SIW Bandpass Filter Research Articles

Compact flat folding SIW bandpass filter utilizing GaAs-based IPD process

Compact flat folding SIW bandpass filter utilizing GaAs-based IPD process

A Miniaturized C-B and SIW Bandpass Filter based on LTCC

In this paper, a miniaturized bandpass filter based on low temperature co-fired ceramic (LTCC) technology is proposed. The miniaturization is achieved by two double folded substrate integrated waveguide (DFSIW) resonant cavities. By interconnecting LTCC three-dimensional structure, the resonant cavities can be stacked vertically. Compared with the conventional SIW filter, the size is reduced by 75.6%. The experimental results show that the low insertion loss and good selectivity are achieved. The proposed miniaturized bandpass filter is promising for 5G application.

Miniaturized and optimized half mode SIW bandpass filter design integrating Hilbert cells as DGS

ABSTRACT This paper demonstrates a novel configuration of half mode substrate integrated waveguide HMSIW bandpass selective filter based on Hilbert cells as DGS. Two 50-Ohm conventional micro-strip are used as feed lines. The filter is designed and optimized using CST Software, Where a parametric study is used to optimize its geometric parameters. In our design, six periodic Hilbert cells are used, which are work collectively with three transverse slots to generate the desired resonance frequency. The used dielectric substrate is FR4 with a relative permittivity of 4.3. The proposed filter operates at the frequency of 3.25 GHz with an insertion loss about of −2 dB and a rejection extended from 1 GHz to 3.2 GHz and from 3.4 GHz to 7 GHz respectively for the lower and the higher sides with a level more than −35 dB. The filter is fabricated and measured, where the obtained measurements show a clear crystal similarity with the simulated results. The proposed filter is considered for TD LTE applications.

Design of Hybrid Fractal Integrated Half Mode SIW Band Pass Filter with CSRR and Minkowski Defected Ground Structure for Sub-6 GHz 5G Applications

A compact and wide-stop band half mode substrate integrated waveguide (HMSIW) filter, incorporated with a hybrid fractal on the upper plane and a complementary split ring resonator (CSRR), along with a defected ground structure (DGS) etched on the bottom plane, is proposed for 5G sub-6 GHz application. A CSRR reduces the resonant frequency causing size miniaturisation by approximately 40% by augmenting the equivalent inductance and capacitance of the CSRR. Further, the low-pass characteristics of the DGS aid in suppressing out-of-band spurious harmonics. A two-pole band pass filter (BPF) is fabricated using FR4 (flame retardant) to validate the design. The results confirm that the proposed filter has a pass band from 3.75 GHz–5.12 GHz with spurious response below −20 dB > 4f0.

TSV-based SIW bandpass filter for W-band mobile communication applications

TSV-based SIW bandpass filter for W-band mobile communication applications

A sixth‐order SIW bandpass filter based on combining single‐ and dual‐mode cavities with high selectivity at Ka‐band

In this paper, a novel substrate integrated waveguide quasi-elliptic bandpass filter is proposed by combining single- and dual-mode cavities. Two single-mode cavities with TE101 mode are directly coupled to the dual-mode resonance cavity which employs a pair of disturbing metallic via-holes to make the resonant points of TE101 and TE102 mode in one passband. Based on the conventional box-like topology, two additional single cavities are used to achieve wider bandwidth and simplify the design difficulty. In addition to two transmission zeros (TZs) realized by the cross-coupling technology, nonreasoning node will generate an additional TZ at a higher frequency to improve the upper stopband performance. Finally, a sixth-order filter, having the passband frequency of 24.25–27.5 GHz for 5G application, with three TZs, is simulated, fabricated and measured to demonstrate and verify the proposed structure. The test results show the insertion loss is 1.7 and 3 dB bandwidth is 3.37 GHz. The three TZs improve out of band rejection of the filter.

Design of Complementary Hexagonal Metamaterial Based HMSIW Band-Pass Filter and Reconfigurable SIW Filter Using PIN Diodes

This paper is divided into two sections, in the first section, a new SIW and a half-mode SIW band-pass filters based on complementary hexagonal metamaterial cells (C-HMCs) are proposed. Firstly, the SIW is analyzed in case of using two C-HMC cells and in the case of using four of these cells. Secondly, the HMSIW tunable BPF is studied and optimized. The size of the half mode is reduced by almost 50%. This filter design has a very high insertion loss about -0.4 dB, and significant transmission bandwidth extending from 5.9 GHz to 6.5 GHz. In the second section of this paper, an electronically reconfigurable SIW band-pass filter is proposed. By implementing two PIN diodes in the gaps of the two C-HMC, the results of turning the diodes ON or OFF individually is a switching in the frequency center, between 5.8 GHz and 6.8 GHz. Also, a dual band with two frequency centers at (5.6 GHz and 7.4 GHz) is achieved by turning both of the diodes ON. In addition, the metamaterial properties of all the proposed filters are investigated and presented in this work.

A high-selectivity double-mode SIW bandpass filter utilizing the modified parallel coupled microstrip lines

ABSTRACT In this article, a high-selectivity double-mode substrate integration waveguide bandpass filter utilizing modified parallel coupled microstrip lines (MPCML) is presented. The designed method is analyzed in detail. Six metal vias are designed to perturb TE-101 mode and TE-103 mode. The resonant frequency of the perturbed TE-101 mode is shifted to high frequency, close to that of TE-102 mode, which caused the formation of passband. The resonant frequency of the perturbed TE-103 mode is shifted to high frequency, improving out-of-band performance. Simultaneously, the coplanar waveguide structure is used to adjust the external quality factor. Two rectangular slotlines are introduced to adjust center frequency and bandwidth slightly. Two rectangular stubs are designed for better source and load matching. Three transmission zeros (TZs) are obtained to improve the selectivity. The designed MPCML promotes the generation of TZs. Another TZ is obtained by the coupling between TE-102 mode and TE-103 mode. The designed filter operates at 14.4 GHz with bandwidth of 800 MHz. The measured return loss is better than 15 dB, and the minimum insertion loss is 1.60 dB. The measurement is agreed with the simulation.

Liquid metal frequency‐reconfigurable SIW bandpass filter based on gravity field

Liquid metal frequency‐reconfigurable SIW bandpass filter based on gravity field

Si-based Ka-band SIW band-pass filter using wafer level manufacturing process

Si-based Ka-band SIW band-pass filter using wafer level manufacturing process

Analysis of Eighth-Mode Substrate-Integrated Waveguide Cavity and Flexible Filter Design

In this paper, a systematic research campaign on eighth-mode substrate integrated waveguide (EMSIW) filters is reported. The sizes of these EMSIW resonant cavities are only one-eighth or one-sixteenth of a conventional SIW resonant cavity. Two different coupling topologies, i.e., electric coupling and magnetic coupling, are employed between two EMSIW resonant cavities, which are analyzed theoretically via the response of the structure and the relationship between the cavities. Both coupling topologies enable structural variations that possess advantages and flexibility of the second-order EMSIW bandpass filters (BPFs) designing. By utilizing these basic coupling mechanisms, multilayer board technology, and other practical techniques, a class of triple-order SIW BPFs with the merits of compact size and high selectivity are demonstrated. Specifically, several triple-order EMSIW BPFs composed of pure EMSIW cavities or comprised by combining EMSIW and quarter-mode SIW cavities are simulated, fabricated, and measured for verification.

A quasi-elliptic response triple-mode SIW bandpass filter with controllable transmission zeros

A quasi-elliptic response triple-mode SIW bandpass filter with controllable transmission zeros

A novel wideband half-mode SIW bandpass filter based on evanescent-mode technique using complementary Z-shaped resonator

In this paper, a novel wideband bandpass filter using half-mode substrate integrated waveguide (HMSIW) structure loaded by complementary Z-shaped resonator (CZR) is proposed. The working principle of the proposed filter is based on the evanescent-mode propagation. The CZR unit-cell behave as a magnetic dipole, which is able to generate a backward-wave passband region below the cut-off frequency of the SIW–CZR structure. Since, the electrical size of the proposed CZR unit-cell is larger than the conventional complementary electric-LC unit-cell with the same size, therefore this unit-cell is a good candidate to miniaturize the SIW structure. As well as, the SIW filter loaded by the proposed CZR unit-cell presents a wider bandpass compared to the SIW filter loaded by the conventional resonant metamaterial unit-cells. In order to validate the ability of the proposed CZR unit-cell in size reduction and increasing bandwidth, the proposed one- and two-stage HMSIW–CZR filters have been fabricated and tested. The measured S-parameters of the fabricated filters are in a good agreement with the simulated ones. It is the first time that the CZR unit-cells were combined with the SIW structure to miniaturize the SIW structure and increase the bandwidth. The total size of the proposed two-stage filter is 0.62 λg × 0.26 λg.

Compact half-mode SIW bandpass filter with high-frequency selectivity

ABSTRACTThis article presents a compact bandpass filter (BPF) using half-mode substrate integrated waveguide technology. The source-load cross-coupling structure has been used in the BPF and the transmission zeroes have been generated to improve the frequency selectivity. The proposed filter is smaller than its conventional substrate integrated waveguide counterpart with similar filter specifications and has advantages of high-frequency selectivity and miniaturization. The measured results show that the designs can provide 170 MHz bandwidth at 3.5 GHz with a return loss of 15.1 dB and an insertion loss of 2.1 dB.

Miniaturizing SIW Filters with slow wave Technique

Filters are an inevitable part of any communication system. State-of-the-art devices are designed with miniaturization as an important criterion. Though miniaturization gained considerable attention, application of slow wave technique as a miniaturizing technique wasn’t explored much. Furthermore, the analysis of slow wave filters in terms of its characteristic parameters like slow wave factor (SWF) and group delay has not yet been attempted. This work performs a comparative study of miniaturized inductive post and iris substrate integrated waveguide SIW band-pass filters. Inductive post and iris filters are designed, fabricated and analyzed. Implementation of slow wave requires a double layer topology, which results in physically separating the electric and magnetic fields. This helps in miniaturization. Application of slow wave technique improved the insertion loss by 0.23% for the inductive post filter and 7.53% for iris filter. SWF and group delay were found to be better in the iris filter. The inductive post filter was 38.17% and 61.36% miniaturized in size and area, respectively and iris filter, 56.35% and 72.72%, respectively. The miniaturized iris filter was fabricated and the results were validated by measurements. The quality factor for miniaturized iris and inductive post filters were found to be 918.45 and 755.15 respectively.

Compact in-line triplet SIW bandpass filter using etched GCPW line resonator

Compact in-line triplet SIW bandpass filter using etched GCPW line resonator

Substrate-integrated waveguide band pass filters with frequency-dependent coupling elements

An effective technique to improve the stop-band frequency response of direct-coupled resonators in substrate-integrated waveguide SIW technology is introduced. Regular inductive-iris filters in SIW technology are supplemented with H-plane frequency-dependent inverters which not only create transmission zeros but also serve as the proper impedance inverter. A synthesis technique is introduced to prescribe transmission zeros at finite frequencies on either side of the pass band, symmetrically or asymmetrically. Two different topologies of frequency-dependent inverters for X-band SIW band pass filters demonstrate that attenuation poles can be created on both side of the passband and significantly improve the filters' stop-band performences. Measurements confirm the validity of the presented design approach. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:237-242, 2014.

V-band cross-coupled SIW band-pass filter with an antisymmetric U-slot negative coupling structure

This study presents an low-temperature cofired ceramic (LTCC) V-band cross-coupled band-pass filter using substrate-integrated waveguide cavities. Two antisymmetric U-shaped slots connected by via is proposed to construct the negative coupling structure, which is simple and especially useful for 60 GHz applications. Moreover, the U-slot structure possesses a wide range of realizable coupling coefficients from −0.008 to −0.075. An experimental LTCC fourth-order filter was fabricated for demonstration, achieving a bandwidth of 12% (7.2 GHz) at 59.6 GHz with superior frequency selectivity.

A Novel Planar Extended Doublet Filter with Substrate Integrated Waveguide Cavity Resonators

A novel planar extended doublet filter based on substrate Integrated waveguide cavity resonators was proposed for the first time. This filter consists of a main doublet with an additional resonator grown in one of the branches. The source and load are coupled to both branches of the doublet in order to generate two transmission zeros. By employing the combinational structure of the TE101-mode and TE102-mode of the SIW cavity resonators, the negative coupling coefficient required for the design of a single-layer cross-coupled SIW bandpass filter is implemented. The measurement results show the return loss of the implemented filter is above 13dB, the insertion loss is below 4.238dB with only 0.56% of the bandwidth.