波导H-T纵向双缝耦合器的矩量法分析

提出一种波导H-T双缝耦合器,并用矩量法对其进行了分析计算,结果表明这种耦合器反射系数小、耦合度频响特性好,优于单缝耦合器。     

波导H-T纵向双缝耦合器的研究

提出一种波导H－T双缝耦合器,并用矩量法对其进行了分析计算、结果表明这种耦合器反射系数小、耦合度频响特性好,优于单缝耦合器。     

波导H—T纵向双缝耦合器的矩量法分析

提出一种波导H－T双缝耦合器,并用矩量法对其进行了分析计算,结果表明这种耦合器反射系数小、耦合度频响特性好,优于单缝耦合器。     

矩形波导宽壁复合缝隙耦合器的MPSTD算法分析

本文首先研究了多区域时域伪谱(MPSTD)算法应用于波导问题分析时的时域激励源设置方法。然后在此基础上,将MPSTD算法应用于矩形波导宽壁复合缝隙耦合器的分析。针对X波段半高波导,得出了耦合缝隙在不同高度、不同偏置和不同倾斜角度下的谐振长度和散射参量特性。仿真结果表明,将MPSTD算法应用于波导缝隙耦合器的分析,具有较高的计算效率和计算精度。同时该问题的MPSTD分析也拓展了MPSTD算法的应用领域,为准确、快速分析复杂波导问题的宽频时域特性提供了一种思路。     

基于DMRC结构的小型分支线耦合器设计

首先基于复合左右手传输线和微带缺陷结构提出了一种新型双螺旋微带缺陷谐振单元,并研究了其幅度特性和相位特性。然后,研究了其结构参数对传输特性的影响。最后,运用该新型双螺旋微带缺陷结构设计了一个小型化分支线耦合器,仿真及实测结果表明：该分支线耦合器不仅实现了62.8%的小型化,而且避免了后向辐射的问题。     

光纤双折射和耦合器偏振性对环形腔的影响

本文应用琼 斯矩阵分析了光纤的线性双折射和耦合器的偏振性对光纤环形腔特性的影响,光纤的线性双白射和耦合器的偏振性使普通单模光纤环形腔带阻输出特性中的谐振峰分裂为两组,相应的谐振频率发生偏移,偏移量正比于双折射的大小和耦合器的偏振参数。两组谐振峰的相对幅度取决于输入偏振态。调整输入偏振态为Ｘ、Ｙ两线偏振态之一时,就仅出现一组谐振峰。环形腔的精细度与光纤的线性双折射无关,但爱耦合器偏振性的影响。     

W波段回旋速调管输入耦合器的优化设计

该文对应用于W波段TE01模回旋速调管的输入耦合器进行了理论分析,初步得到了输入耦合器的结构尺寸,利用3维电磁模拟软件CST,HFSS与FEKO对其进行了仿真与优化。研究了耦合孔长、宽和圆柱腔半径对耦合器谐振频率及Q值的影响,并对耦合器内腔工作模式的纯度进行了计算。结果表明,在W波段该耦合器能够激励起TE01模,谐振频率为93.55 GHz,外观品质因数为145,耦合器内腔工作模式纯度达到99%,满足设计要求。     

Ka波段3dB定向耦合器的设计与仿真

定向耦合器广泛地用在现代微波系统中,文中介绍了两种应用在平衡式放大器中的3dB定向耦合器。首先对微带分支线耦合器与波导耦合器进行了理论分析,然后利用电磁仿真软件HFSS,对两种耦合器进行了建模仿真。仿真结果验证了这两种定向耦合器的可实现性,最后比较了两种耦合器的性能,并且总结了各自的特点。     

Ka波段3dB定向耦合器的设计与仿真

定向耦合器广泛地用在现代微波系统中,文中介绍了两种应用在平衡式放大器中的3dB定向耦合器。首先对微带分支线耦合器与波导耦合器进行了理论分析,然后利用电磁仿真软件HFSS,对两种耦合器进行了建模仿真。仿真结果验证了这两种定向耦合器的可实现性,最后比较了两种耦合器的性能,并且总结了各自的特点。     

波导侧窗耦合器的多模分析

本文采用模式匹配法对波导侧窗耦合器进行了多模分析,导出了耦合器的S参数计算公式,给出了几组计算得到的耦合器特性曲线,并对具体的耦合器进行了数值计算,理论结果与实验值吻合较好。     

Analysis of waveguide slot-based structures using wide-band equivalent-circuit model

Analysis of geometrically complicated waveguide-based slotted arrays and filters is performed using a simple equivalent-circuit model. First, the circuit parameters (inductance and capacitance) of a simple waveguide slot-coupler problem are obtained through moment-method (MoM) analysis. The values of the lumped LC elements are virtually constant over the frequency range of interest (the X-band) for specific waveguide and slot dimensions. Based on the equivalent-circuit model of a single slot of two coupled waveguides, more complicated structures are then analyzed, such as slot coupler arrays and slot-based waveguide filters. The scattering parameters of these structures are obtained through circuit analysis, and are verified using the MoM and finite-difference time-domain method. Excellent agreement is observed over a wide band of frequencies and is confirmed by experimental results.     

Design of Multilayered K-Band and Ka-Band Slot-Coupled Microstrip 90° Hybrid Couplers Employing Circular Ring Patch Shapes

Numerical analysis and design of millimeter-wave (mmWave) slot-coupled microstrip 90° hybrid couplers employing circular ring patches, which is operating between 18 and 40 GHz frequency range for K-Band and Ka-Band radar applications, is presented in this paper. The proposed design uses multilayer printed circuit board (PCB) technology that allows having a compact and broad bandwidth coupler. The proposed couplers use broadside coupling between microstrip patches at the top and the bottom layers via an elliptical-shaped slot in the common ground plane (mid-layer). The design uses circular ring shaped broadside coupled patches and an elliptical-shaped slot created in a common ground plane between two identical dielectric substrates. The 3 dB coupler prototype has been fabricated on two 0.127 mm thick Rogers Duroid RT5880 substrates. The circuit occupies the dimensions of less than 5 mm × 5 mm without the extension that is required to insert the connectors. Extensive parametric studies are performed to address the effect of varying the coupler parameters on the coupling values, return losses, isolations, transmission magnitudes and phases through the operational frequency bandwidth. A 3 dB/90° hybrid coupler prototype is fabricated and then tested experimentally using Agilent E8364B PNA Network Analyzer. The simulation and experimental results show a good performance in terms of bandwidth, which covers the entire desired frequency range. In addition, detailed design for different coupling values of the proposed coupler is presented in this paper. The proposed coupler can achieve different coupling values range from 3 up to 9 dB that can be used for switched beam antenna array systems.     

Terahertz Wave Polarization Beam Splitter Using Asymmetrical Coupler

This study has proposed and numerically demonstrated a compact terahertz wave polarization beam splitter. The splitter is built by using a asymmetrical directional coupler consisting of a bend waveguide and a slot bend waveguides and achieves a high extinction ratio of 24.88 dB and 16.55 dB for cross and through ports. The optimal coupling region length is found to be 26 μm. By using such a polarization beam splitter, the size of the terahertz wave system could be reduced significantly. The simulation results show that the designed polarization beam splitter can split TEand TM-polarized terahertz wave into different propagation directions with high efficiency over the terahertz wave frequency range from 9.40 THz to 9.65 THz. The device obtained is readily used for a polarization diversity terahertz wave integrated circuit field, particularly for platforms with slot waveguide.     

Microstrip-Slot Coupler Design-Part I: S-Parameters of Uncompensated and Compensated Couplers

Using the even-odd mode analysis of four-port networks with double symmetry, the scattering parameters of the microstrip-slot coupler are derived from the even- and odd-mode parameters of the coupler cross section. The uncompensated coupler and the coupler compensated by extending the slot fines are treated and design specifications are given covering the compensation slot lines. A comparison with experimental data will be given in Part II.     

Photoelastic optical directional couplers in epitaxial GaAs layers

Photoelastic channel optical waveguides showing strong lateral confinement at ?=1.55 ?m have been fabricated by etching a narrow slot through a Au Schottky contact deposited on an n/n+ GaAs layer. Such structures allow electro-optic directional coupler switches of short coupling length (~2 mm) to be easily realised.     

High-performance quasi-optical GaAs monolithic mixer at 110 GHz

A novel GaAs monolithic integrated circuit mixer has been fabricated which is impedance matched to fundamental waveguide. It consists of a slot coupler, coplanar transmission line, surface-oriented Schottky-barrier diode, and RF bypass capacitor monolithically integrated on the GaAs surface. At 110 GHz, a monolithic mixer module mounted in the end of a waveguide horn has an uncooled double-sideband (DSB) mixer noise temperature of 339 K and conversion loss of 3.8 dB.     

Slot-Line Filters and Couplers

The slot-transmission line on a dielectric substrate has many possible microwave circuit applications. This paper presents experimental data concerning the performance of bandpass and bandstop filters and a hybrid coupler; the work described was performed at S-band frequencies using the single substrate slot line geometry. Also included are theoretical data concerning the slot-line wavelength and characteristic impedance for the case of the slot-line configuration having dielectric material above and below the metsllization, the so-called slot-line "sandwich."     

一种Ka频段宽频带90°电桥

给出了一种结构简单的90°电桥方案,可应用在Ka宽频段卫星通信圆极化馈源系统的接收通路中。这种电桥由2个宽边并列放置的波导通过窄壁耦合构成,采用多级阶梯匹配,不需容性加载调配元件,在ka频段2GHz接收频带内两输出端口相位差90°±0.2°,幅度误差小于0.15dB,回波损耗优于-30dB。已成功应用于一种宽频带Ka段段卫星通信馈源中,馈源系统实测轴比优于0.35dB。     

Characteristics of a longitudinal/transverse coupling slot incrossed rectangular waveguides

A rigorous analysis of a broad-wall slot coupler between two crossed rectangular waveguides is presented. The slot is longitudinal and offset from the center line in the main guide and is centered transverse in the branch guide. Integral equations are developed, taking into account finite wall thickness. The integral equations are then solved for the aperture electric field. Coupling slot characteristics are obtained, including the resonant length and dominant mode scattering. Numerical results for resonant length and scattering parameters are presented over a range of offsets, waveguide dimensions, and frequencies