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该文基于频率变换的方法设计了两种结构的双通带的腔体滤波器,一种是通过谐振器之间直接耦合实现的;另一种是在谐振器之间引入交叉耦合实现的,从而达到产生传输零点的目的。首先根据设计指标,采用频率变换的方法,计算得到谐振器间的耦合系数和外部Q值,然后利用Ansoft HFSS建立同轴腔体滤波器的模型并进行仿真,仿真结果与ADS中等效电路得到的理论结果基本吻合,从而验证了这种方法的正确性。最后通过对级联型结构与交叉耦合型结构双通带腔体滤波器的比较,得出后者比前者具有更好的带外抑制特性。 相似文献
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三等分交叉耦合是一种新型的耦合结构;用其所设计的滤波器具有一些独到优势。本文对L波段微带三等分交叉耦合滤波器进行了理论探讨,给出了其基本物理结构和设计实例.通过利用Ansoft designer软件对设计的滤波器进行仿真,表明了其在高选择性滤波和一些特殊要求滤波应用方面的独到优势。 相似文献
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一种小型的交叉耦合阶梯阻抗谐振器带通滤波器 总被引:1,自引:0,他引:1
利用小型化的阶梯阻抗谐振器设计了一种交叉耦合带通滤波器.引入的交叉耦合结构在带外产生了一对传输零点以更好地抑制带外干扰信号而不影响通带特性.由于采用了小型化的阶梯阻抗谐振器,交叉耦合带通滤波器尺寸大为减小,同时寄生通带移向更高端.实验和仿真结果基本一致. 相似文献
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提出用交指型结构实现超宽带(UWB)带通滤波器的小型化,并给出了设计方法。该结构通过宽边耦合实现超宽带滤波器需要的较大耦合系数,并通过加宽带状线谐振器的宽度减少不必要的交叉耦合,简化了滤波器的设计。最终设计了一个中心频率为f0,相对带宽为58%的六阶交指带通滤波器,滤波器尺寸仅为8 mm×11 mm。从仿真结果看,该滤波器保持了传统交指型滤波器阻带特性好,寄生通带远的优点。 相似文献
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对滤波器交叉耦合技术进行了研究,分析了交叉耦合的矩阵理论,并大致分析了其拓扑结构.从理论上提出了交叉耦合三维拓扑模型,相对于实际应用中的二维拓扑模型,这种结构更为简单,更能充分利用各个耦合腔之间的耦合结构.把交叉耦合结构应用于LC滤波器设计中,计算与仿真结果表明,这种结构可以减少滤波器元器件数目,降低成本,提高性能. 相似文献
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以耦合矩阵综合方法设计的交叉耦合滤波器由于谐振器间耦合系数的色散现象,使滤波器的实际响应与理论综合得到的响应存在差异。针对此情况,首先研究了开环谐振器间电耦合系数随频率的变化趋势及其对交叉耦合滤波器中传输零点位置的影响,随后设计了一种加载于谐振器间的U型微扰结构,通过调节其物理尺寸及位置可以降低耦合系数的色散现象,优化滤波器带外传输零点的分布。基于上述思路,分别设计了传统CQ结构以及加载微扰结构的CQ结构滤波器,其中心频率和通带带宽分别为20.6 GHz和1.4 GHz,加载有微扰结构的滤波器其低频端带外零点相较于传统滤波器从18.6 GHz移动至19.4 GHz,且带内特性和高端传输零点均未受到影响,最终实测结果与仿真结果基本一致。 相似文献
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Compact Bandpass Filters Based on Dual-Plane Microstrip/Coplanar-Waveguide Structure With Quarter-Wavelength Resonators 总被引:1,自引:0,他引:1
Tsung-Nan Kuo Shih-Cheng Lin Chi-Hsueh Wang Chun Hsiung Chen 《Microwave and Wireless Components Letters, IEEE》2007,17(3):178-180
Compact wideband bandpass filters are proposed based on the dual-metal-plane structure consisting of both microstrip and coplanar-waveguide (CPW) quarter-wavelength resonators. By combining the advantages of dual-plane microstrip/CPW structure and stepped-impedance resonators, strong couplings between resonators may be accomplished so that the fourth-order cross-coupled filter with compact size and wide bandwidth may be realized. To further improve the selectivity, the sixth-order cross-coupled filter composed of four microstrip and two CPW resonators is implemented. Specifically, the implemented filters have the merits of compact size, good insertion/return losses, wide fractional bandwidth, and better selectivity. Good agreement between simulated and measured responses of these filters is demonstrated 相似文献
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Chi-Yang Chang Wei-Chen Hsu 《Microwave Theory and Techniques》2002,50(11):2527-2536
This paper presents a novel concept of a square-shaped dielectric-waveguide resonator, which can easily realize a dielectric-waveguide cross-coupled filter or a dielectric-waveguide dual-mode filter, using the conventional printed circuit board (PCB) process. This planar dielectric-waveguide resonator has a higher Q value than a microstrip resonator. The physical mechanisms of both single- and dual-mode filters are elucidated. Some new coupling structures are developed for undergoing the PCB process. Filter design procedures are detailed. Design curves for the coupling coefficients of internal- and external-coupling structures are determined by full-wave finite-element-method electromagnetic calculations. Measurement results are highly consistent with theory for all trial filters. This study offers an effective means of producing low-cost high-performance planar circuit filters. 相似文献
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双模微带三角形贴片滤波器的改进设计 总被引:1,自引:0,他引:1
双模微带谐振器用于微波滤波器设计时具有独特的优点。近年来出现了一些由双模微带三角形贴片谐振器设计的滤波器,这类滤波器结构简单、尺寸小、通带损耗小、功率容限大。在传统的双模微带三角形带通滤波器的基础上,利用分形结构提出一种新型的双模微带三角形带通滤波器,并对此结构的性能进行了分析和研究。实验和测量结果表明,改进后的滤波器在保持原有滤波器性能的基础上,由于引入了分形结构使滤波器的尺寸更加紧凑、有更好的带外抑制能力。仿真和实测结果基本吻合。 相似文献
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Lung-Hwa Hsieh Kai Chang 《Microwave Theory and Techniques》2002,50(7):1795-1800
This paper proposes a new class of slow-wave bandpass filters that uses a microstrip line periodically loaded with microstrip ring or stepped-impedance hairpin resonators. The new slow-wave periodic structures utilize the parallel and series resonance characteristics of the resonators to construct a bandpass filter. Unlike conventional slow-wave filters, the proposed bandpass filters are designed to produce a narrow passband at the fundamental mode of the resonators. The new filters provide lower insertion loss than that of parallel- or cross-coupled ring and stepped-impedance hairpin bandpass filters. The calculated frequency responses of the filters agree well with experiments 相似文献
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This paper presents a method of synthesizing microwave filters consisting of compact microstrip resonators (CMRs). The synthesizing method is based on the conventional insertion-loss design method and can be applied to the design of filters consisting of symmetrical and asymmetrical CMRs. The synthesizing method can help the designer to determine the appropriate layout according to the specified passband and stopband characteristics of the filter. A new type of CMR layout is proposed to suppress the spurious passband response and is applied to the implementation of a Ku-band filter. The measurement of the prototype shows approximately 1.5-dB insertion loss in the passband and a rejection greater than 40 dB at the specified frequencies. Besides, an asymmetrical CMRs filter operated at Ku-band was also designed and fabricated. The measurement result is also close to the computer simulation result. This demonstrates the effectiveness of the proposed design concept 相似文献
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《Microwave Theory and Techniques》2006,54(10):3772-3778
Compact ultra-wideband bandpass filters are proposed based on the composite microstrip–coplanar-waveguide (CPW) structure. In this study, the microstrip–CPW transitions and the CPW shorted stubs are adopted as quasi-lumped-circuit elements for realizing a three-pole high-pass filter prototype. By introducing a cross-coupled capacitance between input and output ports of this high-pass filter and suitably designing the transition stretch stubs, a compact three-pole ultra-wideband bandpass filter is implemented with two transmission zeros located close to the passband edges. To further improve the selectivity, two microstrip shorted stubs are added to implement a five-pole ultra-wideband bandpass filter with good out-of-band response. Being developed from the quasi-lumped elements, and not from the transmission lines, the proposed ultra-wideband filters have sizes more compact than those of the published wideband filters. The proposed ultra-wideband filters have the merits of compact size, flat group delay, good insertion/return loss, and good selectivity. Agreement between simulated and measured responses of these filters is demonstrated. 相似文献
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Cross-coupled microstrip hairpin-resonator filters 总被引:6,自引:0,他引:6
A new class of cross-coupled planar microwave filters using microstrip hairpin resonators is introduced. The realization of bath the canonical and the cascaded quadruplet (CQ) filters is feasible. Coupling characteristics of four basic coupling structures encountered in this class of filters are investigated in the light of full-wave electromagnetic (EM) simulations. A four-pole cross-coupled filter of this type is designed and fabricated. Both the theoretical and experimental performance is presented 相似文献
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A new design of cross-coupled band reject filters in microstrip technology is presented. In the proposed model, the source and the load are not directly coupled. Instead, non-resonating nodes (NRNs) are introduced in the network to generate the required number of attenuation poles and modularize the design. Higher order band reject filters are designed by cascading lower-order building blocks with NRNs inserted between them. A fourth order filter is designed, built and measured. Good agreement between theory and measurement is achieved. 相似文献
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A technique to reduce the size of planar resonators is investigated using a transmission line model and a finite-difference time-domain (FDTD) method. New miniaturized square microstrip resonators are proposed for 900 MHz band. The resonators offer low impedance sections leading to a better handling of power. The feasibility of compact filters using the proposed resonators is demonstrated. The input/output coupling lines of a two-pole filter have been positioned in a way that produces a filter response with transmission zeros on the both sides of the pass-band. Sharper skirts and higher out-of-band rejection are obtained for four-pole filters with cross-coupled resonators. 相似文献
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论述了用Ansoft公司的Designer微波设计软件设计一种改良型的微带交指型带通滤波器。描述了微带交指型滤波器的设计方法,通过实例对这种改良型的微带交指带通滤波器进行了计算机最优化仿真设计,并给出了优化结果。微带交指型滤波器结构紧凑、指标优良,是微波混合集成电路中常见的形式,原理上是由1/4波长平行耦合线滤波器的谐振器折叠而成。 相似文献