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Impedance Resonators (impedance + resonator)

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Engineering	100%

Selected Abstracts

Compact ultra-wideband bandpass filter using defected ground structures

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2010
J. K. Lee
Abstract In this letter, a compact ultra-wideband (UWB) bandpass filter (BPF) is presented with improved upper stopband performance using six defected ground structures (DGS). The proposed BPF is composed of seven DGSs which are positioned under the input and output microstrip line and coupled double step impedance resonator (CDSIR). By using CDSIR and open loop defected ground structure (OLDGS), we can achieve UWB BPF characteristics, and by using the conventional DGSs under input and output microstrip line, we can improve upper stopband performance. Simulated and measured results are found in good agreement with each other, showing a wide passband from 3.4 to 10.9 GHz, minimum insertion loss of 0.61 dB at 7.02 GHz and the group delay variation is less than 0.4 ns in the operating band while wide upper stopband with more than 30 dB attenuation up to 20 GHz. In addition, the proposed UWB BPF has a compact size. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2173,2175, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25436 [source]

Wideband spurious suppression of dual-mode band-pass filter using defected cascaded resonators

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2010
Hung-Wei Wu
Abstract This article presents a new design of wideband spurious suppression of dual-mode band-pass filter (BPF) using defected cascaded resonators (DCRs). The pattern of the DCRs is similar with that of the conventional low-pass stepped impedance resonator, whereas it is etched in the ground. It is verified that adding DCRs in planar BPF can effectively provide a very wideband range for spurious suppression. The dual-mode BPF is designed at center frequency (f0) of 5.2 GHz, and has a very wideband spurious suppression below 30 dB as far as over 5f0 when using the DCRs. The measured results have a good agreement with the EM simulated results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1694,1697, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25332 [source]

Wideband cross-coupled filter using defected stepped impedance resonator

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2010
Bian Wu
Abstract A novel wideband cross-coupled band-pass filter based on defected stepped impedance resonator (DSIR) is presented in this article. Although the DSIR has opposite impedance characteristic and field distribution to the microstrip SIR, its resonant property is similar to the latter. The internal coupling coefficients of DSIRs are found to be large enough for the wideband filter design. A four-pole, cross-coupled band-pass filter with f0 = 1.6 GHz and FBW = 12% is designed and fabricated using the folded DSIR. Experimental result has good agreement with the simulation. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 558,561, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24972 [source]

A novel dual-band bandpass filter using stepped impedance resonators with transmission zeros

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2008
Qing-Xin Chu
Abstract A novel dual-band bandpass filter using stepped impedance resonator is proposed in this letter. New coupling structures are illustrated to replace the normal counterparts, the circuit size is reduced about 40% compared with the conventional BPF with the same specifications, while the new structure can generate two transmission zeros in the insertion loss response, to validate the design and analysis, two dual-band bandpass filters centered at 2.4 GHz/5.2 GHz and 2.4 GHz/5.7 GHz for WLAN application were fabricated and measured, it is shown that the measured and simulated performance are in good agreement. The bandpass filters achieved insertion loss of less than 2 dB and return loss of greater than 16 dB in each band. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1466,1468, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23394 [source]

Design of compact microstrip diplexer with simple coupled resonators

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2007
Min-Hang Weng
Abstract This article presents a microstrip diplexer with 2.4/5.2 GHz response by using the simple coupled resonators for reducing the circuit size. Stepped impedance resonator (SIR) can be shared by the two filter channels for the designed diplexer if their fundamental and the higher order frequencies are properly assigned. The diplexer has only three simple resonators which can achieve both two good passbands and effectively reduce the circuit size. Measured results of the proposed diplexer have a good agreement with the electromagnetic (EM) simulated results. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1222,1225, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI.10.1002/mop.22397 [source]

The design of a compact quasi-elliptic filter using stepped impedance resonators with harmonic suppression

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2007
Yu-Wei Chen
Abstract A bandpass filter is designed at 2.4 GHz using two end-connected quarter-wavelength stepped impedance resonators. The quarter-wavelength stepped impedance resonators having one end shorted are formed by a half-wavelength stepped impedance resonator with its middle shorting to ground. The modes that the shorted-end ,/4 stepped impedance resonator supports are the (1 + 2n)/4. An enhanced U-shape coupling feed is adopted in the filter design to reduce the insertion losses as well as to suppress the first higher harmonic. A dual-path design is implemented in the proposed filter to create a quasi-elliptic frequency response. The equivalent circuit model is developed and the experiments are conducted for circuit design verification. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 800,804, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22298 [source]

A compact narrow-band microstrip bandpass filter with a complementary split-ring resonator

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2006
Hung-Wei Wu
Abstract This investigation proposes a compact bandpass filter (BPF) using a combination of the coupled uniform impedance resonator (CUIR) and the single complementary split-ring resonator (CSRR). Two transmission zeros of the proposed BPF can be controlled by tuning the dimension of CSRR at higher stopband. As operating at the same frequency, the size of the proposed BPF has a reduction of 26%, compared with the size of the conventional parallel coupled BPF. Measured results of the proposed BPF have good agreement with the electromagnetic simulated results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2103,2106, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21865 [source]

Design of miniature wideband interdigital filters

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 1 2007
Neil Thomson
Abstract In this paper a practical design procedure is suggested for designing wideband miniature interdigital filters. The proposed design approach is based on a concept of parameter mapping between two wideband filters, i.e. a conventional interdigital filter with uniform impedance resonators (UIR) and a desired miniature interdigital filter using stepped impedance resonators (SIR), allowing filter designers to deploy traditional designs with powerful electromagnetic (EM) simulators. For demonstration, a five-pole SIR interdigital filter with a fractional bandwidth (FBW) of 25% has been designed, fabricated, and tested. The demonstrator shows an excellent performance, which matches well to that of its conventional counterpart so as to validate the proposed design procedure. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. [source]

Design of dual-band SIR bandpass filter with a broad upper rejection band for WLANs

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2009
Yu-Chi Chang
Abstract In this letter, we proposed the design of novel dual-band bandpass filter (BPF) with a broad upper rejection band using only two asymmetric stepped impedance resonators (SIRs), which has a smaller circuit size in comparison of previous works. The feature of the asymmetric SIR is only one-step discontinuity, which is different from the conventional SIR with two-step discontinuities. By selecting properly the impedance ratio (R) and physical length ratio (,) of the proposed asymmetric SIRs, the low loss dual-band BPF centered at 2.4/5.2 GHz with a wide upper rejection band from 6 to 14 GHz can be implemented perfectly. The bandwidths and the coupling coefficients of the two passbands can be tunable by adjusting the coupling gap distance between the resonators, which are calculated by using full-wave simulator IE3D. Good agreement between the electromagnetic (EM) simulation and measurement is reported. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1143,1146, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24227 [source]

Compact dual-band filter design using crossly coupled ,/4 SIRs embedded with spur-line for WLAN applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2008
Pow-Wen Chen
Abstract This article presents a compact dual-band bandpass filter (BPF) design using ,/4 stepped impedance resonators (SIRs) embedded with spur-line for the WLAN applications. The filter covers both the operating frequencies of 2.45 GHz and 5.2,5.8 GHz. The crossly coupled mechanism is used in the filter design to provide attenuation poles by the passband edges for enhancing the signal selectivity and increasing stopband rejection levels. The tapped-line is incorporated in feed structure to save the circuit space. The spur-line is embedded in each I/O SIRs to push the upper stopband limit to a higher frequency. Experiments are conducted to verify the circuit performance. A good agreement is observed between the simulation and the measurement. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2807,2810, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23846 [source]

Synthesis of ultrawideband bandpass filter by multisection of commensurate stepped-impedance resonators

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2008
Chun-Ping Chen
Abstract A novel filter prototype composed of multisection of stepped impedance resonators (SIRs) is proposed to realize the ultra-wideband bandpass (UWB) filter. The relation between the modes number and stage number of resonators is first discussed, followed by the derivation of the corresponding Chebyshev filtering function. Furthermore, the equivalent circuit model of this new filter prototype is established based on the transmission-line theory for filter synthesis. As an example, a FCC UWB filter is synthesized with the proposed filter prototype to possess a passband from 3.1 to 10.6 GHz (fractional bandwidth is about 110%). The synthesized circuit model are further optimized by EM simulator, fabricated in microstrip line, and characterized by network analyzer. The good agreement between the measured and predicted frequency responses validates the effectiveness of newly proposed synthesis approach. In addition, the designed filter exhibits good characteristics of comparatively low insertion loss, quite sharp skirts, very flat group delay, and good stopband (especially in lower one) as well. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2635,2639, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23756 [source]

A novel dual-band bandpass filter using stepped impedance resonators with transmission zeros

Design of the wideband dual-mode bandpass filter using stepped impedance resonators

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2008
Cheng-Yuan Hung
Abstract In this letter, a novel dual-mode bandpass filter (BPF) using stepped impedance resonators (SIRs) for simultaneous low insertion-loss and wide passband has been designed. This novel wideband dual-mode BPF is formed by a microstrip square ring resonator with direct-connected orthogonal feed lines, and two impedance steps as perturbations. By varying the impedance ratio (K) of the SIRs, the wideband bandwidth can be tuned with more freedoms. The design procedure using the analysis of even and odd mode is described in this paper. The wideband BPF with relative bandwidth of 76.5% is simulated using the full wave electromagnetic simulation, and then fabricated and measured using the network analyzer. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1104,1107, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23281 [source]

Dual-band filter design of combined half and quarter wavelength SIRs for WLAN applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2008
Pow-Wen Chen
Abstract This article presents a dual-band bandpass filter composed of ,/2 and ,/4 stepped impedance resonators for the wireless local area network applications. The filter covers both the operating frequencies of 2.45 GHz and 5.2-5.8 GHz. The doubly parallel-coupling mechanism is used in the filter design to reduce the insertion losses and to gain a wider bandwidth. The cross coupling configuration and the tapped-line I/O feed are adopted in this filter design to provide the attenuation poles for improving the signal selectivity and stopband rejection levels. Experiments were conducted to verify the circuit performance. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 13,15, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22979 [source]

The design of a compact quasi-elliptic filter using stepped impedance resonators with harmonic suppression

Miniaturized elliptic bandpass filter using the novel coplanar double stepped impedance resonators

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2006
Suk-Hyung Jang
Abstract This paper presents the design and experimental results of the new miniaturized elliptic coplanar bandpass filter (EC BPF) using two types of double stepped impedance resonators (DSIRs) operating at a center frequency of 1.38 GHz. Miniaturization in the proposed BPF is achieved by connecting the transmission line between the middle of two SIRs contained in a single DSIR and both grounded planes. In addition, bond-wire bridges connected between both grounded planes (which are needed in various coplanar waveguide structures) are not required. The new four-pole EC-DSIR BPF shows good agreement with the simulation data obtained by full-wave EM simulations using Zeland IE3D ver. 10.06. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1059,1063, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21600 [source]