Microstrip Transmission Line with Finite-Width Dielectric

The results of a numerical solution for open microstrip transmission line with finite-width dielectric are presented for a quasi-TEM computational model. The related solution is based on moment methods using equivalent source models for the free and bound charges existing on boundary surfaces. Characteristic impedance and velocity of propagation are presented in graphical form for estimating the effects of dieletric truncation on microstrip circuits and for related circuit design.     

Parameters of Microstrip Transmission Lines and of Coupled Pairs of Microstrip Lines

A theoretical analysis is presented of microwave propagation on microstrip, with particular reference to the case of coupled pairs of microstrip lines. Data on this type of transmission line are needed for the design of directional couplers, filters, and other components in microwave integrated circuits. The inhomogeneous medium, consisting of the dielectric substrate and the vacuum above it, is treated in a rigorous manner through the use of a "dielectric Green's function" which expresses the discontinuity of the fields at the dielectric-vacuum interface. Results are presented in graphical form for substrate dielectric constants of 1, 9, and 16, and a range of values of width and spacing of the strips. Numerical tables for these and other cases are also available. The tables present capacitance, characteristic impedance, and velocity of propagation of the even and odd normal modes. The method lends itself to the treatment of other geometries which are of practical interest, such as "thick" strips, presence of an unsymmetrically located upper ground plane, etc.     

Corner Function Analysis of Microstrip Transmission Lines

A new method of analysis of microstrip transmission lines using corner functions (eigenfunctions) is presented. Assuming the TEM mode propagation for the shielded microstrip line structure, solutions are set up in a series of corner functions, which isolates the singularity at the edge of the strip. The boundary conditions are satisfied by using a method of successive integration of boundary errors. Numerical results are obtained for the charge distribution from which the microstrip line characteristic impedance is determined. Excellent agreement with published theoretical results and experimental data is obtained. The numerical results clearly bring out the power of the method.     

An Analysis of Gap in Microstrip Transmission Lines

Although microstrip transmission lines have been widely used in microwave integrated circuits, the discontinuity structures in the microstrip transmission lines such as a gap, an abruptly ended strip conductor, and so on, have hardly been analyzed. An analytical method and numerical results for a gap capacitance in the microstrip transmission line are described. The equivalent circuit parameters are formulated with three-dimensional Green's functions, based on a variational principle. The numerical results are in good agreement with the published experimental data. The fringing effect of an abruptly ended strip conductor is also investigated.     

Multilayer Microstrip Transmission Lines (Short Papers)

A method used to treat covered microstrip is extended to multilayer microstrip. Detailed results are obtained for the general three-layer problem. Series expansion and term-by-term integration are used to obtain a closed form expression for the Green's function. Matrix methods are then used to obtain the characteristic impedance. Data obtained agree closely with experiment.     

An Accurate Calculation of Uniform Microstrip Transmission Lines

An analytical program for calculating the field distribution about a microstrip transmission line bounded by a shielding wall is used to calculate the impedance, velocity, and attenuation parameters. The program input parameters are the dimensions of the strip and shielding wall and the relative dielectric constant of the substrate material. The field distribution about the strip is integrated to find the charge density on the strip and walls with and without the dielectric substrate. From these two calculations, the relative velocity and impedance can be calculated.     

Broadband Via-Free Microstrip Balun Using Metamaterial Transmission Lines

A novel metamaterial broadband microstrip balun design is proposed. The broadband balun consists of a pair of identical metamaterial transmission lines. In the odd mode, a virtual ground is formed between the symmetric plane. The odd mode is allowed while the even mode is rejected. No vias are required to realize the shunt inductors of the metamaterial lines, and no power divider is used. Baluns with good performance can be achieved. In this letter, two baluns are fabricated and measured. For the balun with seven units, the output amplitude difference is less than 0.7 dB, and the differential phase is 181deg plusmn 3deg from 1.6 to 3.6 GHz, while the input return loss is greater than 10 dB.     

An Accurate Calculation of Uniform Microstrip Transmission Lines

An analytical program for calculating the field distribution about a microstrip transmission line bounded by a shielding wall is used to calculate the impedance, velocity, and attenuation parameters. The program input parameters are the dimensions of the strip and shielding wall and the relative dielectric constant of the substrate material. The field distribution about the strip is integrated to find the charge density on the strip and walls with and without the dielectric substrate. From these two calculations, the relative velocity and impedance can be calculated.     

A Frequency Dependent Solution for Microstrip Transmission Lines

Theoretical and experimental results of "open" microstrip propagation on both a pure dielectric and a demagnetized ferrite substrate are presented. The theory enables one to obtain the frequency dependence of phase velocity and characteristic impedance, and also to obtain the electromagnetic field quantities around the microstrip line. It utilizes a Fourier transform method in which the hybrid-mode solutions for a "fictitious" surface current at the substrate-air interface are summed in such a way as to represent the fields caused by a current distribution that is finite only over the region occupied by the conducting strip and is assumed equal to that for the quasi-static case.     

Finite Element Analysis of Lossy Waveguides-Application to Microstrip Lines on Semiconductor Substrate

The development of Maxwell's equations is made considering the electromagnetic fields as vector distributions. With the aid of the finite element method, an analysis of lossy shielded inhomogenous waveguides of arbitrary shape is described. To solve the complex matrix system an iterative procedure is presented. The method is applied to study the propagation on MIS or Schottky contact microstrip lines.     

An Analytical Method for Calculating Microstrip Transmission Line Parameters

When finite difference techniques are applied to the solution of coupled-line parameters for microstrip transmission lines, the computation times become prohibitively long. This paper describes an analytical method for calculating such parameters if TEM propagation is assumed. The method is applicable to a wide range of planar TEM mode transmission line calculations where the boundaries and dielectric interfaces are rectilinear. The accuracy of the analytical technique has been verified by experimental work on 10 dB and 6 dB coupled-line directional couplers and a parallel-coupled Cohn type 6 resonator filter.     

Miniaturization of Microstrip Branch-Line Coupler With Dual Transmission Lines

The dual transmission lines are proposed to replace conventional quarter-wavelength transmission lines for a compact microstrip branch-line coupler in this study. The developed coupler can be easily fabricated on the printed circuit board without lumped element; moreover, its size is greatly reduced compared to the conventional branch-line coupler. Furthermore, simulated and measured frequency responses match well to validate the proposed coupler with dual transmission lines.     

Rigorous Determination of the Parameters of Microstrip Transmission Lines

Statement of Problem--The purpose of this paper is to determine explicit expressions enabling calculation of the performance of the recently-introduced open-strip UHF transmission line, now rapidly coming into extensive use.     

一种新型传输零点可控的微带带通滤波器

提出了一种新型的传输零点可控的微带带通滤波器结构,它由一段低阻抗线和与之相连的平行耦合线构成。通过调节低阻抗线与平行耦合线的偶模阻抗比,可以改变谐振器的2个模式之间的距离,从而灵活的调节滤波器的带宽;而通过调节平行耦合线的间距,则可以方便的调节传输零点的位置。仿真与实测结果都表明该滤波器具有良好的性能：低插损,结构紧凑,可以灵活的调节带宽和传输零点的位置。     

一种新颖的槽形传输线微带环行器的研制

介绍了一种新颖的槽形传输线微带环行器，利用有限差分法计算了微带线的特性阻抗和等效介电常数，分析了环行器的各设计参量，给出了设计公式以及实验结果。实验表明，该环行器可承受１．２ｋＷ的峰值功率和２０Ｗ的平均功率。     

用于光纤传输系统的半导体激光放大器

本文主要介绍用于光纤传输系统的行波半导体激光放大器(TWSLA)。首先描述 TWSLA 的激光器刻面抗反射(AR)涂层的特性,然后描述半导体激光放大器(SLA)的重要特性,如小信号增益、信号增益饱和及噪声特性,最后讨论了 TWSLA 的结构设计。     

WDM-POLSK Transmission Systems by Using Semiconductor Optical Amplifiers

The authors demonstrate the potential of using POLarization Shift Keying (POLSK) modulation format combined with semiconductor optical amplifiers (SOAs) in wavelength division multiplexing (WDM) transmission systems. The constant intensity of the POLSK modulation format allows for substantial removal of cross-gain-modulation impairments in SOAs so that practical amplifier spacing values (more than 100 km) are demonstrated in various different experimental configurations. Record WDM transmission experiments at 10 Gb/s by using SOA-based amplification are presented in short and medium reach system architectures using either single mode fiber or nonzero dispersion shifted fiber     

用于无线能量传输系统的微带天线设计

本文提出一种用于组成无线能量传输(Wireless Power Transmission,WPT)系统的微带天线结构,并采用基于有限元法的电磁仿真软件(HFSS)对微带天线进行3D建模.在二端口网络分析法的基础上,建立磁耦合共振无线能量传输等效电路模型,求解出系统发生频率分叉现象产生的条件以及最大效率时的频率表达式.基于以上方法,研究本文设计的微带天线传输特性,包括:系统的最优传输效率与耦合距离的关系,工作频率与耦合距离的关系,得出在能量传输距离在50cm左右时,天线的谐振频率为12.5MHz,效率可达63%.微带天线具有很大的结构优势,如与集成电路兼容,成本低,体积相对较小,且工艺相当成熟,易大规模批量生产等优势.因此该设计的平面微带天线可用于无线能量传输系统.     

一种新型一维微带PBG单元结构

通过对传统二维微带 PBG 结构的研究,针对微带线的传播常数是微带线相对于接地板上周期孔眼的两个主轴的位置和方向的敏感参数而不能根据实际情况任意布线的缺点,提出了一种新型一维微带 PBG(photonic bandgap)单元结构及其等效 L-C 电路模型。本文提出的 PBG 传输线可以应用于微波集成电路中,能够减小电路尺寸,且可以抑制高次谐波的产生。