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Optimal design of third‐order microstrip bandpass filters by direct synthesis technique (DST) 下载免费PDF全文
Fei Xiao Huarong Gong Yong Zhang 《International Journal of Circuit Theory and Applications》2018,46(10):1827-1837
To design microstrip filters is not easy for the sake of their distributed‐element effect. Undoubtedly, to understand their physical mechanism is very important to their design. In this paper, one effective approach to design some third‐order microstrip bandpass filters with each of 2 transmission zeros at each side of the passband is discussed. Lumped‐element equivalent circuits are used to represent these microstrip filters. Then, these lumped‐element equivalent circuits can be synthesized by direct synthesis technique we recently proposed, so that it is likely to calculate initial structural parameters of these microstrip filters and then facilitate their design. Verified by the measured results of the filter designed through the approach in this paper, the performance of the filters is close to ideal frequency responses. Furthermore, another third‐order microstrip bandpass filter is presented, in which open‐circuited stubs at input/output ports are introduced to suppress one specified harmonic to improve out‐of‐band attenuation. 相似文献
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Kari Jokela 《International Journal of Circuit Theory and Applications》1979,7(4):445-461
A design method is described to realize narrow-band stripline or microstrip bandpass filters having one transmission zero near to the upper and lower bandedge. The filters utilize capacitively coupled open half-wave TEM-line resonators. Two nonadjacent resonators are also inductively coupled. No short circuits are needed. The design is based on the approximate or exact synthesis of the lowpass protoype presented by Levy. The transmission line parameters are obtained easily from the design formulae which have been derived using the susceptance (or reactance) slope parameter technique. The filter performance is good up to 12 per cent bandwidth. Measured results show good agreement with the theoretical ones. 相似文献
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基于ADS的一种高指标带通滤波器设计 总被引:1,自引:0,他引:1
介绍了平行耦合线微带带通滤波器的基本原理,提供了一种基于ADS软件设计高指标平行耦合线微带带通滤波器的实例和详细设计步骤,并给出了仿真结果以及ADS优化步骤和原则. 相似文献
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Fei Xiao 《International Journal of Circuit Theory and Applications》2018,46(3):415-426
In radio frequency/microwave or even higher frequency range, various transmission‐line filters have been proposed for frequency selection. Specifically, there is a kind of transmission‐line filters not having source/load inverters. To design them is somewhat difficult, if their physical mechanism is not fully understood. In this paper, the concept of the distributed‐ to lumped‐element equivalence is applied in the synthesis of several microstrip band‐pass filters without source/load inverters. As demonstrated, it can help to reveal the physical mechanism of the filters such as how the resonances are created and coupled. In addition, the distributed‐ to lumped‐element equivalence relations between filter specifications and structural parameters are presented and good initial dimensions are calculated, which will facilitate filter design. Several examples are presented for demonstration. 相似文献
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Pragnan Chakravorty Durbadal Mandal 《International Journal of Numerical Modelling》2016,29(3):520-529
Bandpass filters with wide pass‐band are an essential requirement in various equipments of satellite and defence communication sectors. Here a method of split‐path interactions is proposed to approximately predict the resonant frequency and topology of bandpass filters which otherwise fall under the category of heuristic designs. Curved transmission lines are often required to make filter structures physically compact; however, curvature effects create errors in the theoretical (design) prediction of resonant or central frequencies for bandpass filter design. Earlier propositions on curvature corrections had been considerably precise, but recent design standards demand even higher accuracies. The prime feature of this work is the use of a meta‐heuristic optimization (i.e. Particle Swarm Optimization) technique in curvature corrections for the first time which brings accuracies of over 99% in the corrected results. The split paths used in this design are suitably curved, with the proposed optimized curvature correction technique, so as to attain a compact size of the filter. The resulting filter has a low insertion loss of around −1.00 dB and a sharp stopband cut‐off. Fabrication was done on a FR4 microstrip substrate with a good agreement between measured and simulated results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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针对现代无线通信系统中平坦带通滤波器的需求,提出了一种并联负载的发夹型谐振器,并利用提出的谐振器构建了四阶平坦带通滤波器。首先,通过在发夹型谐振器磁场最强的位置(中心位置)设置电阻,设计了一种新的并联型谐振器,从而可以通过改变电阻值来灵活地调整固有品质因数;其次,采用具有高、低固有品质因数的耦合拓扑来构建四阶平坦带通滤波器。最后,在印刷电路板上制备了一个具有传输零点和平坦带通的四阶带通滤波器。实验结果表明,该四阶带通滤波器的实测结果与仿真结果吻合较好,与其他多阶带通滤波器相比,该四阶带通滤波器具有可灵活控制的固有品质因数和小于0.2dB通带平坦度。 相似文献
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This article describes a class of recently developed multiple-mode-resonator-based bandpass filters for ultra-wide-band (UWB) transmission systems. These filters have many attractive features, including a simple design, compact size, low loss and good linearity in the UWB, enhanced out-of-band rejection, and easy integration with other circuits/antennas. In this article, we present a variety of multiple-mode resonators with stepped-impedance or stub-loaded nonuniform configurations and analyze their properties based on the transmission line theory. Along with the frequency dispersion of parallel-coupled transmission lines, we design and implement various filter structures on planar, uniplanar, and hybrid transmission line geometries. 相似文献
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Xiaolong Zhong Kenneth K. Mei Yaowu Liu 《International Journal of Numerical Modelling》2003,16(4):337-344
A new numerical model of microstrip transmission line circuits in terms of distributed circuit parameters is here illustrated. Based on full‐wave electromagnetic results, the extraction methods of these distributed circuit parameters on different types of microstrip transmission line circuits are introduced. As a preparatory experiment, an improved CAD method using this model is tested on microstrip low‐pass filter. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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耦合微带线参差谐振带通滤波电路 总被引:3,自引:0,他引:3
对于微波集成振荡器或放大器输出端的滤波器,要求具有较好的抑制谐波性能,本文提出耦合微带线参差谐振带通滤波电路,它由半波长谐振器式平行耦合微带线单元电路与传输线段联构成,其特点是有利于对谐波输出的抑制。 相似文献
14.
Tamasi Moyra 《Journal of Computational Electronics》2013,12(2):287-296
In this present work a novel concept for designing of tunable bandpass filter has been introduced with the help of end coupled microstrip transmission line, defected ground structure (DGS) and defected microstrip structure (DMS). Utilizing this concept, one bandpass filter of 8 GHz center frequency with 30 % fractional bandwidth (FBW) at ?3 dB has been implemented for the applications of X-band communication systems. The structure has been simulated with Method of Moment (MoM) based IE3D EM simulator and Measured with Agilent make vector network analyzer of model N5230A. Finally, the simulated result and measurement result provides good agreement between them. 相似文献
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Samaneh Sedighi Maragheh Massoud Dousti Mehdi Dolatshahi Behbod Ghalamkari 《International Journal of Circuit Theory and Applications》2019,47(4):561-571
This paper presents a dual-mode tunable bandpass filter (BPF) for global system for mobile communication, universal mobile telecommunications system, wireless fidelity, and worldwide interoperability for microwave access standard applications. The proposed filter consists of a stepped-impedance resonator, single resonator, and coupled line, which are loaded with varactors. The center frequency and bandwidth of the proposed filter can be tuned with tuning varactors. Furthermore, the measurement results show that the BPF can be tuned over the frequency range of 1.8 to 2.5 GHz. Moreover, the bandwidth can be changed at each certain frequency. Furthermore, using PIN diodes, a bandstop filter is added to the tunable BPF to reduce the out-of-band frequencies around the desired frequencies. The values of LC equivalent circuits are calculated, and the results are compared with those obtained from the layout of the proposed structure. Finally, the measurement results justify the simulation results. 相似文献
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Erkan Yuce Shahram Minaei Oguzhan Cicekoglu 《Electrical Engineering (Archiv fur Elektrotechnik)》2006,88(6):519-525
In this paper, new floating immittance function simulators employing second-generation current controlled conveyors are proposed.
The first four of the presented circuits employ only a single grounded capacitor as passive component and can realize either
a negative or a positive floating inductor or capacitor. The last two of the proposed circuits do not employ passive components
and can realize either negative or positive floating resistances. All of the proposed circuits do not require passive element
matching. As an application, a third-order butterworth filter is realized using the proposed positive floating inductance
simulator. SPICE simulation results and large signal behavior of the filter are included. 相似文献
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本文提出了一种新型缺陷接地结构(DGS),即非周期C型结构,采用仿真分析和实验测试相结合的方法分析了其滤波特性,并对哑铃型和C型两种结构的周期性DGS与非周期性DGS的滤波特性进行了分析比较,结果表明,新型结构在实现双频禁带抑制技术中具有广泛的应用前景。 相似文献
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根据基片集成波导(substrate integrated waveguide,SIW)和传统矩形波导的等效关系,设计了一款基于SIW结构小型化的宽带四路滤波等功分器.通过同轴线在波导中心馈电,输出端口采用微带输出的方式,且输出等幅同相.四排金属孔将波导平均分成4个腔,腔体中同时存在3种模式(TE101/TE102/TE201),实现三模带通;利用感性孔的微扰抑制高次模(TE202),提高阻带性能.实测工作带宽不小于2.5 GHz,中心频率10 GHz.该四路滤波功分器具有体积小、制作简单、方便与其他电路集成等优势. 相似文献
19.
Fei Xiao 《International Journal of Circuit Theory and Applications》2019,47(1):133-151
A power divider is ideally a lossless reciprocal device performing vector summation of two or more input signals, which is an extremely important circuit component in wireless communication systems or radar systems. In this paper, a general concept of lumped-element power divider is discussed. Then, a semi-analytical synthesis technique is presented. General odd-mode and even-mode analysis method is proposed for multi-port symmetrical network and applied in the analysis of N-way lumped-element power dividers. The transmission networks and the matching networks can be synthesized step by step, which greatly simplify their analysis. The transmission networks can be synthesized by those well-known synthesis techniques for two-port networks, and thus the transmission property of power dividers can be accurately controlled. The matching networks are determined by optimization to ensure certain isolation between the output ports. The design procedure is simple and accurate. Apart from the capability of power division, power dividers are also able to play the role of impedance transform and signal processing. Some examples of power dividers with filtering capability are presented for demonstration. In this paper, a general concept of lumped-element power divider is discussed. Then, a semi-analytical synthesis technique is presented. General odd-mode and even-mode analysis method is proposed for multi-port symmetrical network and applied in the analysis of N-way lumped-element power dividers. Transmission networks and matching networks can be synthesized step by step, which greatly simplify their analysis. Apart from the capability of power division, power dividers are also able to play the role of impedance transform and signal processing. 相似文献