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phase modulation

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phase modulation 【無線電】調相，相位調制。

【無線電】調相，相位調制。 “phase“ 中文翻譯：   n. 1.形勢，局面，狀態；階級。 2.方面，側面。 3 ...“modulation“ 中文翻譯：   n. 調整，調節；(聲調的)抑揚，變化；【音樂】轉調，變 ...“modulation; phase“ 中文翻譯：   調相“frequency modulation phase modulation“ 中文翻譯：   調頻調相“pulse modulation; phase modulation (pm)“ 中文翻譯：   脈波調變“amplitude-phase modulation“ 中文翻譯：   振幅相位調制“bearing dependent phase modulation“ 中文翻譯：   取決于方位角的相位調制“bearing-dependent phase modulation“ 中文翻譯：   方位角關連相位調制“binary phase modulation“ 中文翻譯：   二進制調相“biphase phase modulation“ 中文翻譯：   二相相位調制“bm bi-phase modulation“ 中文翻譯：   雙相調制“carrierless amplitude phase modulation“ 中文翻譯：   無載波幅相調制“cascade phase modulation“ 中文翻譯：   級聯相位調制, 級聯調相“code phase modulation“ 中文翻譯：   編碼相位調制“continuous phase modulation“ 中文翻譯：   連續相位調制“continuous phase modulation (cpm)“ 中文翻譯：   連續相位調制“crosby phase modulation circuit“ 中文翻譯：   克洛斯比相調制電路“differential phase modulation“ 中文翻譯：   差動式掂; 差動式調相“digital phase modulation circuit“ 中文翻譯：   數字調相電路“electro optic phase modulation“ 中文翻譯：   電光相位調制“four phase coherent modulation“ 中文翻譯：   四相相干調制“four phase modulation“ 中文翻譯：   四相調制“four-phase modulation“ 中文翻譯：   四相調制“hpm hybrid phase modulation“ 中文翻譯：   混合相位調制，混合調相“hybrid phase modulation“ 中文翻譯：   混合調相

phase rule

We derive an analytic expression of the group velocity dispersion ( gvd ) induced chirp and the self - phase modulation ( spm ) induced chirp in the normal dispersionregion of non - kerr - like optical fibers with saturable nonlinarity . the evolution of chirp is simulated by numerical methods . the studied results show that the more powerful saturable effects , the smaller is chirp and the gently is chirp . the net chirp is zero in the central region of the pulse 從理論上推導出具有飽和非線性的非克爾光纖正常色散區內，群速度色散效應導致的啁啾和自相位調制效應導致的啁啾解析表達式.利用數值解法模擬了非克爾光纖正常色散區啁啾演變過程.研究結果表明：當非克爾光纖的飽和非線性增強時，凈啁啾不斷減小，而且，越來越平緩，脈沖中心附近區域凈啁啾接近零

However , in the part of the software , the schemes to programme coder and decoder are expatiated separately and the final flow charts are drawn after that . during the design of the coder , the selection of the information source and the modulation is discussed . according to the characteristic of the multi - phase modulation ml 在軟件實現部分,分別詳述了編碼器和譯碼器的編程方案并給出了最終實現的流程圖:編碼器的設計中論述了信息源和調制方式的選擇方法;而對譯碼器的最大似然算法則根據多相調制的特點進行了算法簡化和實現。

And consequently , the phase modulation dissipation arises from the strong phase mixing between the waves inside and outside the modulation layer , and the pump wave is strongly damped near the resonant layer of coronal loop . after above analytical theories , we combine the two part of work into an integrated model of coronal heating 由于位于共振層附近的相調層非常薄，那么，對應的位于這個薄層之內的pump波就會和在這個薄層之外傳播的pump波有強烈的相混作用，從而對共振層附近的pump波有很強的阻尼作用。

In this thesis , the signal express format and characteristic of pulse internal phase modulation and pulse external frequency agile is introduced , and the signal design is processed based on the demand of radar system , the restriction of parameter design and various code format 本文首先介紹了脈內調相脈間跳頻信號的表達形式和特點,并根據雷達系統的需求和參數設計的約束條件以及不同的編碼形式進行了信號的設計。

By following the way of studying the nonlinear effect as a whole , the influence of the spm and xpm to the phase matching condition of fwm is studied . from the achieved analytical expression it can be seen that the phase modulation can change the efficiency of the fwm 根據綜合研究非線性效應的考慮，本文研究了自相位調制及交叉相位調制對四波混頻相位匹配的影響，在一定的簡化下得到了解析的結果。

The origin of supercontinuum ( sc ) generation in optical fibers has been conjectured to be the interplay between fiber nonlinearities ( self phase modulation , cross phase modulation and raman self scattering ) and group - velocity dispersion ( gvd ) 光纖中超連續supercontinuum ( sc )譜的產生源于光纖中各種非線性效應(自相位調制效應、交叉相位調制效應，四波混頻效應及受激raman散射等)和群速度色散的共同作用。

The theoretical analysis and result of simulation indicate that the two - phase modulation reduces the switching losses 50 % relative to the quasi - optimum and the space vector modulation and overmodulation can generate higher voltages with low total harmonic distortion 分析表明二相調制方法相對于準優化方法減少開關損耗近30 ，空間矢量的調制與過調制可以大大的提高直流母線電壓的利用率。

Recently , frequency - hop communication has been widely used in many military wireless communication domain as a secure transmission mode . in frequency - hop transmission , phase modulation system has good performance and high frequency efficiency 跳頻傳輸模式下的數字相位調制系統具有較高的抗噪聲性能，且能有效地利用頻帶，實現數據的高速傳輸，是一種比較優越的調制方式。

Self - focusing and self - defocusing have their origin in the intensity dependence of the refractive index of the nonlinear medium . the picture becomes more complicated when two copropagating optical beams affect each other through nonlinear cross - phase modulation 當兩光束共同在非線性介質中傳輸時，兩光束由于交叉相位調制效應將會相互作用，其物理機制變的比較復雜。

This work mainly studies the influence of cross phase modulation ( xpm ) on dwdm systems and schemes to suppress the influence . in addition , all - optical wavelength converter based on xpm in optical fiber is studied 本文主要研究密集波分復用系統中的一種重要的非線性效應? ?交叉相位調制對系統性能的影響及減小其影響的方法，并研究基于光纖中交叉相位調制的波長轉換器。

When the pump power of the input pulse was lower , the enhancement on sc spectrum generation due to cross - phase modulation effect is more significantly . the cross - phase modulation effect increased the sc spectrum generation efficiency greatly 當輸入脈沖的泵浦功率較低時，交叉相位調制效應對超連續譜的產生的增強效果更為顯著，它極大地提高了超連續譜的產生的效率。

Chapter5 : the effect of cross - phase modulation ( xpm ) on pulse propagation and sc spectrum generation in a dispersion - flattened and decreasing fiber are researched . it is found that xpm could enhance the sc spectrum generation and increase the generation efficiency 研究結果表明，交叉相位調制效應對超連續譜的產生起到增強的作用，提高了超連續譜產生的效率。

But up to now , none of them are commercially available . among these technologies , wavelength converters based on cross - gain modulation , cross - phase modulation and four - wave mixing in semiconductor optical amplifier is the mainstream of research 其中，基于半導體光放大器中的交叉增益調制、交叉相位調制和四波混頻效應的波長轉換技術是研究的主流方向。

During these processes , diffraction , self - phase modulation , cross - phase modulation and physical distance between the beam centers all have important effects on the beams and the pulse beams propagation 在這些過程中，衍射、自相位調制、交叉相位調制、光束之間的間距等都對光束和脈沖光束在非線性介質中的傳輸產生重要的影響。

Uast is equipped with the complex radar system of both continuous wave pseudorandom code phase modulation and mono - pulse amplitude comparison ( crs ) , and crs measures and gets target ' s position information 在坦克超近反導系統中，裝備偽碼調相連續波與單脈沖幅度比較復合體制雷達，用于測量目標的位置信息。

The jamming of multiple noise and the polynomial phase modulation caused by non - uniform relative motion are the main problems in mmw doppler guidance radar signal processing 乘性噪聲的干擾和非勻速相對運動所引起的多項式相位調制是毫米波多卜勒制導雷達信號處理中所面臨的主要問題。

Finally , we study the effect of longitudinal wakefield in the propagation of intense laser in plasma and find that this effect leads to asymmetric self - phase modulation of the pulse 最后研究了尾波場效應對激光傳輸的影響，發現縱向尾波場效應將導致激光脈沖不對稱自相位調制。

The study based on self phase modulation mechanism and the effects of gvd on sc generation are mostly focused on by analyzing and calculating theoretically 本文主要研究群速度色散對光纖中自相位調制效應sc譜展寬的影響，分析了產生sc譜的物理機制。

In chapter 5 the jamming such as phase modulation noise , binary pseudo random sequence and multiple pseudo targets are discussed 第五章對雷達干擾進行了闡述，主要的干擾信號有連續噪聲調相干擾、偽隨機碼噪聲干擾、多假目標干擾。