有耗媒質 的英文怎麼說
中文拼音 [yǒuhàoméizhí]
有耗媒質
英文
lossv medium-
Under some conditions, although for passive materials, when a plan wave incidents to the interface between a layered lossless material and a layered lossy material, the reflection coefficient of electric field may be greater than unity
在某種條件下，即使在無源媒質中，電磁波在有耗媒質和無耗媒質的交接面上，其組合反射系數可能會大於l 。A new standpoint produced from the study is that the guided wave system in the oil well is different from the normal circular wave guide, as the fluid is a conductive medium, and it allows the higher or lower frequency waves to propagate
通過研究提出了由於井內流體為有耗媒質，油井構成的導波系統不同於一般的圓波導，可以傳播高頻或低頻電磁波的新觀點。Secondly, two applications of gpml abc in modeling pulse radar are shown : one is detecting pipeline underground, and the other is its application to highway technology. thirdly, with back - projection algorithm, we have formed the image of tree - trunks. in summary, the application of fdtd in uwb fopen so far is impressive
然後，對適用於有耗媒質的gpml邊界條件的應用開展了深入研究，對脈沖雷達探測地下管道和測量高速公路瀝青層厚度進行了fdtd演算法模擬。First, the fundamental theory of the basic fdtd method and its application in the analysis of the electromagnetic properties of infinite planar periodic structures is summarized. the basic ideas of the auxiliary fields fdtd method is expressed and generalized to the situations of the 2 - d periodic structures, to lossy media, and to the curvilinear coordinate. the shortcoming of this method in the management of conformal grids is pointed out
首先總結了fdtd方法的基本理論及其在周期性結構電磁特性分析中的應用，闡述了輔助場fdtd方法的基本思想，把它推廣到二維周期性的情況和計算區域為有耗媒質的情況，再進一步推廣到曲線坐標系中，並指出了該方法在網格共形處理中的不利之處。Expressions in three kinds of perfectly matched layer ( pml ) absorbing boundary conditions is also given. second, the numerical theories of the auxiliary fields fdtd method is studied, including the stability of the differential equations and the numerical dispersive relationship. the stability of two kinds of differential formulations and three kinds of pml is compared, using a straight method depending on the pmax - t graph
更進一步，研究了輔助場fdtd方法的數值理論，對其微分方程、差代方程的穩定性進行了分析，比較了有耗媒質中的兩種差分格式和三種理想匹配層中的差分格式的穩定性，提出了一種通過p _ （ max ） - t曲線判定穩定性並求出穩定性條件的直觀方法，並導出了該方法的色散關系式。The conformal microstrip antenna with some unique character has been applied in many fields, especialy on speedy objects. in this paper, an efficient fdtd algorithm is introduced to analyse the microstrip antenna. firstly, the fdtd formula in descartes coordinate system and in cylindrical coordinate system are obtained from the time _ dependent maxwell equations using the yee algorithm in a calculating region where the dielectric parameters are independent of time and space. the choice of the space discretization units and the time discretization interval are discussed which are decided by the accuracy and stability respectively. the shape and setup of the excitation source are discussed too. the excitation source is chosen to be gaussian pulse in shape. secondly, the mur ' s first - order and second - order boundary condition are deduced in cylindrical coordinate system. the methods of transforming radiation fields from near zone to far zone in the frequency domain and in the time domain are presented when fdtd is applied to analyse the characteristics of far zone. finally, three kinds of microstrip antennas are analysed. they are a slot antenna that lies on a plane ground of a microstrip, a slot antenna that lies on a cylindrical ground of a microstrip and a microstrip line _ fed aperture coupled stacked rectangular patch antenna in cylindrical coordinate system
本文從麥克斯韋旋度方程出發，建立了笛卡兒坐標下無源空間中均勻無耗媒質的fdtd基本方程和圓柱坐標下無源空間中均勻無耗媒質的fdtd基本方程，詳細討論了fdtd法計算中時間步長和空間步長的選取原則以及激勵源的類型和設置；推導了mur一階和二階邊界條件在圓柱坐標下的差分格式；給出了在用fdtd法計算天線的遠場輻射特性時必需採用的頻域和時域近場遠場變換技術；最後用fdtd法計算了平面微帶縫隙天線、柱面共形微帶縫隙天線和柱面共形微帶層疊天線的輸入阻抗和遠區輻射場，並分析了天線的一些參數的變化對天線輸入阻抗的影響，得出了一些有用的結論。A simulation and modeling mechanism is studied and proposed for multirate transmission protocol. based on the wlan that adopts ofdm transmission technique, we first assumed that the small - scall fading and multipath in ofdm sub - channel is rayleigh, and large - scale path loss could be described by bi - linearity model, and then we analyzed the rationality
基於採用ofdm傳輸技術的wlan ，我們假設ofdm子通道的小尺度衰落服從rayleigh分佈，路徑損耗可以用雙線性模型描述，並對假設的合理性進行了分析，將決定速率切換的誤幀率等物理層性能參數和媒質控制協議有機地結合在一起，對多速率傳輸建模進行了有意的探索。Propagation characteristic of vital signals in lossy layered media
有耗分層媒質中生命信號的傳輸特性分享友人