基于树状分形结构的半模基片集成波导带通滤波器

提出了一种基于分形结构的半模基片集成波导(HMSIW)滤波器。该设计将树状分形结构蚀刻在HMSIW的上金属表面,通过在其高频端引入宽阻带来产生带通效应。这种基于树状分形的HMSIW带通滤波器结构,随着迭代次数的增加,其相对带宽基本保持不变(S11<-15dB),但其带通边缘频响斜度变陡,且带外抑制特性不断增强。仿真结果与实验结果基本吻合,较好地验证了设计的可行性和有效性。     

半模基片集成波导带通滤波器的设计

给出了一种新型半模基片集成波导（HMSIW）带通滤波器的设计和实验方案。该设计利用了半模基片集成波导的高通性质与周期性缝隙的带阻性质来产生带通滤波器的效果。设计的滤波器的中心频率在8GHz,带宽在12．5％左右,通带内插入损耗在1dB以下,回波损耗在-15dB以下,同时具有一定的带外抑制和良好的通带和阻带特性。文章最后用Ansoft HFSS软件进行了仿真实验。     

集成宽带折叠半模基片集成波导带通滤波器

 本文提出并设计了一种新型的折叠半模基片集成波导（Folded Half-Mode Substrate Integrated Waveguide: FHMSIW）宽带带通滤波器,并给出了FHMSIW上层金属层槽缝式和中间金属层槽缝式宽带滤波器的仿真和测试结果。相对于半模基片集成波导（Half-Mode Substrate Integrated Waveguide: HMSIW）槽缝式滤波器,由双层PCB制作的FHMSIW槽缝式滤波器的尺寸减小了约一半。同时测试结果和仿真结果表明该宽带滤波器具有损耗小、带外抑制好等特性。     

一种新的高阶全极点运算跨导放大器-C滤波器系统生成方法

提出一种高阶全极点运算跨导放大器-C滤波器系统生成方法，能方便地设计出全极点高通、低通和带通滤波器。该滤波器与MOS工艺兼容，便于单片集成。滤波器设计实例和PSPICE模拟结果表明所提方法是正确的。     

基于半模基片集成波导的新型带通滤波器研究

在半模基片集成波导上嵌入互补开环谐振器结构,设计了一种结构紧凑的新型带通滤波器.该结构允许低于截止频率以下传输正向波,利用具有高通特性的半模基片集成波导和互补开环谐振器组成具有带通特性的滤波器,通过改变互补开环谐振器结构参数,非常容易调节带通滤波器通带频率,利用该特性可以更容易实现任意通带微波滤波器.该滤波器具有体积小巧、损耗低、易制作、方便与其他电路集成等优势.     

基于半模基片集成波导的片上小型化太赫兹滤波器

为了满足片上太赫兹(THz)通信系统的需要,并验证硅锗双极-互补金属氧化物(SiGe BiCMOS)工艺应用于太赫兹无源器件的性能,设计了一款小型化带通滤波器。该滤波器通过在半模基片集成波导(HMSIW)上加载互补开口谐振环(CSRR)来实现小型化和滤波特性。采用商业电磁仿真软件对滤波器结构进行优化,滤波器的最终尺寸为800μm×360μm。仿真结果表明:滤波器中心频率为140 GHz,带宽为5%,最小插入损耗为2.6 dB。低插入损耗和小型化使得该滤波器适用于片上太赫兹通信系统。     

电流模式高阶OTA-C高通滤波器的设计

提出了一种新的电流模式高阶OTA—C高通滤波器的设计方法。由该方法导出的滤波器具有最少的元件．n阶滤波器仅需n个OTAs和n个电容，所有的电容均接地，便于集成且与VLSI工艺兼容。文中给出了6阶滤波器设计实例，PSPICE仿真结果与理论分析相吻合，验证了该设计方法的可行性。     

一种新型的HMSIW宽带带通滤波器

提出一种基于半模基片集成波导和缺陷地结构的新型宽带带通滤波器,将半模基片集成波导的高通特性与改进的哑铃形缺陷地结构的低通特性结合,实现了一种宽带小型化的带通滤波器。仿真与测试结果表明,该滤波器中心频率为5.3 GHz,相对带宽为53%,通带范围内插入损耗小于1.6 dB。该滤波器具有宽带小型化,容易集成等优点。     

一种具有简单微带线/共面波导结构的新型超宽带带通滤波器

本文提出了一种具有简单微带线/共面波导谐振器结构的新型超宽带带通滤波器,滤波器在通带的两侧具有两个传输零点。滤波器的输入、输出微带（开路）线之间具有耦合电容效应,该电容可以用来调整低端传输零点。微带（开路）线各自与共面波导谐振器可以形成两个串联电容,同时共面波导谐振器的一条短路枝节线形成了一个并联电感。微带开路线上的延伸微带枝节尺寸可以用来调整滤波器的上端传输零点。利用HFSS对该滤波器进行了仿真设计,详细的设计过程也一并给出。仿真表明滤波器的3dB带宽可以覆盖UWB的整个波段。     

基于SIW技术的毫米波滤波器研究与设计

为满足无线通信系统中对紧凑型滤波器的需求,提出一种小型化带通滤波器. 该滤波器通过半模基片集成波导与四分之一波长谐振单元的电磁耦合,在高频阻带产生传输零点;通过强磁区域上层金属面开槽线微扰降低了基模谐振频率,在低频阻带产生传输零点. 所设计的滤波器在8.8~12 GHz频段实现了带通效应,相对带宽为30.7%,带内插损小于0.5 dB,回波损耗大于15 dB,同等带宽条件下相较无开槽线结构尺寸减少了10%;利用额外谐振单元在高频阻带增加了传输零点,使大于20 dB的高频阻带带宽达到了4 GHz,实测结果与仿真结果实现了良好的匹配. 该滤波器具有加工简单、小体积、低损耗、易集成等特点,为滤波器件小型化提供了新颖的设计思路.     

Characterization of the Propagation Properties of the Half-Mode Substrate Integrated Waveguide

The propagation properties of the half-mode substrate integrated waveguide (HMSIW) are studied theoretically and experimentally in this paper. Two equivalent models of the HMSIW are introduced. With the first model, equations are derived to approximate the field distribution inside and outside the HMSIW. Using the second model, an approximate closed-form expression is deduced for calculating the equivalent width of an HMSIW that takes into account the effect of the fringing fields. The obtained design formulas are validated by simulations and experiments. Furthermore, the attenuation characteristics of the HMSIW are studied using the multiline method in the frequency range of 20–60 GHz. A numerical investigation is carried out to distinguish between the contributions of the conductive, dielectric, and radiation losses. As a validation, the measured attenuation constant of a fabricated HMSIW prototype is presented and compared with that of a microstrip (MS) line and a substrate integrated waveguide (SIW). The SIW is designed with the same cutoff frequency and fabricated on the same substrate as the HMSIW. The experimental results show that the HMSIW can be less lossy than the MS line and the SIW at frequencies above 40 GHz.      

Substrate Integrated Waveguide Loaded by Complementary Split-Ring Resonators and Its Applications to Miniaturized Waveguide Filters

A substrate integrated waveguide with square complementary split-ring resonators (CSRRs) etched on the waveguide surface is investigated in this paper. The proposed structures allow the implementation of a forward-wave passband propagating below the characteristic cutoff frequency of the waveguide. By changing the orientations of the CSRRs, which are incorporated in the waveguide surface and can be interpreted in terms of electric dipoles, varied passband characteristics are observed. A detailed explanation for the generation and variations of the passbands has been illuminated. The application of this waveguide and CSRR combination technique to the design of miniaturized waveguide bandpass filters characterized by transmission zeros is then illustrated. Filter design methodology is examined. These proposed filters exhibit high selectivity and compact size due to the employment of the subwavelength resonators and an evanescent-wave transmission. By slightly altering the configuration of the CSRRs, we find that the propagation of the TE₁₀ mode can be suppressed and filters with improved selectivity and stopband rejection can be obtained. To verify the presented concept, three different types of filters are fabricated based on the standard printed circuit board process. The measured results are in good agreement with the simulation.     

基于双层扇形基片集成波导的双频平衡滤波器

提出了一种表面刻有一对互补开环谐振器(CSRR)的45°扇形基片集成波导谐振腔(SSIWR),设计并制作了一款结构紧凑且具有高选择性的双层双频平衡带通滤波器.分别利用具有带通特性的CSRR和谐振腔内的TM220模实现了差模双频响应;模式间的耦合以及缺陷地结构(DGS)的引入使得滤波器在通带附近产生4个传输零点,提高了带...     

基于新型互补开环谐振器的带通滤波器

展示了一种新型互补开环谐振器(Complementary Split Ring Resonators,CSRR).文章分析了CSRR的运行机理,研究了环缝的半径、径向间距对带通滤波器性能的影响,将该结构用于一个三阶波导带通滤波器的设计.并采用有限元法对这种结构的传输特性进行了仿真.仿真结果表明,所设计的波导带通滤波器带宽满足指标700 MHz,中心频率10 GHz,插损0.5 dB,具有体积小、性能高的特点.     

半模基片集成波导带通滤波器的设计与实现

简要介绍半模基片集成波导这一新技术,设计了一个中心频率为35GHz,相对带宽为23％的基片集成波导带通滤波器,CST的数值计算结果显示该途径是成功的.     

一种基于CSRR＿CRLH TL的带通滤波器设计

提出一种基于探针加载的互补开口谐振环(CSRR)的复合左右手传输线(CRLH TL)结构。利用CSRR+CRLH结构的谐振特性,并通过延长CRLH耦合缝隙的长度以及增加CSRR中短路探针的数量,在引入传输零点的同时缩小了滤波器的尺寸。经过仿真优化,实现了滤波器宽频带、高选择性和小型化设计。加工了基于该结构的带通滤波器样机,样机整体尺寸为30mm×15mm×1.35mm。测试结果表明,滤波器的中心频率及插入损耗分别为6.6GHz和0.65dB,3 dB带宽为9.3 GHz,在无线通信、导航等微波系统中具有良好的应用前景。     

CSRR微带线的等效电路模型研究

首先借助三维全波电磁仿真软件HFSS对CSRR微带线进行了仿真,并引入慢波因子（SWF）分析了其慢波特性。然后根据CSRR微带线幅频曲线的单极点低通特性,以一阶巴特沃斯低通滤波器为原型,建立了CSRR微带线的等效电路模型,通过高频电磁仿真结果和电路仿真结果的对比,二者吻合较好,从而验证了该等效电路模型的正确性和有效性。最后,基于该等效电路模型研究了CSRR的结构变化对其电路特性的影响。CSRR微带线必将在未来微带电路设计中具有广泛的应用前景。     

Delay Equalization by Tapered Cutoff Waveguides

When a wave packet propagates in a guided mode subject to cutoff at a definite frequency, dispersion is always present. To restore the shapes of the wave packets at the receiving end, a proper delay equalization must be applied. Waves propagating in a waveguide tapered to cutoff dimensions are reflected mostly in a region where the dimensions are at cutoff. Accordingly waves of higher frequencies will penetrate deeper into the tapered guide and thereby introduce more delay than those of lower frequencies. A profile of a tapered waveguide is obtained for the case of linear delay on the hypothetical assumption that a wave is totally reflected only at the plane of cutoff dimensions. The problem of finding a proper profile is similar in nature to the inverse scattering problem in quantum mechanics. The complex input reflection coefficient introduced by a tapered cutoff waveguide is invariably unity in its magnitude for all frequencies below cutoff and has different phases for different frequencies. Presently available theory for computing the complex reflection coefficient is valid only when its magnitude is smaller than unity. A theoretical method to calculate with accuracy the phase of such unity reflection coefficient is presented. The linking section between the standard waveguide and the tapered cutoff waveguide is designed on the basis of a high-pass filter that introduces no appreciable perturbation to the prescribed delay characteristic. The excellent agreement between the theoretical results and measured data suggests that microwave delay equalizers can be designed "on paper" with "measurement" accuracy without even going to the laboratory. Accordingly the claim can be made that any reasonable amount of delay of simple shape within certain bandwidth limits can be equalized by the present approach.