共查询到20条相似文献,搜索用时 15 毫秒
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In this letter, a miniaturized planar two-pole microwave filter with two transmission zeros is presented. The building block of this filter is a high-Q double spiral slot resonator backed by a conductor plane. The provision of a float back conductor plane allows vertical integration of this filter with other passive and active RF electronic components usually found in miniaturized wireless transceivers. The conductor plane also provides a coupling mechanism between the input and output of the filter giving rise to transmission zeros. It is shown that the location of transmission zeros can easily be adjusted and significant out-of-band rejection be achieved using only two miniaturized double-spiral resonators. The design procedure and fabrication of a two-pole filter operating at 2.11GHz is demonstrated and a very good agreement between measured and simulated results is shown 相似文献
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A tunable planar combline filter exhibiting multiple transmission zeros is reported in this letter. By introducing two new coupled lines, the source/load-multiresonator coupling phenomenon is obtained without using additional combline resonators. The transmission zero locations can be adjusted by means of the length of these coupled lines to improve the upper stopband rejection. Moreover, all of these transmission zeros can be tuned at the same time as the passband without distorting the filtering-response shape. Parasitic coupling effects of the proposed filter topology and guidelines for their compensation are also discussed. The described combline filter is experimentally validated with the design and manufacture of a three-stage electronically-tunable prototype with five transmission zeros. 相似文献
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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。 相似文献
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Qing-Xin Chu Huan Wang 《Microwave Theory and Techniques》2008,56(2):431-439
A novel cascaded microstrip open-loop resonator filter with controllable electric and magnetic mixed coupling is presented to have one or more transmission zeros. For two coupled resonators, the coupled sides with the maximum magnetic field are combined with their open gaps with the maximum electric field, creating the electric and magnetic mixed coupling. By adjusting the distances between resonators and the positions of open gaps in a mixed coupled filter, the coupling coefficients can be changed, and controllable transmission zeros can be produced in the lower stopband, upper stopband, or both. Design and fabrication of the proposed second-and fourth-order filters show the advantages: such as a smaller number of resonators, higher rejection level, as well as asymmetrical response; moreover, the location of the transmission zeros can be precisely controlled. 相似文献
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提出了一种用传输线在微带交叉滤波器和腔体交叉滤波器中实现交叉耦合极性改变的新方法。在微带交叉耦合滤波器中运用180°电长度的传输线实现源与非相邻谐振器的耦合,可使交叉耦合极性由容性变为感性。在腔体交叉耦合滤波器中,使用180°左右电长度的传输线,可使传输零点从阻带高端移动到阻带低端。讨论了不同电长度的传输线对交叉耦合的影响,通过调节传输线的电长度,控制传输零点的位置,提高滤波器的带外抑制。这种改变耦合极性的方法,可以用同一耦合方式获得任意位置的传输零点,给滤波器设计提供了更大的自由度。 相似文献
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主要研究微带交叉耦合滤波器的简化设计。通过约束传输零点之间的关系,简化了带通滤波器交差耦合的拓扑结构,同时又较好保持了带通滤波器带外的抑制能力。在利用微带结构实现时,采用了谐振器顺序耦合的结构,降低了滤波器微调的难度。同时在第一和第四谐振器间增加一段传输线以引入交叉耦合,通过调整引入传输线的位置等可调整相应传输零点的位置,增加了滤波器设计的灵活性。仿真结果验证了相关方法的有效性。 相似文献
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Ching-Ku Liao Chi-Yang Chang 《Microwave and Wireless Components Letters, IEEE》2005,15(12):841-843
A microstrip cross-coupled filter with two independently controllable transmission zeros on upper stopband is presented. The initial filter structure is a conventional Chebyshev-response parallel-coupled filter that can be easily realized by the analytical method. The newly proposed coupling/shielding lines can effectively control the cross and main couplings without changing the original filter layout. This approach allows a designer to eliminate the tedious segmentation method, which is usually used to establish the relation between the coupling coefficient and physical distance between resonators. A three-order filter is designed and fabricated for demonstration. 相似文献
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Realization of transmission zeros in combline filters using an auxiliary inductively coupled ground plane 总被引:5,自引:0,他引:5
Ching-Wen Tang Yin-Ching Lin Chi-Yang Chang 《Microwave Theory and Techniques》2003,51(10):2112-2118
The out-band transmission zeros of the multilayer low-temperature co-fired ceramic bandpass filter are studied. The design target of this filter, with passband between 2.3-2.65 GHz (the true application is 2.4-2.483 GHz), is to reject the local oscillator and image signals and, in the mean time, to suppress the harmonic frequency. This filter is a modified three-pole combline filter, which can easily achieve a high rejection rate and low insertion loss. The source-load coupling capacitor incorporation with cross-coupling grounding inductors can generate three transmission zeros. By properly adjusting the inductance values of the inductors between three resonators and ground the transmission zero can easily be manipulated at a high-side skirt to suppress the harmonic frequency. The measured results match well with the electromagnetic simulation that provides evidence for the feasibility of the proposed design. 相似文献
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该文提出了一种具有3个传输零点的高带外抑制小型化带通滤波器。通过耦合控制可在梳状线滤波器响应中引入3个传输零点。通过源/负载耦合和传输线上刻蚀的马刺线可降低带外抑制,使滤波器获得更好的性能。设计并制作了一款小型化带通滤波器实物,仿真结果表明,该文设计的滤波器工作中心频率和相对带宽分别为2.12 GHz和20%,该滤波器的回波损耗优于40 dB,插入损耗小于0.2 dB,带外抑制小于40 dB。此外,该滤波器还具有结构简单紧凑、易加工等特点,实物测试结果与仿真结果基本一致。 相似文献
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Tsung-Nan Kuo Chi-Hsueh Wang Chun Hsiung Chen 《Microwave and Wireless Components Letters, IEEE》2007,17(12):852-854
A compact ultra-wideband (UWB) bandpass filter is proposed based on the coplanar-waveguide (CPW) split-mode resonator. By suitably introducing a short-circuited stub to implement the shunt inductance between two quarter wavelength CPW stepped-impedance resonators, a strong magnetic coupling may be realized so that a CPW split-mode resonator may be constructed. Moreover, by properly designing the dual-metal-plane structure, one may accomplish a microstrip-to-CPW feeding mechanism to provide strong enough capacitive coupling for bandwidth enhancement and also introduce an extra electric coupling between input and output ports so that two transmission zeros may be created for selectivity improvement. The implemented UWB filter shows a fractional bandwidth of 116% and two transmission zeros at 1.705 and 11.39 GHz. Good agreement between simulated and measured responses is observed. 相似文献
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《Microwave and Wireless Components Letters, IEEE》2009,19(11):701-703
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《Microwave Theory and Techniques》2008,56(9):2101-2110
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提出了一种基于单层基片集成波导谐振腔的双通带滤波器。滤波器由传统折叠排列的6个谐振腔组成。通过在通带内设置一对传输零点,将传统滤波器的通带一分为二,实现了双通带。仿真结果表明滤波器的两个通带分别工作于9.85 GHz和10.08 GHz,在相对带宽分别为1.29%和1.76%的通带内,插入损耗小于1.68 dB和1.3 dB,回波损耗大于24 dB和14 dB,通带之间的隔离大于17 dB。该滤波器在无线通讯系统中具有良好的应用前景。 相似文献
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《Microwave and Wireless Components Letters, IEEE》2009,19(2):71-73
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提出一种新型含源-负载耦合的交叉耦合微带带通滤波器,该滤波器的传输特性由分布在介质上下表面的开环谐振器通过引入位于两介质层中间公共地板上的开缝耦舍得到,且将位于顶层的源引入底层,实现了层间源、负载的容性耦合,确保了带外的传输零点,并对源、负载间的耦合进行了等效电路分析。与传统边缘耦合的平面结构滤波器相比,体积减小为原来的一半,且带外抑制良好。三维仿真软件HFSS用来计算该滤波器的耦合系数,并协同Ansoft公司的Designer,通过对参数的提取来迭代优化该滤波器,有效地减少了滤波器的优化时间。对滤波器进行了仿真与实测,其结果表明,实测与理论值、仿真值吻合较好。 相似文献
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A second-order cross-coupled combline filter which has three finite transmission zeros is presented. The problem of the frequency-invariant coupling in a real circuit is introduced. To make extra transmission zeros, a top metalized dielectric block is used. 相似文献
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为了提高滤波器的阻带衰减,研究了源与负载感性交叉耦合的小型介质滤波器。首次提出一种新概念:将源和负载看作准谐振器。以贴片电感作为源与负载之间、源与第二个谐振器之间的交叉耦合元件,两个准谐振器和两个介质谐振器可构成级联四节(CQ),一个准谐振器和两个介质谐振器可构成级联三节(CT)。分析了传输零点的位置,详细讨论了这种滤波器结构的设计方法。采用介电常数为80的介质陶瓷组装了3个两级介质滤波器,并进行测试,结果表明传输零点的个数和位置与仿真设计相符合。滤波器的体积小,均为14 mm×6.5 mm×10 mm。 相似文献
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一种具有传输零点的Hairpin带通滤波器设计 总被引:2,自引:0,他引:2
本文通过在微带(hairpin)滤波器的谐振器上并联微带开路线,构成了一种新的hairpin带通滤波器。该滤波器在通带附近有一对传输零点,具有良好的频率响应以及频率选择特性。由于这种类型的微带滤波器实现传输零点不需要通过滤波器非相邻谐振器间的交叉耦合来获得,因此,设计过程非常简单。 相似文献
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In this article, a novel idea to introduce two coupling paths including one electric coupling and one mixed electric and magnetic coupling between adjacent resonators is proposed. Theoretical exploration based on equivalent circuit model reveals that two adjustable finite transmission zeros can be generated to improve filter performances as the result of the interaction of the two paths for either electric domain or magnetic domain coupling. As an example, a microstrip filter is designed, fabricated and measured using the proposed configuration. The measure results validate and confirm the feasibility of the proposed design methodology. 相似文献