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Dual-band Bandpass Filter (dual-band + bandpass_filter)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Microstrip dual-band bandpass filters using parallel-connected open-loop ring resonators

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2008
Lung-Hwa Hsieh
Abstract This article proposes a microstrip dual-band bandpass filter that uses parallel-connected open-loop ring resonators. Compared to many microstrip dual-band filters, the advantages of using microstrip open-loop ring resonators are easy calculation (half-guided-wavelength), easy fabrication (equal width for all 50-, lines and without grounding holes), and direct connection to external feed lines (reducing insertion loss caused by gap couplings). Another advantage of the filter is an asymmetrical feed on the ring resonator that provides sharp rejections at its adjacent bands. The input and output matches of resonators to the external feed lines are derived using a simple transmission-line theory. The results of the derivation provide a simple design rule for filter designers. Simulated and measured results are presented with good agreement. The filter has minimum insertion loss of 1.25 dB at 1.85 GHz and 1.6 dB at 2.33 GHz. The 3-dB fractional bandwidths are 5.9% for the 1.9-GHz bandpass filter and 4.7% for the 2.4-GHz bandpass filter, respectively. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. [source]

Dual-mode dual-band bandpass filter based on double-sided parallel-strip line

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2009
Xiu Yin Zhang
Abstract This article presents a dual-mode dual-band bandpass filter based on double-sided parallel-strip line with an inserted conductor plane. Due to the isolation property of the conductor plane, this structure can provide two separate transmission paths to generate two passbands. No extra combination circuits are required at the input/output ports, simplifying the design and reducing circuit area. To demonstrate this idea, an experimental filter is implemented. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1361,1363, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24315 [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]

Design of dual-band bandpass filter using diverse quarter-wavelength resonators for GPS/WLAN applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2008
Hung-Wei Wu
Abstract The novel compact dual-band bandpass filter (BPF) by using diverse quarter-wavelength (,/4) resonators for global position system (GPS)/wireless local area network (WLAN) applications is proposed for the first time. The use of two interdigital-like ,/4 resonators of the proposed BPF effectively provides the responses for GPS/WLAN at 1.575/5.7 GHz by properly arranging the ,/4 SIRs. Full-wave simulator IE3D is used to design the proposed BPF. Good agreement with responses of electromagnetic (EM) simulation and measurement is compared. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2694,2696, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23716 [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]

A second-order dual-band bandpass filter using a dual-band admittance inverter

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2008
Hualiang Zhang
Abstract In this article, a second-order dual-band bandpass filter is designed. The filter consists of two dual-band resonators connected by a dual-band admittance inverter. The dual-band resonator unit is made of two shunt stubs that coordinately produce two resonances. A novel dual-band quarter-wavelength line acts as the admittance inverter, providing suitable admittance transformations. To verify the design concept, a filter working at 2 and 5 GHz is devised and fabricated on Rogers' RO3006 printed circuit boards. In addition, the dual-band filter is connected with a bandstop filter to suppress the unwanted spurious response. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1184,1187, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23326 [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]

Microstrip dual-band bandpass filter using slow-wave resonators for WLAN applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2007
Xuehui Guan
Abstract A dual-band bandpass filter using microstrip slow-wave resonators is developed for wireless local area network applications. The fundamental and higher order resonant harmonics of a microstrip open-loop resonator are analyzed against the length of the loading open stub. Then a dual-band bandpass filters is designed in the form of slow-wave open-loop resonators. A zero-degree feed structure is employed to produce transmission zeros near the passband to increase the rate of attenuations, and a quarter-wavelength feed line for impedance matching is added to get desired external quality factor at the input and output. The theoretical analysis and design procedures are successfully verified by experimental results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 14,16, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22055 [source]

High selective stepped-impedance dual-band bandpass filter

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2006
Jianpeng Wang
Abstract A high selective stepped-impedance dual-band bandpass filter is presented. The filter has a feature of two tunable passbands over a wide frequency range and compact size. A multi-coupling scheme is introduced so that two finite transmission zeros are generated between the two passbands to achieve a high out-of-band rejection. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1964,1966, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21831 [source]

A two-pole 900/1800-MHz microstrip filter for dual-band applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2006
Xuehui Guan
Abstract A two-pole 900/1800-MHz dual-band bandpass filter using microstrip open-loop resonators is proposed. Dual-band characteristics are obtained by using the fundamental and first spurious resonance of the resonators. Both the internal and external couplings of the filter are appropriately designed to simultaneously satisfy the dual-band requirements. The measured filtering characteristics of the designed filter agree well with the simulated responses. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1388,1391, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21639 [source]

Microstrip dual-band bandpass filters using parallel-connected open-loop ring resonators

Design a new structure 2.4 GHz/5.2 GHz dual-band bandpass filters on the MgTa1.5Nb0.5O6 ceramic

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2009
Cheng-Fu Yang
Abstract In this article, a ,/2 U-shaped hairpin resonator was contained in a modified end-coupled microstrip line. The increase of the sizes of U-shaped hairpin resonator and modified end-coupled microstrip line had no influence on the lower operating frequency and would shift the upper operating frequency to lower values. After finding the best designed parameters, a miniature dual-band microstrip bandpass filter with three transmission zeros generated in the stop-bands was developed on the MgTa1.5Nb0.5O6 microwave dielectric ceramic substrates. The dual-band filter had the central frequencies of 2.45 and 5.2 GHz and was suitable for the applications in the modern WLAN communication. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1085,1087, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24264 [source]