A Novel of Dual-Band Bandpass Filter Employing Coupled Stepped Impedance Resonator and U-Shaped Defected Microstrip Structure (DMS)

Due to the progression growth of multiservice wireless communication systems in a single device, multiband bandpass filter has attract a great attention to the end user. Therefore, multiband bandpass filter is a crucial component in the multiband transceivers systems which can support multiple services in one device. This paper presents a design of dual-band bandpass filter at 2.4 GHz and 3.5 GHz for WLAN and WiMAX applications. Firstly, the wideband bandpass filter is designed at a center frequency of 3 GHz based on quarter-wavelength short circuited stub. Three types of defected microstrip structure (DMS) are implemented to produce a wide notch band, which are T-inversed shape, C-shape, and U- Shape. Based on the performance comparisons, U-shaped DMS is selected to be integrated with the bandpass filter. The designed filter achieved two passbands centered at 2.51 GHz and 3.59 GHz with 3 dB bandwidth of 15.94 % and 15.86 %. The proposed design is very useful for wireless communication systems and its applications such as WLAN and WiMAX

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Novel Spurious Suppression Approach for SIR Dual-band Bandpass Filter Design

Frequenz ◽

10.1515/freq-2014-0055 ◽

2014 ◽

Vol 69 (1-2) ◽

pp. 65-70

Author(s):

Jianzhong Chen ◽

Xuefeng Li ◽

Hongyu Shi ◽

Anxue Zhang

Keyword(s):

Bandpass Filter ◽

Filter Design ◽

Stop Band ◽

Design Approach ◽

Dual Band ◽

External Quality ◽

Resonant Frequencies ◽

Coupling Property ◽

Spurious Suppression ◽

Stepped Impedance Resonator

Abstract A new design approach for a stepped impedance resonator (SIR) dual-band bandpass filter (BPF) with high multi-spurious suppression is proposed in this paper. The external coupling property of an SIR at multi-order resonant frequencies is fully studied. Different input impedances at desired frequencies are achieved by optimizing the unequal impedance transformer. The new solution shows the freedom in the choice of tapping point. The external quality values of multi-order harmonics vary with the shift of the tapping position. Wide upper stop-band rejection is realized by mismatching Qe at the unwanted harmonic frequencies, while keeping the Qe suitable for operating dual band to obtain good in-band performance. A traditional dual-band BPF and a novel practical BPF operated at 2.45/5.25 GHz are designed and fabricated to demonstrate the above idea. Good simulated and measured results are presented.

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Compact Quad-Band Bandpass Filter Using Double-Diplexing Structure

Frequenz ◽

10.1515/freq-2016-0236 ◽

2017 ◽

Vol 71 (11-12) ◽

Author(s):

Jin Xu ◽

Yan Zhu ◽

Yong-Qian Du

Keyword(s):

Bandpass Filter ◽

Dual Band ◽

Coupled Lines ◽

Lumped Elements ◽

Stepped Impedance Resonator ◽

Channel Filter ◽

Channel Filters

AbstractThis paper presents a compact quad-band bandpass filter (QB-BPF) using double-diplexing structure, which consists of two channel filters and a pair of modified manifold-coupled lines. Each channel filter is realized by the asymmetrical coupling shorted stub loaded stepped-impedance resonator (SSLSIR) dual-band bandpass filter (DB-BPF), and the modified manifold line constructed by lumped elements is proposed to connect two channel filters to constitute the QB-BPF. The fabricated QB-BPF occupies a compact circuit size of 0.178λ

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Harmonic suppressed coupled stepped-impedance resonator based dual-band tunable bandpass filter

Engineering Science and Technology an International Journal ◽

10.1016/j.jestch.2017.09.006 ◽

2017 ◽

Vol 20 (5) ◽

pp. 1460-1465

Author(s):

Amarjit Kumar ◽

Nagendra Prasad Pathak

Keyword(s):

Bandpass Filter ◽

Dual Band ◽

Stepped Impedance Resonator ◽

Tunable Bandpass Filter

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Dual-Band BPF Using Simple SIR Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.655-657.1614 ◽

2013 ◽

Vol 655-657 ◽

pp. 1614-1618

Author(s):

Wen Ko ◽

Man Long Her ◽

Yu Lin Wang ◽

Ming Wei Hsu

Keyword(s):

Transmission Line ◽

Bandpass Filter ◽

Low Frequency ◽

Basic Structure ◽

Simulation Software ◽

Dual Band ◽

Center Frequency ◽

Resonant Circuit ◽

In Series ◽

Stepped Impedance Resonator

This paper studies a very simple structure for dual-band bandpass filter. Filter is composed of two asymmetric coupled resonator circuit by two sets of different size stepped impedance resonator. This circuit applied microstrip line, coupling principle and impedance ratio by controlling the stepped impedance resonator to control the center frequency 2.6/5.2 GHz of the first and the second bandpass filter. The basic structure of the filter is constituted by the three sections of transmission line and two sets of SIR, that is, in two gaps of the three sections of transmission line parallel connection the equivalent inductances and capacitor of the two sets of SIR in series with the resonant circuit (LCL) to constitute bandpass filter. The low frequency 2.6 GHz is through the upper half of low impedance SIR, and the high frequency 5.2 GHz is through the lower half of high impedance SIR. This paper presents the design of asymmetric SIR-based dual-band bandpass filter, the filter structure is simple, easy to produce and can control the characteristics of the passband center frequency. By electromagnet simulation software( IE3D ) to simulate, the actual production of the circuit using a vector analyzer measurement, simulation and measurement results show good consistency.

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