Mode Substrate Integrated Waveguide Cavity Research Articles

Low-Sidelobe Microstrip Patch Filtenna Array Fed by Higher Order Mode SIW Cavity

In this letter, a 1 × 3 microstrip patch (MP) filtenna array with low sidelobe level fed by TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">410</sub> -mode substrate integrated waveguide (SIW) cavity is investigated. Benefiting from the fact that the magnetic field amplitude at the adjacent region of the two central quasi-TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">110</sub> modes of the TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">410</sub> -mode SIW cavity is twice that of the single quasi-TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">110</sub> mode on either side of the edge, it enables the filtenna array to obtain a binomial power distribution and then achieve low sidelobe level. In the fusion design of filtering power divider (FPD), the SIW cavity and the patch radiators are regarded as first and second resonators of filter respectively, meanwhile, the power dividing function is fulfilled by the coupling process between them. For demonstration, a filtenna array prototype centered at 13.2 GHz is designed, fabricated and measured. The measured results show that a peak gain of 11.6 dBi and a maximum efficiency of 85%. The measured sidelobe levels in <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -planes are both below than -19.1 dB at 13.06 GHz and 13.32 GHz. Good agreement between the simulation and measurement can be observed.

Wideband power dividers usingmulti‐layersubstrate integrated waveguide and microstrip line coupling technology

In this paper, two wideband multi-layer substrate integrated waveguide (SIW) power dividers are proposed. Transitions based on microstrip-slotline-SIW coupling for TE40 mode SIW cavities are used to realize the out-of-phase and in-phase difference. The equivalent circuits are used to show the basic design guidelines and impedance matching for the two power dividers. To validate the design, two prototypes over 62.5% fractional bandwidth at 8.5 GHz center frequency are designed, good results can be found between the measurement and simulation results.

Compact and Wide Stopband Substrate Integrated Waveguide Bandpass Filter Using Mixed Quarter- and One-Eighth Modes Cavities

This letter presents the design of mixed quarter- and one-eighth modes substrate integrated waveguide (SIW) bandpass filter (BPF). The transmission zeros (TZs) of the proposed SIW BPF can provide wide stopband response and high selectivity characteristics by using different mode SIW cavities. For validation, two- and three-stage SIW BPFs with Chebyshev response were designed at a center frequency ( $f_{0}$ ) of 8 GHz. The measured results are consistent with the simulations. For two-stage BPF, the insertion loss smaller than 0.9 dB is measured within the passband of 0.65 GHz (7.75–8.4 GHz). The return loss higher than 19.7 dB is measured within the same passband. The spurious is produced at around 18 GHz ( $ ). The stopbands are attenuated more than 17.31 dB from the dc to 5.68 GHz ( $0.71f_{0}$ ) and from 9.28 GHz ( $1.16f_{0}$ ) to 16.67 GHz ( $2.08f_{0}$ ). The TZs are produced at 10 GHz and around 18 GHz due to a small cross-coupling between source/load and the interaction of the higher resonant modes of cavities, respectively. For three-stage BPF, the $\vert S_{21}\vert $ and $\vert S_{11}\vert $ smaller than −1.3 dB and −18 dB are measured within the passband of 7.57–8.45 GHz fractional bandwidth (FBW = 11%), respectively. The TZs are produced at 1.102, 1.9, and $2.39f_{0}$ and provide higher selectivity and attenuation compared to two-stage BPF.

Higher-order mode substrate integrated waveguide cavity excitation for microstrip patch antenna arrays at 30-GHz

This paper presents a novel approach to the design and fabrication of low-cost and high-gain aperture-coupled microstrip patch antenna (AC-MPA) arrays with improved radiation pattern for millimetre-wave applications such as simultaneous wireless information and power transfer (SWIPT) and Internet-of-Things (IoT) device connectivity. A higher-order mode substrate integrated waveguide (SIW) cavity is used to feed the MPA arrays through aperture coupling. The improved design approach is introduced and discussed in detail. Simulation and experimental results for 2 × 2 and 4 × 4 arrays are presented, demonstrating excellent agreement. Key performance metrics are side-lobe levels of less than −24 dB and −29 dB in the E-plane and −22 dB and −26 dB in the H-plane and realized gain of 11 dBi and 15 dBi for the 2 × 2 and 4 × 4 arrays respectively, at a design frequency of 30 GHz.

Compact High-Gain Metasurface Antenna Arrays Based on Higher-Mode SIW Cavities

This communication presents novel compact linearly/circularly polarized metasurface antenna arrays based on higher mode substrate integrated waveguide cavities. The linearly polarized antenna is realized by an array of patch cells with similar TM resonant modes as traditional patch antennas, while the circularly polarized one is newly designed based on the proposed polarization-rotation metasurface structure. Moreover, the periodic metasurface antennas are modified with complemental boundaries to further enlarge effective radiation apertures for about 1.5 dB gain enhancement. In addition, a simple TE220 higher mode cavity is employed as a compact and symmetrical feeding network to provide perfectly uniform four-way excitations, resulting in relatively uniform radiation aperture for high gain. The simulation and measured results both indicate that the proposed linearly/circularly polarized metasurface arrays can, respectively, achieve very high directional gains of about 10.75/10.66 dBi with aperture efficiencies of about 90% and low cross-polarization suppressions. In addition, 3 dB axial ratio beamwidths of the circularly polarized array can be up to 68° and 57° at two pitch planes of $\varphi = 0^{\circ }$ and 90°.

Half Mode Substrate Integrated Waveguide Cavity based RFID Chipless Tag

This study presents the design of a compact Radio Frequency Identification chipless tag, with reduced size, important quality factor and improved results. The proposed prototype is based on Substrate Integrated Waveguide technology using the Half-Mode Substrate Integrated Waveguide technique to reduce the tag size by the half and preserve the same response. Further, the operating frequency band is from 5.5 to 8 GHz inside a compact surface of 1.3 × 5.7 cm². The frequency domain approach is adopted based on the frequency shift coding technique.

Broadband Dual Circularly Polarized Substrate Integrated Waveguide Antenna

In this letter, a broadband dual circularly polarized substrate integrated waveguide (SIW) antenna is proposed. The proposed antenna consists of a quarter mode SIW cavity, two open-stubs and defected ground structures (DGSs). The antenna has two ports. One of them provides left-hand circular polarization and the other provides right-hand circular polarization. Circular polarization is obtained from TE202 mode of the quarter mode resonator. The cavity loaded with two perpendicular open-stubs at the corner provides dual mode resonance, which is then utilized to increase circular polarization bandwidth of the antenna. Furthermore, DGSs are used to improve isolation between the ports. The measured 3 dB axial ratio (AR) bandwidth of the antenna is approximately 11.2% at 12.5 GHz with a return loss more than 10 dB over the band.

Miniaturized half mode substrate integrated waveguide cavity resonator and filter with good spurious suppression

A miniaturized cavity resonator based on the half mode substrate integrated waveguide (HMSIW) technology is proposed and investigated in this paper to reduce the circuit area of a conventional substrate integrated waveguide (SIW) cavity resonator much more. Such a miniaturized resonator is built up by a two-layer HMSIW cavity loaded with a modified complementary split ring resonator (CSRR) etched on its middle conductor plate. Then, the proposed miniaturized cavity resonator is employed to design an S-band fourth-element bandpass filter. The center frequency is 3 GHz and the average insertion loss is 1.2 dB within the in-band. The total circuit area is only , i.e., 7% of the size of a conventional SIW fourth-element bandpass filter. It presents a good and wideband spurious suppression because the first higher order resonant mode of the used resonator is far away from the operation band. Experimental and simulated results are in good agreement, both validating our design concept.

Tunable Ferroelectric Ceramic Components for Reconfigurable Wireless Communications

This paper focuses on the technology evolvement and novel concepts of ferroelectric microwave components. They aim to enable reconfigurable wireless frontends for frequency-agile, software-defined and cognitive radios. Such components are an emerging technology based on the nonlinear solid state ferroelectric materials like Barium-Strontium-Titanate namely BST thick-films. They are expected to cope with the demands of multiband and multi-standard operation. Processing and integration technologies are revised to enable multilayer component realization, including selective sol-gel printing and vertical connection through laser drilling. Several novel kernel frontend components based on ferroelectric thick-film ceramic are addressed then. The challenging trend of antennas towards compactness with wider spectrum coverage is coped with several tunable resonant modes in the antennas with integrated BST varactors. The optimized prototype for frequency division duplex services covers 1.47 GHz to 1.76 GHz with a variable distance between up- and down-link channels. The environmental impact on antennas can be compensated by tunable matching networks. In the commercial frequency range from 1.8 GHz to 2.1 GHz, a demonstrative module exhibits an insertion loss less than 0.98 dB, in a compact multilayer package. A compact bandpass filter is enabled by an evanescent mode substrate integrated waveguide cavity in ferroelectric ceramics, integrated with tunable complementary split ring resonator scatterers and tunable matching networks. The compact module covers 2.95 GHz to 3.57 GHz with a comparatively low insertion loss.

Novel Compact Bandpass Filter Based on Folded Half Mode Substrate Integrated Waveguide Cavities

This paper proposed a novel compact bandpass filter with folded half mode substrate integrated waveguide (FHMSIW) cavities using two-layer printed circuit board(PCB) process. The area of the FHMSIW filter is reduced by nearly 50 % and 75 % compared with half mode substrate integrated waveguide(HMSIW) filter and substrate integrated waveguide(SIW) filter, respectively. A four-pole Chebyshev FHMSIW bandpass filter at C-band has been designed, simulated and fabricated. Measured results are presented and found to agree with the full-wave simulated results by using Ansoft HFSS. The filter shows good performance and compact size.

Development of Ultrawideband Antenna With Multiple Band-Notched Characteristics Using Half Mode Substrate Integrated Waveguide Cavity Technology

Investigations on planar ultrawideband (UWB) antenna with multiple band-notched characteristics based on half mode substrate integrated waveguide technology are presented. The proposed antenna consists of a planar UWB monopole antenna and a half mode substrate integrated waveguide cavity which can generate multiple stopbands by proper arrangement. Planar antennas with dual, triple and quadruple notched bands are designed and implemented. The notched frequencies and their bandwidths can be adjusted according to specification by altering the cavity and feed line independently. These antennas are fabricated with two-layer printed circuit board (PCB) process. Sharp and high band rejection, narrow frequency notches are achieved, which are in good agreement with the simulated results. This technique is suitable for designing wideband antenna with multiple frequency notches or for creating multiband antennas.

Substrate integrated waveguide (SIW) asymmetric dual-mode filter and diplexer

Substrate integrated waveguide (SIW) can be used to implement high Q waveguide components with the same easy and low-cost fabrication process as planar circuits. In this paper two inline three-pole dual-mode filters with asymmetric transmission response based on SIW are presented. These two filters, consisting of a TE102-TE301 dual-mode SIW cavity and a TE101 mode SIW cavity, are centred at around 10 GHz with a transmission zero on the left of the passband and the right of the passband, respectively. Based on the two kinds of three-pole deal-mode filters, a diplexer with isolation better than 35 dB is developed. A linear microstrip taper is used to implement the transition between microstrip and SIW. The measured results agree with simulated results.