多层平面介质波导辐射模

介绍一种精确计算多层平面介质波导归一化正交辐射模的方法，在全辐射模的情况下，为了保证模的正交性，给出了准奇模和准偶模的确定方法，这此方法地计算机编程，为模传播法的建立和实际应用奠定了基础，本文最后给出几个应用的实例。     

基于无人机智能视觉的输电线路全息全景重建

针对当前重建方法不能精确展现输电线路实际情况的问题,提出基于无人机智能视觉的输电线路全息全景重建方法。通过分析输电线路全息全景重建原理,采用无人机智能视觉技术对输电线路进行拍照,对输电线路全息全景图像进行采集和特征提取等预处理,跟踪图像特征,引入立体匹配算法,实现输电线路全息全景的重构。实验结果表明,所提方法输电线路重建精度高,视觉效果与实际相符,更具实用性及可行性。     

Even Modes of a New Transmission Line Based on Semi–Open Dielectric Rode

An original transmission line based on a planar waveguide splitter with central dielectric filling is proposed. A rigorous electrodynamics model is presented for calculating propagation and attenuation parameters of even eigenmodes. The presence of the lowest quasi–H wave having low dissipation loses was detected in the spectrum of hybrid modes. Numerical experiments prove that new line is very promising for different millimeter wave applications, such as antennae and three-dimensional integrated circuits (TDIC).     

ODD Modes of a New Transmission Line Based on Semi?open Dielectric Rod

An original transmission line based on a planar waveguide splitter with central dielectric filling is considered. A rigorous electrodynamics model is presented for calculating propagation parameters of odd eigenmodes. It was determined that the physics of the wave processes of the line for odd modes is identical to the physics of closed structures, though the structure geometry is of semi-open character. Numerical experiments prove that new line is very promising for different millimeter wave applications, such as band pass filters, test fixture, antennae and three-dimensional integrated circuits (TDIC).     

基于新型SCRLHTL结构的超宽带滤波器设计

提出了利用去除并联电感实现简化左右手（SCRLH）复合传输线（TL）结构的方法,及利用该方法实现超宽带滤波器的设计。设计了一个中心频率为7．05GHz、相对带宽约为70％、带内群延时小于0．4ns的超宽带滤波器。分别应用HFSS和Designer软件对该器件进行了微波全波仿真及电路仿真。用不同方法仿真获得的结果吻合良好。由此证明了用去除并联电感的新型SCRLHTL结构实现滤波器的正确性与有效性。     

透射光谱法测量滤光片参数的实验研究

利用海洋光纤光谱仪将光信号经分光系统和CCD阵列转换为各个波长范围的电信号,用Spectra Suite软件进行分析处理,获得相应的光谱信号曲线。实验结果表明,不同滤光片的透过率曲线不同,分析了滤光片透过的波长范围及其各自的透过率,通过各个滤光片的测试结果,了解各滤光片的应用领域。     

A New Transmission Line Microcavity Model for Vertical Cavity Surface Emitting Lasers

In this paper we present a new transmission line microcavity model for vertical cavity surface emitting lasers (VCSEL). The model is based on optical wave equations and implemented with state-space techniques to predict the lasing modes and analyze the decay properties of the Fabry-Perot (FP) cavities. The model is used to analyze microcavities in both time and frequency domains in terms of material and physical parameters of the lasers, and provide a simple and fast way to optimize the cavity length, reflective mirror and active region of the lasers.     

一种基于简化左右手复合传输线的带通滤波器

根据等效介质理论和Bloch-Floquet理论,研究了简化左右手复合传输线(SCRLH TL:Simplified Composite Right/Left Handed Transmission Line)的等效介质参量(ε,μ)、等效折射率(n)和传播参量(γB,ZB)的频响特性;设计、制作了中心频率约为7.49...     

Study of an Electromagnetic Wave Transmission Line Based on Coupled Dielectric Resonators

Doklady Physics - An analog of an optical waveguide in the form of a chain of metallic nanoparticles has been investigated using modified cylindrical dielectric resonators in the microwave band....     

基于遗传算法的30.4 nm多层膜设计

阐述了用遗传算法设计周期和非周期多层膜的原理和实现过程,完成了30.4 nm Mg/SiC周期和非周期多层膜设计,研究了遗传算法中不同种群数和多层膜膜厚取值范围对优化结果的影响.计算发现,种群数的恰当选取是使算法快速达到或逼近最优解的前提,膜厚取值范围的合理选择是提高算法效率的关键.设计得到入射角10°的周期多层膜和15°~22°范围内的宽角多层膜在波长30.4 nm处的反射率依次为56.57%与39.96±0.29%,5°入射的双功能多层膜在波长30.4 nm和58.4 nm处的反射率分别为54.1%和0.1%.结果表明遗传算法也是一种很好的多层膜设计方法.     

一种气体吸收的逐线计算模型及其实验验证

建立一种高分辨率的气体吸收光谱的逐线计算模型,分子谱线参数数据库采用了最新的低温库HITRAN2008和高温库HITEMP2010,能根据温度条件自动选择合适的谱带参数库,并可同时满足高温和常温气体辐射计算。计算波数采用等间隔取样,取样间隔大小以能分辨出典型分子谱线为条件确定。线翼截断采取等波数截断,总内配分函数由Gamache拟合三次多项式计算。谱线线型根据气体温度和压力来选择,最后,利用该模型计算了压力为1atm,不同温度、浓度和路径长度下CO2在4.3μm和2.7μm的透射率。考虑FTIR仪器增宽,将逐线计算结果降为窄带透射率,与中分辨率的试验结果对比均吻合,并能在较宽的温度范围内保证精度。     

Transmission line based struck string model

The analogy of a vibrating string to an electrical transmission line with the correspondences of the displacement to the voltage and the rigid end to the short circuit and the calculations for the hammer–string force in the well known finite difference form of the wave equation for a struck string are applied to build a transmission line based struck string model. The proposed model is validated by showing that the displacements and the forces exerted on the string at the contact with a hammer from the proposed model are consistent with those from the finite difference form.     

Study of a Composite Consisting of Metal Nanoparticles in a Dielectric Matrix and Multilayer Bandpass Filters Based on It

Doklady Physics - The frequency and concentration dependences of the effective complex permittivity of a composite consisting of silver nanoparticles in a polystyrene dielectric matrix have been...     

二维光子晶体层状超晶格透射特性研究

把平面波展开法(Plane Wave Expansion Method,PWM)用于数值研究圆柱柱体粗细及折射率层状间隔构成的二维光子晶体超晶格的传输特性.数值结果表明,层状超晶格的透射谱中禁带宽度在柱体折射率相同时与粗细柱体半径差异成线性关系,半径相差越大禁带宽度越小,禁带中心位置越向低频方向移动.在半径相同时禁带宽度与层间折射率差异同样成线性关系,折射率相差越大禁带宽度越小,禁带中心位置越向低频方向移动.因此人们可以根据实际应用中的禁带需要利用上述各种可调因素进行调节.     

激光入射角对干涉带通滤光片输出性能的影响

利用红外光谱分析技术,研究了激光入射角度对干涉带通滤光片输出性能的影响。激光入射角的变化对滤光片的峰值波长、峰值透过率等性能参数具有明显的影响;分析了中红外滤光片对3.8μm波段激光的透射性能,给出了滤光片的输出特性与入射激光角度的变化关系。     

铁氧体磁芯感应加速腔模型

 针对铁氧体磁芯,建立了以多层有损传输线为基础的同轴感应加速腔物理模型,并在短脉冲励磁条件下,通过低压及高压实验,结合PSpice电路模拟,对模型的准确性进行了验证,并由此间接推算出了铁氧体磁芯在不同情况下的平均脉冲磁导率和介电常数。实验和模拟结果显示,该模型能够准确地反映铁氧体磁芯感应腔在脉冲励磁下的动态物理过程,为感应加速腔实验结果分析、结构优化设计及磁芯性能选取提供了准确有效的方法。     

基于毫米波辐射特性的水面植被检测方法

针对采用3mm波段辐射计对水面植被辐射特性进行检测的问题,在研究分析了水面的亮度温度和水面植被的介电特性的基础上,采用相干法建立了水面植被辐射特性的多层介质模型,与3层介质模型相比,仿真结果与实验数据更加吻合,表明多层介质模型能更精确地模拟水面植被的辐射特性。通过实验得出,在不同的入射角下,水面植被亮温相比水面亮温均有上升,说明水面相比植被具有亮温低、冷目标的毫米波辐射特征,可利用毫米波辐射特性监测区域内水面植被。     

Transmission characteristics of multilayer films composed of electro-optic and dielectric materials

We describe the theoretical evaluation for the transmission characteristics of multilayer films composed of periodic electro-optic and dielectric materials in a variable electric field. The films are assumed to have cavity-type layer stacking structures, which work as a narrow bandpass filter, and their electro-optic material is uni-axial BaTiO₃, whose electro-optic coefficient r₅₁ is larger than 1300 pm/V. The evaluation indicates that films composed of BaTiO₃ and SiO₂ or MgO function as tunable optical bandpass filters, with a tunable range larger than 6 nm for an electric field of less than 4 V/μm.     

A comprehensive discrete-time computer modeling of acoustic Transmission Line loudspeakers

The Transmission Line loudspeaker is an audio loudspeaker enclosure topology devoted to extending the low frequency range near the loudspeaker frequency resonance. A few models based on physical properties of damped pipes have been proposed to characterize the Transmission Line loudspeaker systems. Unfortunately, Thiele/Small parameters, which are usually employed in enclosure designs, are not useful as parameters of design for these loudspeakers. In this paper, a comprehensive numerical formulation of a Transmission Line loudspeaker is presented, which is based in a finite difference approach of the governing equations, including the effects of the absorbing material allocated inside the pipe. The influence of the main empirical parameters is tested on the proposed model, which is also compared to a real prototype for validation purposes.     

新型透射式全息窄带带阻滤光器的光谱特性分析

滤光器在光谱学、光学测量和激光物理中有着极其重要的应用。全息滤光器是一种新型滤光器,特别是利用重铬酸明胶(DCG)记录的全息透射式窄带滤光器,其主要特点为对主谱线有很窄的带宽。文章主要用紫外-可见分光光度计测定用DCG记录的透射式全息窄带带阻滤光器的光谱特性,测量结果分析表明,滤光器在可见光区域(400～800 nm)对其中心波长的相对透射率小于2%,其他谱线的相对透射率大于85%。且滤光器有较窄的带宽,其半宽度小于12 nm,十分之一宽度小于15 nm。对氩离子激光(Ar+)主谱线514.5 nm有优良的滤光特性。