基于电调谐DOCCII的电流模式连续时间滤波器

本文提出了基于可变电流增益双输出CCII(DOCCII)的电流模式N阶低通滤波器和通用滤波器,并给出了N阶通用滤波器的一个通用表达式。所给出的滤波器参数可以通过DOCCII的可变电流增益因子独立调谐,并且结构简单,所有无源元件均接地,便于集成。     

双频带介质集成波导滤波器的设计

介绍了一种双频带带通滤波器,该滤波器源与负载之间的两条通路用来实现两个频带,且滤波器每条通路的阶数和带宽都可以灵活设计。为了实现小体积且方便与平面电路集成,滤波器用介质集成波导设计,采用折叠排列,用微带馈电。另外在公共端设计金属通孔使两条通路同时达到阻抗匹配,使两条通路互不影响。在X至Ku频段内设计了两个双频带带通滤波器,这两个滤波器的中心频率均为11和13 GHz。设计的带宽为200,380,400和200 MHz。实测结果与仿真曲线较为吻合。     

Design of Dielectric Waveguide Bandpass Filters Using Parallel-Coupled Gratings

Techniques for the design of narrow-band (of the order of a percent or so), bandpass filters using dielectric waveguide gratings are presented. These filters use both single, uncoupled gratings and parallel-coupled configurations of gratings to form multiresonator bandpass filter structures. Transmission-line equivalent circuits are used to model the dielectric waveguide gratings. Using this model, it is then shown how direct-coupled-resonator theory can be applied to such filter structures to synthesize a prescribed passband having Chebyshev or maximally flat characteristic. On the other hand, the parallel-coupled gratings give these filters broad and strong, absorptive stopbands, as is explained. Experimental results are presented which show good agreement between theoretical and measured results.     

Experimental Study of Dielectric Waveguide Y-Junctions for Millimeter-Wave Integrated Circuits

Symmetric and asymmetic Y-junctions have been fabricated from rectangular dielectric image line, and the transmission and reflection characteristics have been measured in the 20-26-GHz range. The tested symmetric Y-junction operates as a near 3-dB power divider for the junction half-angle below ~20°. The maximum allowable junction angle of the symmetric Y-junction is discussed, which is very important for millimeter-wave integrated-circuit applications. It is shown that the asymmetric Y-junction can be used as a directional coupler because of the controllable splitting ratio and high isolation. The results for the asymmetric Y-junction with a gap are also presented.     

Design of Nonradiative Dielectric Waveguide Filters (Short Papers)

An efficient design technique of nonradiative dielectric waveguide filters for use at millimeter wavelengths is developed. Filter stuctures considered here are a gap-coupled type and an altenating-width type. According to present theory, 3-pole, 0.1-dB Chebyshev ripple bandpass filters with a 2-percent bandwidth at a center frequency of 49.5 GHz were designed and fabricated with Teflon dielectric. Calculated and measured filter responses agree quite well, and excess insertion losses are found to be as small as 0.3 dB for both types of the fabricated filter circuits.     

宽范围可调MEMS集成滤波器的设计与制作

基于MEMS平面螺旋电感和MEMS可调平行板电容设计并制作了一种宽可调范围的集成可调带通滤波器。理论分析并计算了可调滤波器电感和可调电容的取值范围,利用HFSS设计得到各元件结构参数,并使用AnsoftDesigner分析软件对可调滤波器电路进行了模拟仿真。设计得到的可调滤波器中心频率调节范围为400～700MHz,可调率达75%,实现了宽范围可调,3dB相对带宽范围为5%～10%,插入损耗小于5dB,芯片尺寸为20mm×6mm×0.4mm。给出了一套基于MEMS平面工艺的MEMS集成可调滤波器的制作流程,实现了MEMS集成可调滤波器的工艺制作及测试。测试结果表明,获得的可调滤波器实现了通带频率宽范围可调。     

Millimeter Wave Substrate Integrated Waveguide Antennas: Design and Fabrication Analysis

The paper presents a new concept in antenna design, whereby a photo-imageable thick-film process is used to integrate a waveguide antenna within a multilayer structure. This has yielded a very compact, high performance antenna working at high millimeter-wave (mm-wave) frequencies, with a high degree of repeatability and reliability in antenna construction. Theoretical and experimental results for 70 GHz mm-wave integrated antennas, fabricated using the new technique, are presented. The antennas were formed from miniature slotted waveguide arrays using up to 18 layers of photo-imageable material. To enhance the electrical performance a novel folded waveguide array was also investigated. The fabrication process is analyzed in detail and the critical issues involved in the fabrication cycle are discussed. The losses in the substrate integrated waveguide have been calculated. The performance of the new integrated antenna is compared to conventional metallic, air-filled waveguide antennas, and also to conventional microstrip antenna arrays operating at the same frequencies.      

Dielectric Resonator Filters for Application in Microwave Integrated Circuits

Design of bandpass filters for microwave integrated circuits (MICS) utilizing dielectric resonators is discussed. Synthesis methods for both Tschebycheff and Butterworth responses are derived. Experimental results with S- and X-band filters are presented, and the agreement between theory and experiments is shown to be fairly good. Limitations on this technique due to poor temperature stability are also discussed.     

液晶调谐滤光片研究

本文报道了选用BL－009和E70两种液晶材料,利用其电光效应研制调谐滤光片的工作。实验结果表明这种滤光片具有调谐电压低、透射比高及调谐范围大等优点。     

Ku波段基片集成波导带通滤波器的设计

设计了一款基于基片集成波导的ku波段卫星通信的带通滤波器。描述了位于SIW内部的金属通孔的等效电路模型,并分析通孔直径、位置等关键参数对滤波器性能的影响。针对基于中心位置的SIW带通滤波器带宽较窄的问题,提出偏置金属通孔SIW带通滤波器的设计方法,从而增大滤波器的带宽。并通过对改进后的基片集成波导带通滤波器的仿真,验证了设计的正确性和方法的有效性。     

基片集成波导双频段可调滤波器设计

根据基片集成波导谐振腔微扰原理,设计了一种基片集成波导双频带可调滤波器。通过在基片集成波导谐振腔中插入不同数量的金属铜柱,对电场进行微扰,实现滤波器四个状态可调。滤波器的第一通带由TE101模谐振产生,第二通带由TE_(102)和TE_(201)模谐振产生。为了验证设计的有效性,对可调滤波器进行加工与测试,实测滤波器的中心频率可以在5.25/8.25 GHz、6.40/8.32 GHz、7.90/8.95 GHz、8.20/9.20 GHz变化,插入损耗为-2.1～-3.8 dB,回波损耗小于-10 dB,满足设计要求。该滤波器具有易调谐、与其他平面电路易集成等优势。     

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.     

Miniaturized Bandpass Filters With Double-Folded Substrate Integrated Waveguide Resonators in LTCC

This paper proposes miniaturized bandpass filters with double-folded substrate integrated waveguide (SIW) resonators using multilayer low-temperature co-fired ceramic (LTCC) technology. Formed by inserting a metal plate with two orthogonal slots into the cavity, the double-folded SIW resonator is used for the circuit size reduction with its footprint about a quarter of the conventional ${rm TE}_{101}$ mode. With LTCC technology, there is more flexibility to organize the cavities of filters because of the 3-D arrangement. The vertically stacked cavities are coupled by “L”- or “U”-shaped slots, and if arranged horizontally, by an inductive window on the common sidewall or a suspended stripline between the cavities. Through experimental measurements and simulations at both the $Ka$- $V$ -bands, it has been demonstrated that the proposed filter has compact sizes and good frequency responses. The area of the fully stacked Chebyshev filter has 88% size reduction in comparison with a three-pole planar waveguide filter, while the vertically stacked quasi-elliptic filter has 74% size reduction in comparison with a four-pole planar waveguide filter.      

Modal Analysis of a Planar Dielectric Strip Waveguide for Millimeter-Wave Integrated Circuits

A novel planar waveguide which is suitable for guiding electromagnetic (EM) energy in the millimeter-wave and submillimeter- wave regions is studied. By using Wiener-Hopf techniques, we first determine the reflection coefficient at the open ends of the guide. Next, a transverse resonance condition is applied to determine the dispersion relation of the modal field. The propagation constant is found to be complex. Its imaginary part accounts for the edge diffraction loss of the strip through the open ends of the guide. Extensive numerical results are given for the disperson characteristics and modal field distributions for silicon and fuzed quartz substrates. The planar strip waveguide should have the advantages of simplicity in processing, a lower random diffraction loss, and accessibility to monolithic integration techniques.     

一种小型化电调功分器设计

该文提出了一种等功分电调功分器。该功分器基于传输线变换技术进行设计,利用变容二极管调节功分器的中心频率,实现了从900～1050MHz的中心频率调节范围,在可调范围内实现S11小于-20dB。S21、S31大于-3．2dB,S23小于-22dB。该功分器具有尺寸小,偏置电路简单的优点。     

一种L波段电调微带滤波器的设计

电调谐预选器是现代无线电监测接收机中的关键部件,在射频前端加入窄带预选器可以改善系统的二阶输入截点,提高系统的抗阻塞干扰能力。介绍了基于微带梳状线可变电容加载型电调谐带通滤波器的设计,分析了其理论设计原理,利用ADS软件对该电调滤波器进行了电路电磁相结合的协同仿真。通过实测,该滤波器可调覆盖范围1.5～2.1 GHz,通带插损小于4 dB。对该滤波器的下一步性能改进做了讨论。     

基于非谐振节点的盒型拓扑结构基片集成波导滤波器设计

针对微波带通滤波器小型化、高性能的应用需求,提出使用单模和双模基片集成波导谐振器相结合设计广义切比雪夫带通滤波器.该结构可实现盒型拓扑结构,并且双模基片集成波导谐振器中的主模TE₁₀₁作为非谐振节点提供一条额外的交叉耦合路径,并能增加一个有限的传输零点;该结构不需要传统负耦合结构就能实现两个有限传输零点,并且该传输零点可以位于通带上方或下方,具有设计灵活的特点.为了进一步提高滤波器的选择性,研究了在四阶滤波器上蚀刻互补开环谐振器设计拓展的盒型拓扑结构滤波器,并实现五阶滤波功能三个有限传输零点.为了验证结构的合理性,设计了两款中心频率为10GHz的对称和非对称响应的四阶滤波器、一款中心频率为5.8GHz的五阶滤波器,并给出相应的含非谐振节点的盒型拓扑结构耦合矩阵进行验证,最后进行加工和测试.耦合矩阵响应、仿真和测试结果一致性较好,表明了该结构设计高性能滤波器的可行性.     

Design of Ultra-Wideband Substrate Integrated Waveguide (SIW) Filters in Zigzag Topology

In this letter we propose a modified substrate integrated waveguide (SIW) zigzag filter topology, which allows the flexible introduction of extra cross-couplings between non adjacent resonators. This novel topology permits to control the location of the transmission zeros, thus improving the resulting filter selectivity. Therefore, it has been used to design filters in compliance with the restrictive ultra-wideband European mask. In order to validate the new proposed topology, two filter prototypes have been designed, manufactured and measured, showing very good agreement with simulation data.      

基于基片集成波导馈电的Ka波段渐变缝隙天线设计

在被动毫米波 (PMMW) 成像焦平面阵列 (FPA) 馈源的天线中,直线渐变缝隙天线 (LTSA) 相对于传统的喇叭天线、介质棒天线具有其独特的优势。该文优化设计了一种新型的对跖直线渐变缝隙天线 (ALTSA),通过加载超材料结构使天线的增益得到了改善,天线采用基片集成波导 (SIW) 技术进行馈电。通过仿真与测试分析,该天线在较宽的频带内具有良好的阻抗特性、较低的副瓣电平及较高且平稳的增益,所设计的天线具有较小的口径宽度,在焦平面中易于组成较为密集的馈源阵列,以提高被动毫米波成像的空间分辨率。