Half-mode Substrate Integrated Waveguide Resonator Research Articles

Hybrid self-oscillating mixer loading dielectric resonator antenna fed by half-mode substrate integrated waveguide for K-band radar

In this paper, a new self-oscillating mixer (SOM) including a dielectric resonator (DR) antenna fed by a half-mode substrate integrated waveguide (HMSIW) has been proposed using hybrid integrated circuit technique on an FR4 epoxy substrate. The HMSIW resonator with high quality factor and the DR radiator with higher order HEM13δ mode excitation are responsible for the excellent phase noise performance of the oscillator and the high directivity of the antenna, respectively. The phase noise, estimated LO power, and conversion gain were obtained as −102.5 dBc/Hz at 1 MHz offset, 8.74 dBm at an oscillation frequency of 24.15 GHz, and 8.5 dB, respectively. The figure-of-merit for the oscillator was obtained −172.8 dBc/Hz.

SIW Resonator-Based Duplex Filtenna

In this communication, a low-profile single-layered duplex-filtenna scheme is proposed by using two feeds, and a common substrate integrated waveguide (SIW) cavity. A rectangular slot is carved on the top of the cavity along the narrower side of the SIW, which splits the cavity into two unequal parts. Each part behaves as a half-mode SIW (HMSIW) resonator which radiates with the help of an additional longitudinal slot and open-end of HMSIW when excited with corresponding feed. Also, two vias have been loaded along the broad side of the transverse slot to tune the impedance bandwidth and improve the selectivity in the passbands. The working process of both HMSIW resonators is similar, thus similar type of electrical performance is expected. By properly optimizing the locations of these vias and transverse-slot dimensions, high isolation between input ports is realized. To validate the proposed concept, design has been fabricated and measured. The measured results show good agreement with the simulated counterparts. The measured result shows that the design exhibits impedance bandwidths of around 3.0% (8.63–8.88 GHz) and 4.2% (9.26 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ - $</tex-math></inline-formula> 9.66 GHz) for lower and upper-frequency pass channel, respectively. The measured average realized gains in the broadside direction are 3.51 and 4.10 dBi, respectively.

Triangular Cavity Multi-Passband HMSIW Filter Based on Odd-Even Mode Analysis

This letter proposes a multi-passband half-mode substrate integrated waveguide (HMSIW) filter based on the theory of odd and even mode analysis. The filter adopts a triangular HMSIW cavity cut along the diagonal of the rectangle. By etching two dual-mode resonators, the resonant mode of the HMSIW resonator is coupled with the odd-even mode of the dual-mode resonator to achieve multiple passbands. The defected ground structure (DGS) of the filter can reduce the resonance frequency of the HMSIW cavity without increasing the volume of the HMSIW cavity, making it easier to couple with the odd and even mode frequencies of the resonator. The input and output ports are directly coupled through a microstrip line. In this way, it adds an additional coupling path to the filter, which increases the out-of-band suppression without changing the performance in the passband, and improves the overall performance of the filter. To prove the feasibility of the above method, a multi-passband HMSIW filter was fabricated and tested. The center frequencies of the three passbands of the filter are 2.98 GHz, 4.78 GHz, and 6.62 GHz, respectively. The return loss in the passband is better than −15 dB, and the insertion loss is better than 2 dB. The measured results have a good agreement with the simulation results.

Compact HMSIW four‐way filtering power divider with pre‐defined division ratio

A novel and simple design approach of compact four-way filtering power divider (FPD) using half-mode substrate integrated waveguide (HMSIW) cavity is investigated in this letter. The pre-defined power division ratio of the four outputs is obtained by adjusting the external quality factor (Qe) of each output port, while the total output Qe is equal to the input Qe. The four outputs are loaded to a single HMSIW resonator, achieving a compact size. Meanwhile, both bandpass response and power division can be designed independently. For demonstration, a prototype with pre-defined power division ratio of 1:3:3:1 is designed, fabricated, and measured. The measured results show that the FPD centered at 4.88 GHz owns a 3-dB fractional bandwidth (FBW) of 11.3%. The insertion loss of the passband is about 1.4 dB and the return loss is better than 17 dB, meanwhile the phase differences of in-phase four outputs are all within 5° from 4.61 to 5.16 GHz. Good agreement is observed between the simulated and measured results.

A Bandpass Filter Using Half Mode SIW Structure with Step Impedance Resonator

This paper presents a miniaturized bandpass filter, which uses half mode substrate integrated waveguide (HMSIW) structure with embedded step impedance structure (SIS). By embedding the stepped impedance structure into the top metal of the waveguide cavity, the center frequency can be quickly shifted to a lower frequency. The operating center frequency of the proposed bandpass filter (BPF) using HMSIW resonators with embedded SIS is tunable as functions of the parameters of the SIS. The design curve is provided. A filter example of the center frequency of the filter at 3.5 GHz is fabricated and measured, having the insertion loss |S21| less than 3 dB, and the return loss |S11| greater than 10 dB. The transmission zeros are located at 2.95 GHz and 3.95 GHz on both sides of the passband, both of which are lower than 30 dB. The simulation result and the measured response conform to the proposed design concept. The proposed HMSIW filter design is in line with the current 5G communication trend.

Dual‐passbandbandpass‐filteringpower divider usinghalf‐modesubstrate integrated waveguide resonator with high frequency selectivity

In this paper, a half-mode substrate integrated waveguide (HMSIW) power divider with bandpass response and good frequency selectivity is proposed. The proposed power divider includes input/output microstrip lines, four HMSIW resonators, cross-coupling circuits, and an isolation resistor. The dual-band bandpass-filtering response is obtained by using the dual-mode slotted HMSIW. To get good frequency selectivity, the input/output cross-coupling circuits have been used, and several transmission zeros can be observed. A dual-band filtering-response HMSIW power divider is designed, fabricated and measured. The total size of the fabricated power divider is 0.58λg × 0.45λg. The measured results show a reasonable agreement with the simulated ones. The measured central operating frequencies of the dual-band HMSIW power divider are at 2.43 and 3.50 GHz, respectively. The measured 3-dB fractional bandwidth is about 13.3% and 6.3% in the two passbands, and the measured output isolation is about 20 dB.

Dual-Band Half Mode Substrate Integrated Waveguide Filter With Independently Tunable Bands

In this brief, a dual-mode dual-band filter based on half-mode substrate integrated waveguide (HMSIW) is presented. The proposed filter has the capability to tune the two pass-bands independently. The proposed filter consists of two HMSIW resonators coupled through a pair of ${E}$ -shaped coupling slots. Two resonating modes ( TE 101 and TE 102) are excited in each resonator. A varactor diode is used in the proposed filter for tuning purpose. The varactor diode is placed in the structure in such a way that both bands can be tuned independently. The lower passband can be tuned from 3.26 to 3.47 GHz with insertion loss of 0.2–2.9 dB. The higher passband can be tuned from 5.47 to 6.13 GHz with low insertion loss of 0.1–2.1 dB. The presented results show the flexibility of the filter to achieve desired responses and its suitability for integration with any tunable planar structure. A good agreement between the simulated and measured results is observed.

Compact dual‐band filter using interleaved folded half‐mode substrate integrated waveguide resonator

A multi-layer interleaved folded half-mode substrate integrated waveguide (HMSIW) dual-band filter is proposed. The TE 101 and TE 102 mode of the HMSIW resonators form dual-band response by vertical coupling, and the bandwidth of the two passbands can be independently designed by adjusting the coupling apertures. Moreover, three transmission zeros (TZs) are obtained to improve out-of-band rejection, and the TZs can be flexibly designed below or above the passband. By vertically superimposing the HMSIW cavity, the HMSIW filter can be extended to multi-pole dual-band filters. A dual-band filter with centre frequency of 3.05 and 4.7 GHz was fabricated and measured to verify the proposed method. The simulated and measured results are in good agreement.

A filter design method based on higher-order modes of fan-shaped half-mode substrate integrated waveguide resonator

A filter design method based on higher-order modes of fan-shaped half-mode substrate integrated waveguide resonator

Novel half-mode substrate integrated waveguide bandpass filters using semi-hexagonal resonators

In this paper, a novel bandpass filter is presented, designed, and implemented by using a triple mode semi-hexagonal Half-Mode Substrate Integrated Waveguide (HMSIW) cavity, which has the advantages of compact size, low insertion loss, and high selectivity in upper and lower passband. To realize a triple mode filter, the first resonant mode is shifted to near the next two modes using a via hole perturbation. Two microstrip open stubs connected to open edge of HMSIW resonator are introduced to generate two transmission zeros in the lower passband. The position of transmission zeros could be controlled by adjusting the coupling gap between the microstrip open stub resonators. By etching an E-shape slot on the top plate of HMSIW resonator, two other transmission zeros are produced in the upper passband. A wide-band planar six-pole bandpass filter, which has the advantages of wide bandwidth and small size, is also proposed and fabricated by cascading two triple mode resonators. Measured results indicate that 29% and 47% fractional bandwidth, as well as approximately 1 dB and 1.1 dB insertion loss, are achieved for the proposed filters. Measured results of all those filters agree well with the simulated results.

Compact UWB BPF with a Tunable Notched Band based on Triplemode HMSIW Resonator

A novel triple-mode resonator based on the half-mode substrate integrated waveguide (HMSIW) structure is proposed to design the ultra-wideband (UWB) filters. The UWB filter topology is given by analyzing the resonant frequencies of the three modes and the signs of the coupling between the three modes and the input/output ports. With the filter synthesis method, a triple-mode UWB filter with passband from 3.1-10.6 GHz is effectively realized with two transmission zeros at the upper stopband. To block the existing undesired narrowband radio signals in FCC UWB range, a notched band can be easily generated and controlled by a loaded stub-capacitor. For demonstration, an UWB filter with a tunable notched band from 3.7 to 7.7 GHz and compact size is designed and fabricated. Both simulated and measured results indicate that the proposed new filter has the properties of wide tuning range of the notched band and sharp roll off.

Compact Dual-band Bandpass Filter Using HMSIW Resonator and Slot Perturbation

A compact dual-band filter using half-mode substrate integrated waveguide (HMSIW) resonators is presented in this letter. Dual-band response is achieved by the quasi-TEM mode and the TE102 mode of the novel HMSIW resonator. Slotline perturbation is introduced to adjust the resonant frequency of the TE102 mode, while it has little effect on the performance of the quasi-TEM mode. Source-load coupling is utilized to obtain good selectivity and high out-of-band rejection. A dual-band filter is designed, fabricated and measured to demonstrate the proposed method. The simulated and measured results show reasonable agreement.

Substrate integrated waveguide filters and mechanical/electrical reconfigurable half-mode substrate integrated waveguide filters

In this paper, novel evanescent mode substrate integrated waveguide (SIW) and half-mode substrate integrated waveguide (HMSIW) filters are proposed, and their applications to mechanical and electrical reconfigurable bandpass filters (BPFs) are studied. SIW and HMSIW loaded with coupled complementary split-ring resonators achieve forward electromagnetic wave transmission below the waveguide cutoff frequency due to evanescent wave amplification. The half-mode configuration of the proposed SIW BPF is an opening structure, and the proposed HMSIW BPF is suitable to load with control elements. The electric/magnetic coupling effects and frequency responses reconfigurable mechanics of the proposed HMSIW structure are studied based on lumped equivalent circuit model. By using floating capacitors with mechanical switches and PIN diodes loaded on the HMSIW resonators, two one-bit HMSIW 500 MHz mechanical and 300 MHz electrical reconfigurable BPFs are demonstrated.

A Half-Mode Substrate-Integrated-Waveguide Tunable Filter Using Packaged RF MEMS Switches

A two-pole, half-mode substrate-integrated-waveguide (HMSIW) RF MEMS tunable filter with 28% tuning range around 1.4 GHz is presented. The filter occupies a total area of λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> × 0.7λg @ 1.4 GHz and exhibits an insertion loss of 1.2-3.4 dB, return loss better than 11 dB and quality factor of 75-140 for all tuning states, while having excellent linearity. The filter maintains a constant absolute 1 dB bandwidth of 85 ±10 MHz over the filter tuning range. Circuit models for the tunable HMSIW resonator and a methodology for systematic filter design are also described in detail.