A dual-mode rectangular ring bandpass filter with transmission zeros on LTCC

Purpose The purpose of this paper is to present the design of a compact microstrip bandpass filter (BPF) in dual-mode configuration loaded with cross-loop and square ring slots on a square patch resonator for C-band applications. Design/methodology/approach In the proposed design, the dual-mode response for the filter is realized with two transmission zeros (TZs) by the insertion of a perturbation element at the diagonal corner of the square patch resonator with orthogonal feed lines. Such TZs at the edges of the passband result in better selectivity for the proposed BPF. Moreover, the cross-loop and square ring slots are etched on a square patch resonator to obtain a miniaturized BPF. Findings The proposed dual-mode microstrip filter fabricated in RT/duroid 6010 substrate using PCB technology has a measured minimum insertion loss of 1.8 dB and return loss better than 24.5 dB with a fractional bandwidth (FBW) of 6.9%. A compact size of 7.35 × 7.35 mm2 is achieved for the slotted patch resonator-based dual-mode BPF at the center frequency of 4.76 GHz. As compared with the conventional square patch resonator, a size reduction of 61% is achieved with the proposed slotted design. The feasibility of the filter design is confirmed by the good agreement between the measured and simulated responses. The performance of the proposed filter structure is compared with other dual-mode filter works. Originality/value In the proposed work, a compact dual-mode BPF is reported with slotted structures. The conventional square patch resonator is deployed with cross-loop and square ring slots to design a dual-mode filter with a square perturbation element at its diagonal corner. The proposed filter exhibits compact size and favorable performance compared to other dual-mode filter works reported in literature. The aforementioned design of the dual-mode BPF at 4.76 GHz is suitable for applications in the lower part of the C-band.

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Miniaturized Dual-Band Bandpass Filter Using Embedded Dual-Mode Resonator with Controllable Bandwidths

Frequenz ◽

10.1515/freq-2015-0195 ◽

2016 ◽

Vol 70 (9-10) ◽

Author(s):

Chuanming Zhu ◽

Jin Xu ◽

Wei Kang ◽

Zhenxin Hu ◽

Wen Wu

Keyword(s):

Insertion Loss ◽

Degrees Of Freedom ◽

Bandpass Filter ◽

The Other ◽

Dual Band ◽

Dual Mode ◽

Transmission Zeros ◽

Low Insertion Loss ◽

Multiple Transmission ◽

Mode Resonator

AbstractIn this paper, a miniaturized dual-band bandpass filter (DB-BPF) using embedded dual-mode resonator (DMR) with controllable bandwidths is proposed. Two passbands are generated by two sets of resonators operating at two different frequencies. One set of resonators is utilized not only as the resonant elements that yield the lower passband, but also as the feeding structures with source-load coupling to excite the other to produce the upper passband. Sufficient degrees of freedom are achieved to control the center frequencies and bandwidths of two passbands. Moreover, multiple transmission zeros (TZs) are created to improve the passband selectivity of the filter. The design of the filter has been demonstrated by the measurement. The filter features not only miniaturized circuit sizes, low insertion loss, independently controllable central frequencies, but also controllable bandwidths and TZs.

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Dual-mode resonator filter with improved feed-lines for dual-band applications

Journal of Electrical Engineering ◽

10.2478/jee-2020-0060 ◽

2020 ◽

Vol 71 (6) ◽

pp. 433-435

Author(s):

Shan Shan Gao ◽

Jia-Lin Li ◽

Zhe Lin Zhu ◽

Jia Li Xu ◽

Yong Xin Zhao

Keyword(s):

Simple Structure ◽

High Selectivity ◽

Bandpass Filter ◽

Dual Band ◽

Dual Mode ◽

Transmission Zeros ◽

Good Consistency ◽

Mode Resonator

AbstractAn improved feedline configuration for dual-mode resonator filter is investigated in this paper. Based on the introduced topology, a dual-mode dual-band bandpass filter with center frequencies of 1.8 and 2.4 GHz is optimally designed, fabricated and tested. The introduced dual-band bandpass filter has simple structure and enables high selectivity to be realized due to two pairs of transmission zeros located near to the lower and upper passband, respectively. Both measured and simulated performances are presented with good consistency.

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A novel crossed slotted patch dual-mode bandpass filter with two transmission zeros

Microwave and Optical Technology Letters ◽

10.1002/mop.23219 ◽

2008 ◽

Vol 50 (3) ◽

pp. 741-744 ◽

Cited By ~ 6

Author(s):

Sean Wu ◽

Min-Hang Weng ◽

Shih-Bin Jhong ◽

Maw-Shung Lee

Keyword(s):

Bandpass Filter ◽

Dual Mode ◽

Transmission Zeros

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Multilayer SIW Dual-Band Filters with Independent Band Characteristics and High Selectivity

Frequenz ◽

10.1515/freq-2019-0024 ◽

2019 ◽

Vol 73 (9-10) ◽

pp. 293-300

Author(s):

Dinghong Jia ◽

Jianqin Deng ◽

Yangping Zhao ◽

Ke Wu

Keyword(s):

High Selectivity ◽

Bandpass Filter ◽

Large Range ◽

Metal Layer ◽

Dual Band ◽

Effective Dimension ◽

Dual Mode ◽

Transmission Zeros ◽

Design Freedom ◽

Good Agreement

Abstract This work presents an approach to developing dual-mode dual-band substrate integrated waveguide (SIW) bandpass filter based on multilayer process. TE102/TE201 and TE101/TE102 modes are used to feature the two passbands, respectively. To begin with, large range of band location ratios are decided by the effective dimension of the SIW resonator. With reference to the field distribution, independent coupling schemes of the dual-modes are then realized by slots or circular apertures etched on the middle metal layer. It allows to not only introduce a large design freedom of bandwidth but also keep compactness. Finally, source-load and mixed couplings are deployed to produce transmission zeros around the passband in providing a sharp selectivity in the two filters, respectively. The details to independently control the center frequencies and bandwidth of two passbands are also presented. A two-order double-layered and a triple-layered SIW dual-band bandpass filter are prototyped to evaluate the proposed design approach, respectively. Results show a good agreement between simulations and measurements. The proposed filter exhibits flexible design freedom, high selectivity as well as good out-of-band rejection.

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Compact dualband bandpass filter with two transmission zeros using dual-mode microstrip resonator and tapped-line geometry

Microwave and Optical Technology Letters ◽

10.1002/mop.25627 ◽

2010 ◽

Vol 53 (1) ◽

pp. 108-111 ◽

Cited By ~ 1

Author(s):

Tae-Soon Yun ◽

Sun-Kuk Noh ◽

Hyung-Jong Kim ◽

Euy-Kyo Oh ◽

Hong-Min Son ◽

...

Keyword(s):

Bandpass Filter ◽

Line Geometry ◽

Dual Mode ◽

Microstrip Resonator ◽

Transmission Zeros

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A Dual-Mode Bandpass Filter with Multiple Controllable Transmission-Zeros Using T-Shaped Stub-Loaded Resonators

The Scientific World JOURNAL ◽

10.1155/2014/572360 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Zh. Yao ◽

C. Wang ◽

N. Y. Kim

Keyword(s):

High Selectivity ◽

Bandpass Filter ◽

Second Harmonic ◽

Center Frequency ◽

Harmonic Frequency ◽

Dual Mode ◽

Mode Theory ◽

Transmission Zeros ◽

Coupling Capacitance ◽

Compact Size

A dual-mode broadband bandpass filter (BPF) with multiple controllable transmission-zeros using T-shaped stub-loaded resonators (TSSLRs) is presented. Due to the symmetrical plane, the odd-even-mode theory can be adopted to characterize the BPF. The proposed filter consists of a dual-mode TSSLR and two modified feed-lines, which introduce two capacitive and inductive source-load (S-L) couplings. Five controllable transmission zeros (TZs) can be achieved for the high selectivity and the wide stopband because of the tunable amount of coupling capacitance and inductance. The center frequency of the proposed BPF is 5.8 GHz, with a 3 dB fraction bandwidth of 8.9%. The measured insertion and return losses are 1.75 and 28.18 dB, respectively. A compact size and second harmonic frequency suppression can be obtained by the proposed BPF with S-L couplings.

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