共查询到20条相似文献,搜索用时 15 毫秒
1.
《Microwave Theory and Techniques》2008,56(9):2095-2100
2.
《Microwave Theory and Techniques》2006,54(9):3543-3549
The design and implementation of novel coplanar-waveguide (CPW) bandpass and dual-passband filters that consist of the composite right/left-handed short-circuited stubs are proposed. In contrast to the conventional short-circuited stub, whose input impedance repeats every half-wavelength, the composite right/left-handed CPW stub combines the phase-lead composite right/left-handed CPW and the phase-lag uniform CPW to achieve the arbitrary resonant frequencies with compact size. The equivalent bandpass and dual-passband LC resonators are established by investigating the frequency responses of the composite right/left-handed CPW stubs. The composite right/left-handed CPW bandpass filter is 62.5% more compact than the conventional quarter-wavelength shunt-stub CPW bandpass filter. The composite right/left-handed CPW dual-passband filter, which possesses the sharp rejection between the two asymmetric passbands, is also developed. The synthesis procedures of the composite right/left-handed CPW bandpass and dual-passband filters are successfully validated by measurement and full-wave simulation. 相似文献
3.
Sedigheh Alidoost Changiz Ghobadi Javad Nourinia Golzar Eydi 《Wireless Personal Communications》2013,71(3):2147-2160
This paper develops a novel ultra-wideband bandpass filter with high selectivity, deep stop band and compact size. By linking a broadband bandstop filter at two sides with two feed lines via interdigital coupled lines with enhanced coupling degree, an initial ultra-wideband bandpass filter is created. In this filter, all undesired pass bands are rejected by broadband bandstop filter embedded in middle of ultra-wideband filter. Then, stepped impedance open stubs are used for realizing transmission zeros in pass band edges to increase selectivity. Finally, a neuro-genetic method is applied for optimizing of proposed ultra-wideband bandpass filter. For this task, first a nonlinear relation is established between the input (layout parameters) and output (electrical responses) data by using neural network. Then, genetic algorithm is used in conjunction with neural network model for optimizing the ultra-wideband bandpass filter parameters. The designed filter was fabricated and measured that showed good characteristics including deep stop band and very high pass band selectivity. 相似文献
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5.
《Microwave Theory and Techniques》2006,54(10):3746-3750
Novel quasi-elliptic coupled-resonator bandpass filters with wider fractional bandwidth are proposed. By using the broadside-coupled mechanism to couple the half-wavelength microstrip resonators and the quarter-wavelength coplanar-waveguide (CPW) resonators together with introducing two CPW shorted stubs, the required mixed and magnetic couplings associated with the resonators may be enhanced so that a wider bandwidth cross-coupled filter may be realized. Specifically, a fourth-order quasi-elliptic broadside-coupled bandpass filter with a center frequency at$f _0 =1.48~hboxGHz$ , a minimum insertion loss of 0.68 dB, and a wider 3-dB fractional bandwidth of 34.6% is implemented, and its stopband is extended up to 6 GHz$(4f _0)$ with a rejection better than 20 dB. 相似文献
6.
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
7.
A novel ultra wideband (UWB) bandpass filter is presented, using a compact coupled microstrip/coplanar waveguide (CPW) structure. The filter comprises of a single CPW quarter-wavelength resonator which is coupled to two microstrip open-circuited stubs on the other side of a common substrate. The two microstrip open-circuited stubs, which are about a quarter-wavelength long at the center frequency, can function as two resonators with associated coupling arrangement to the CPW. This forms a very compact three-pole filter. The proposed filter also exhibits a quasi-elliptic function response, with one finite-frequency transmission zero closer to each side of the passband. Thus, a high selectivity is achieved using a small number of resonators, which leads to low insertion loss and group delay across the passband. The performance is predicated using EM simulations and verified experimentally. The experimental filter shows a fractional bandwidth of 90% at a center frequency of 6.4GHz, with two observable transmission zeros (attenuation poles) at 1.95 and 10.36GHz, respectively. Furthermore, it has a very small size only amounting to 0.25 by 0.08 guided wavelength at the center frequency 相似文献
8.
This study presents a compact coplanar-waveguide (CPW) parallel-coupled bandpass filter (BPF) with good selectivity and stopband rejection. The inductive terminations are introduced to the conventional anti-parallel coupled-lines, and lumped-element J-inverters are employed, to achieve both size reduction and spurious suppression. Additionally, the inductive cross-coupling effect is introduced to obtain two transmission zeros to enhance the selectivity. Suitable equivalent-circuit model is also established as effective design tool. Specifically, this work demonstrates a compact cross-coupled fourth-order BPF in grounded-CPW configuration. Compared to the conventional filters, the proposed filters exhibit over 65% size reduction, improved selectivity, and wider stopbands up to four times the center frequency 相似文献
9.
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
10.
Yu-Kang Kuo Chi-Hsueh Wang Chun Hsiung Chen 《Microwave and Wireless Components Letters, IEEE》2001,11(2):65-67
Two novel reduced-size coplanar-waveguide (CPW) bandpass filters are proposed. Specifically, the bended short-end parallel stubs together with the folded open-end series stubs are utilized to design a broadband filter, and the slow-wave structures are adopted to implement a narrowband filter. In this study, the proposed filters are examined, theoretically and experimentally 相似文献
11.
In this paper, a new method for designing stubs loaded SIR filter is presented. We can calculate the reflection coefficient of stubs loaded resonator directly by converting the admittance to input terminal. This method replaces the transmission matrix and even-mode and odd-mode analysis. Then, genetic algorithm (GA) is applied to search the corresponding electrical parameters, which provides a more effective and intuitive way to design filters. Then, an ultra-wideband bandpass filter using short-stub loaded SIR is realized, which exhibits a good frequency selectivity from 3.1 GHz to 10.4 GHz. In addition, by applying this method, a dual-passband filter with short and open stubs is achieved. It contains two wide bands at 2 GHz and 5.8 GHz, which concerns the frequencies of GPS and WLAN. Meanwhile, the sizes of these filters are further minimized by bend structure. Finally, the filters are manufactured. As a result, the measured results are in good agreement with the calculated ones. These filters exhibit great frequency-selection characteristics: flat passbands and extremely sharp rejections around the passband. So, based on the verifications of the manufactured filters, this method can be widely used in microwave filter design field. 相似文献
12.
Shum K. M. Luk W. T. Chan C. H. Xue Q. 《Microwave and Wireless Components Letters, IEEE》2007,17(1):43-45
A compact bandpass filter is proposed for lower-band ultra-wideband applications. It entails the design concept of a stub-tapped half-wavelength line resonator which provides three transmission poles in the passband and two transmission zeros at the high and low rejection bands. The two stubs are replaced by a single dual-band stub and the parallel coupled-line structures are meandered, leading to a compact size of 0.26lambdag by 0.32lambda g 相似文献
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14.
Quasi-static design technique for MM-wave micromachined filterswith lumped elements and series stubs
This paper describes micromachined, membrane-supported low-pass and bandpass filters which are suitable for microwave and millimeter-wave (MM-wave) application. The designs are realized in coplanar-waveguide (CPW) form using short- and open-end series stubs with integrated metal-insulator-metal (MIM) capacitors, and are compact in lateral and longitudinal dimensions. A computationally efficient analysis has been developed for the design and characterization of the filters. The technique is based on a quasi-static coupled-line (CL) treatment of the series stubs, and uses normal mode impedance parameters, which are calculated with the spectral-domain approach (SDA). Due to the broad TEM-bandwidth of the membrane-supported transmission lines, the method can accurately predict filter responses well into the rejection band. To demonstrate the above claims, the measured and simulated S-parameters of a 0.3 mm ×2.2 mm low-pass filter with a cutoff frequency at 17 GHz, and a second passband at 115 GHz, are presented. The new approach is also used in the design of bandpass filters which exhibit 1.5-2-dB insertion loss and bandwidths around 10% 相似文献
15.
Yo-Shen Lin Wei-Chih Ku Chi-Hsueh Wang Chun Hsiung Chen 《Microwave and Wireless Components Letters, IEEE》2004,14(9):422-424
Wideband coplanar-waveguide (CPW) bandpass filters based on the cascade of CPW lowpass and highpass periodic structures are proposed. The upper and lower stopband characteristics of proposed bandpass filter can be easily designed by separately adjusting the lowpass and highpass sections, respectively. Specifically, two wideband CPW bandpass filters with sharp roll-off at passband edges and good stopband rejection are demonstrated. 相似文献
16.
In this paper, a novel bandpass filter is presented, designed, and implemented by using a triple mode semi-hexagonal Half-Mode Substrate Integrated Waveguide (HMSIW) cavity, which has the advantages of compact size, low insertion loss, and high selectivity in upper and lower passband. To realize a triple mode filter, the first resonant mode is shifted to near the next two modes using a via hole perturbation. Two microstrip open stubs connected to open edge of HMSIW resonator are introduced to generate two transmission zeros in the lower passband. The position of transmission zeros could be controlled by adjusting the coupling gap between the microstrip open stub resonators. By etching an E-shape slot on the top plate of HMSIW resonator, two other transmission zeros are produced in the upper passband. A wide-band planar six-pole bandpass filter, which has the advantages of wide bandwidth and small size, is also proposed and fabricated by cascading two triple mode resonators. Measured results indicate that 29% and 47% fractional bandwidth, as well as approximately 1 dB and 1.1 dB insertion loss, are achieved for the proposed filters. Measured results of all those filters agree well with the simulated results. 相似文献
17.
The research paper proposes a compact dual notched band ultra-wideband (UWB) bandpass filter (BPF). The basic architecture of the filter is developed using the hybrid microstrip-to-coplanar waveguide (CPW) technology, wherein a short circuited CPW in ground is coupled vertically via the dielectric to the microstrip lines on the top plane. The broadside alignment generates a three pole BPF with dual transmission zeros (TZs) on either passband/stopband edges which leads to minimum insertion loss passband and sharp roll-offs. Later, multiple spirals and split ring resonators (SRRs) are embedded in the CPW of the UWB filter to introduce the dual notches and widen the stopband respectively. The proposed filter is fabricated to justify its measured response. The proposed filter measures only 14.6 × 7.3 mm2. 相似文献
18.
Chi-Feng Chen Ting-Yi Huang Chi-Ping Chou Ruey-Beei Wu 《Microwave Theory and Techniques》2006,54(5):1945-1952
High isolation and compact size microstrip diplexers designed with common resonator sections have been proposed. By exploiting the variable frequency response of the stepped-impedance resonator, resonators can be shared by the two filter channels of the desired diplexer if their fundamental and the first spurious resonant frequency are properly assigned. Size reduction are, therefore, achieved by introducing a few common resonator sections in the circuit. This concept has been verified by the experimental results of two diplexer circuits. One of the diplexers is composed of two three-pole parallel-coupled bandpass filters and the other is composed of two four-pole cross-coupled bandpass filters, which are formed by only five and six resonators, respectively. Both of them occupy extremely small areas while still keeping good isolations. Good agreements are also achieved between measurement and simulation. 相似文献
19.
A novel and compact dual-band filter using a microstrip/coplanar waveguide (CPW) composite structure is proposed. At the bottom of the substrate material, two CPW open-circuited resonators are broadside-coupled to the top microstrip open-circuited stubs. The proposed filter was designed, fabricated and measured. The obtained frequency responses demonstrated that the filter has good dual-band property. 相似文献
20.
Mostafa Danaeian Esmail Zarezadeh Hossein Ghayoumi-Zadeh 《Analog Integrated Circuits and Signal Processing》2018,94(3):469-479
In this paper, a novel compact microstrip dual-band (DB) bandpass filter with high selectivity for wireless local area networks applications is proposed. The design procedure is based on unbalanced composite right/left-handed (UCRLH) transmission lines (TLs). The DB features can be achieved by unbalancing the CRLH transmission line. The necessary conditions to obtain a discontinuous transition between the left- and right-handed bands, intended to provide UCRLLH TL, are investigated. The application of this technique to design of compact DB filters is illustrated. The structure of the proposed DB filter is implemented by a series interdigital capacitor located between two microstrip lines that shorted to the ground plane by vias. The vias with microstrip lines acting as a shunt connected inductor while the series capacitor is realized by interdigital capacitor. The design procedure based on a simple equivalent circuit is also introduced. The proposed filter has advantages such as compact size, easy fabrication, high selectivity, low insertion loss, high return loss and, design flexibility. To validate the proposed technique, the proposed DB filter has been fabricated and tested. Good agreement has been found between simulation and measurement results. The total size of the proposed UCRLH DB filter is 0.17 λg × 0.048 λg, where λg is the guided wavelength of the lower pass-band. The size of the proposed DB filter is more compact in comparison with known similar filters. 相似文献