties due to the electronic correlation energy is discussed and the relationship between the first order hyperpolarizabilities and the frequencies of the external electric field is also investigated

    計算了二次諧波振蕩過程和電光pockels效應過程的一階非線性超極化,研究了電子的相關能對pna分子的非線性光學性質的影響以及pna分子的一階非線性超極化與外加光電場之間的關系,並著重討論了量子化學從頭計算中基矢組的選取對計算結果的影響。
  15. A time - varying disperse channel is a channel that contain both frequency selective fading and time selective fading

    時變通道則是同時存在和時間選擇性衰落的通道。
  16. It finds that the radicals generated in plasma control the deposition process and the main bonding configurations of films are dependent on the ratio of cf and cf2 radicals in films. the films composed of cf2 and cc bonds can be obtained at microwave power above 560 w. the frequency dependence of dielectric constant ~ ( f 1 x 10 ~ ? x 106 liz ) ii and dielectric loss tan5 ( f = lxi 02 ? 1 x 1 o5hz ) follow a power law respectively and all show decreasing trends as frequency raised

    薄膜的介電關系( f = 1 10 ~ 3 - 1 10 ~ 6hz )和損耗關系( f = 1 10 ~ 2 - 1 10 ~ 5hz )均服從指數規律,隨的增大而減小;對薄膜的電導關系的分析表明,這種指數規律的介電關系與由缺陷中心之間簡單隧穿引起的跳躍導電過程有關。
  17. The study indicates that there are some differences between the multilayered films and the uniform films in the dielectric constant - frequency relation and capacitance - voltage chara cteristics. the report also analyses the mechanism of dielectric enhancement of the multilayered thin films prepared by the sol - gel process

    研究同時表明, batio _ 3 srtio _ 3多層膜與單層膜的介電頻率色散程度、 c - v特性和介電系數與溫度的關系均略有不同。
  18. In succession, the theory of chirped - pulse amplifier system is given in detail, firstly, studying from designing experimental light road and optical components to theoretical analysis, we par ' tly finished the system by ourselves. about ultr a - shoft pulse with a pulse - width of 9. 8f s and output power of 650mw and band - width of about l 20nm is output from oscillator source, secondiy, the stretching capacity of single grating four - pass stretcher is measured using abcd matrix combining collins function, and the effect of relativ e parameters to the streching ratio is also simulated. thirdly, a new type of disjunctional frequency moduiating function is provided according to the gain - narrowing and gain - saturation which are appeared in the co urse of amplification, under modulating the two effects are both controlled on some e xtent, fourthiy, the effect of ase that is often ignored by people is analyzed and the resolving methods are also given

    從光路、光學元件的自行設計到理論分析計算,初步建立了一臺實驗系統;採用abcd矩陣法結合collins公式計算了四通式單光柵展寬器的展寬量,並模擬了相關參數對展寬比的影響,對實驗具有指導意義;評價了再生放大器和多通放大器的優缺點,對放大過程中通常忽略的放大自發輻射現象( ase )進行了分析,並提出了相應的解決方法;針對放大過程中出現的增益窄化和增益飽和現象,對輸入種子脈沖提出了一種新的分段調制函數,實現了對增益窄化效應和增益飽和效應的共同抑制;提出了系統的材料(包括放大介質和光路中的普通介質)正是融合高階的來源。
  19. Frequency selective fading

    選擇性衰落衰落
  20. A coherent electromagnetic pulse in the range between the far - infrared and microwave region is used as a detection source. the amplitude of the wave is recorded by electro - optical or photoconductive sampling. after fast fourier transform, the amplitude and phase of the wave is given, then the complex refractive index standing for the absorption and dispersion of the material in thz region is extracted

    Thz ( 10 ~ ( 12 ) hz )時域光譜技術是20世紀90年代發展起來的一種新型的光譜測量技術,它使用介於遠紅外和微波之間的相干電磁輻射脈沖作為探測源,利用電光取樣或光電導取樣的方法直接記錄thz輻射電場的振幅時間波形,通過傅立葉變換得到測量信號振幅和相位的光譜分佈,進而獲得材料在thz波段的復介電常數,即及吸收等信息。
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