Rectangular Split Ring Resonator Research Articles

Compact Ultrawide Band Metamaterial-Inspired Split Ring Resonator Structure Loaded Band Notched Antenna

A novel compact size ultrawide band planar antenna with band notched characteristics is present. The band rejection characteristic is achieved by loading a pair of metamaterial inspired rectangular split ring resonator (SRR) near the feed line and by etching the SRR slots on a radiating patch. The simulated and measured results reveal that the proposed antenna exhibits the impedance bandwidth over the ultrawide band (UWB) frequency range from 3.1 to 14 GHz with the voltage standing wave ratio less than 2 except for band stop bands at 3.29 to 3.7 GHz (WiMAX band), 3.7 to 4.10 GHz (C-band), 5.1 to 5.9 GHz (WLAN band), and 7.06 to 7.76 GHz (downlink X-band satellite communication), respectively. The proposed antenna fabricated on low-cost FR-4 substrate has compact size of 24 × 20 × 1.6 mm3. The simulation results are compared with measured results and demonstrate good agreement with stable gain over pass bands. The proposed antenna also exhibits dipole-like radiation pattern in E-plane and omni-directional pattern in H-plane. These results led to conclusion that the presented antenna is a suitable candidate for ultrawide band UWB applications with desired band notch characteristics.

Broadband folded reflectarray based on single‐layer subwavelength elements using discrete phase control

In this article, a new subwavelength element is introduced into the broadband folded reflectarray antenna (FRA). The element comprises a rectangular split-ring resonator with two slits and a square patch located in the center of the rectangular ring. It can achieve superior cross polarization conversion (CPC) performance from 16.2 to 26.4 GHz with 1 dB bandwidth of 45.4%, and high orthogonal polarization isolation. Furthermore, changing the positions of two splits of the element can achieve two discrete reflection phases (0° and 180°) with the high CPC efficiency and angular stability. To verify the feasibility, an FRA using the digitally quantized phase distribution method is designed and measured at 22 GHz. The measured results show that the 1 dB gain bandwidth of the proposed FRA is 30.8%, and the maximum aperture efficiency is 15.4%. This superior performance is comparable with the existing FRAs.

Compact Low-Cost Filter for 5G Interference Reduction in UHF Broadcasting Band

The allocation of part of the UHF band to 4G and 5G services has generated the appearance of channel interferences over the digital terrestrial television frequency band. In order to reduce these interferences, this work presents a novel and efficient band-stop filter implemented using microstrip technology. The filter, designed with rectangular split-ring resonators etched in the ground plane, provides a cutoff frequency above channel 48 (694 MHz), a high roll-off rate of 44 dB in 56 MHz and a rejection bandwidth of 250 MHz that covers the upper UHF band occupied by 4G and 5G with rejection levels close to 35 dB. The filter is manufactured entirely over a printed circuit board without lumped elements to reduce production costs, fine tuning after the assembly stage and maintenance. Moreover, it presents a compact subwavelength size of only 0.07 λ × 0.17 λ to facilitate installation, whether at the input of the TV terminal or integrated with the balun at the rooftop antenna.

A thermal-insensitive ultra-broadband metamaterial absorber

In this paper, a thermal-insensitive ultra-broadband metamaterial absorber (MMA) based on indium tin oxide (ITO) patterns and the SiO2 dielectric substrate is proposed to demonstrate high-temperature stability and excellent absorbability. The surface patterns consist of two different sizes of rectangular split-ring resonators with two gaps in each split-ring. Results from simulation indicate that at the initial temperature of 300 K, the relative absorption bandwidth reaches 83.35%, and the spectrum with absorptivity higher than 90% ranges from 8.00 GHz to 19.43 GHz. Moreover, in the temperature range of 300–700 K, the effective bands remain steady and cover more than 95% of the initial band. The simulation results also verify that the performance of MMA remains stable when exposed to high-intensity incident and high temperature of 500 K. The analysis of the surface current, electromagnetic (EM) field, power-loss density, equivalent circuit, and constitutive EM parameters reveals the mechanisms of thermal-insensitive ultra-broadband. This study expands potential applications of MMAs in conditions with thermal-stable demands.

Tunable terahertz metamaterial using electrostatically electric split-ring resonator

A design of electrostatically tunable metamaterial is proposed in the terahertz (THz) frequency range using electric split-ring resonators (eSRR), which shows polarization-dependent and switching characteristics. The eSRR is composed of anchored rectangular split-ring resonators and a movable middle I-shaped metal bar. By exploiting electrostatic force to change the gap within eSRR and the distance of middle I-shaped metal bar, the electromagnetic characteristics of eSRR can be controlled. The electromagnetic response of eSRR shows a single-resonance in transverse electric (TE) mode and keeps as quite stable. In transverse magnetic (TM) mode, the electromagnetic response of eSRR shows dual- and triple-resonance. Such eSRR design is able to be used in lots of applications, such as polarizers, actively tunable filters, frequency-selective detectors, tunable high-efficiency sensors, and multi-functional switches in the THz optoelectronic devices.

Multiband linear and circular polarization rotating metasurface based on multiple plasmonic resonances for C, X and K band applications

In this work, a multiband polarization converting metasurface is presented which achieves cross-polarization conversion in five frequency bands while linear-to-circular and circular-to-linear polarization transformation in eight frequency bands. The polarization transforming functionality of the structure is spread over an ultra-wide frequency range (5–37 GHz) covering most of X, C, Ku, K and Ka bands. Such an extraordinary ultra-wideband operation originates from multiple plasmonic resonances occurring in the structure based on two coupled rectangular split-ring resonators. Moreover, the polarization transforming capability is stable within the frequency range 5–19 GHz for wide oblique incidence angles, which is up to 60°, both for transverse-electric and transverse-magnetic polarizations. Furthermore, the proposed structure acts as a meta-mirror which preserves handedness of the circular polarization upon reflection. Measurements performed on the fabricated metasurface are found to be consistent with numerical simulation results. The ability to perform three functionalities through a single compact structure with extraordinary wideband, qualifies the proposed design to be a promising candidate for integration with important microwave applications such as satellite, radar, and 5G communication.

Split-Ring Resonator-Loaded Baffles for Decoupling of Dual-Polarized Base Station Array

Baffles loaded by split-ring resonator (SRR) are proposed to reduce the mutual coupling for ±45° dual-polarized multiple-input–multiple-output (MIMO) antenna. Each baffle consists of two rectangular SRR printed on one side of a 1 mm FR4 substrate. The final decoupling structure contains four baffles forming a barrier wall that reduces the coupling over the 5G band of 3.4–3.8 GHz. Dual-polarized cross-dipole array with SRR loading baffles is simulated and measured to demonstrate their effectiveness in the coupling reduction. The results show that the mutual coupling can be effectively reduced below −25 dB over the entire bandwidth while maintaining a compact array.

Broadband circularly polarized printed falcate‐shaped monopole antenna

In this study, a simple broadband circularly polarized (CP) printed monopole antenna for S/C-band applications is proposed. The CP antenna is composed of a falcate-shaped monopole with a right-angle trapezoid stub, then wide impedance and axial ratio (AR) bandwidths are achieved. By placing one rectangular split-ring resonator above the stub for generating upper CP mode, both of impedance and CP performances are further improved. The proposed antenna is fabricated on a FR4 substrate and measured. The measured −10-dB impedance bandwidth is 107%, ranging from 2.4-7.9 GHz, and the measured 3-dB AR bandwidth is 94% (2.4-6.6 GHz), covering the entire wireless local area network (WLAN) and WiMAX bands.

Applications of Fourth-Layered Rectangular Split Ring Resonator of Swastika-Shaped Metamaterial Unit Cell

Applications of Fourth-Layered Rectangular Split Ring Resonator of Swastika-Shaped Metamaterial Unit Cell - written by Rahul Ateriya , Garima Tiwari published on 2020/08/05 download full article with reference data and citations

Analysis and design of a compact ultra-wideband antenna with WLAN and X-band satellite notch

<span lang="EN-US">A compact design of ultra-wideband (UWB) antenna with dual band-notched characteristics based on split-ring resonators (SRR) are investigated in this paper. The wider impedance bandwidth (from 2.73 to 11.34 GHz) is obtained by using two symmetrical slits in the radiating patch and another slit in the partial ground plane. The dual band-notch rejection at WLAN and X-band downlink satellite communication system are obtained by inserting a modified U-strip on the radiating patch at 5.5 GHz and embedding a pair of rectangular SRRs on both sides of the microstrip feed line at 7.5 GHz, respectively. The proposed antenna is simulated and tested using CST MWS high frequency simulator and exhibits the advantages of compact size, simple design and each notched frequency band can be controlled independently by using the SRR geometrical parameters. Therefore, the parametric study is carried out to understand the mutual coupling between the dual band-notched elements. To validate simulation results of our design, a prototype is fabricated and good agreement is achieved between measurement and simulation. Furthermore, a radiation patterns, satisfactory gain, current distribution and VSWR result at the notched frequencies make the proposed antenna a suitable candidate for practical UWB applications.</span>

Dual split resonator lowpass filter with ultra‐wide stopband and sharp roll‐off rate

A novel microstrip lowpass filter design using rectangular split-ring resonators with dual splits are designed, analysed, and fabricated with exceptional performance such as ultra-wide stopband and sharp roll-off rate along with its compactness. The symmetrical suppressing cells are also employed to reject higher-order harmonics from the stopband without affecting selectivity. The expression for transmission zero of dual split resonator-1 is extracted from the equivalent circuit analysis and observed the significance of coupling. A sharp roll-off performance of 224 dB/GHz and relative stopband width of 161% are achieved with a cut-off frequency of 2.9 GHz.

A Quad Band Metamaterial Miniaturized Antenna for Wireless Applications with Gain Enhancement

This paper presents a designing of dual-coated miniaturized metamaterial inspired quad band antenna for wireless standards with gain enhancement. Proposed design has compactness in size with electrical dimension of 0.239 × 0.351 × 0.0127 λ (30 × 44 × 1.6 mm3), at lower frequency of 2.39 GHz. The antenna consist a double printed slotted hexagonal shape radiating section with implementation of metamaterial rectangular split ring resonator. Antenna achieve quad bands for wireless standards WLAN (2.4/5.8 GHz), WiMAX (3.5 GHz), IEEE 802.11P (WAVE-5.9 GHz), ITU assigned X bands (7.25–7.75, 7.9–8.4 GHz) and satellite communication systems operating bands (C-band: 7.4–8.9 GHz and X-band: 8–10 GHz for satellite TV). An acceptable gain, stable radiation characteristics and good impedance matching are observed at all the resonant frequencies of the proposed structure. By application of proposed frequency selective surface an average enhancement of gain is about 4–5 dB over the operating band. Antenna fabricated and tested represent good agreement between the simulated and measured results.

Design of compact wideband 90° Schiffman phase shifter incorporating CSRR

ABSTRACTIn this work, a compact and wideband Schiffman phase shifter is proposed using a microstrip transmission line. This proposed phase shifter incorporates a rectangular complementary split-ring resonator (CSRR) and two open stubs. It is designed to get a phase shift of 90° with ±5° phase imbalance for the frequency range of 1.47–3.52 GHz. It shows a fractional bandwidth of 85.41% at the center frequency of 2.4 GHz. The proposed design occupied a total area of 0.067 λg2. The proposed structure is fabricated and validated, there is a good agreement between the simulated and measured results.

A novel miniature coplanar band-pass filter for ISM applications

This paper presents a novel approach to design a compact miniature coplanar band-pass filter by using rectangular split ring resonator. This proposed circuit is designed for the Industrial, Scientific and, Medical (ISM) frequency band applications at 2.4 GHz. At the first stage, a metamaterial resonator is designed and simulated in a TEM waveguide to verifiy its electromagnetic proprieties around the desired frequency bands. At the second stage, a band pass filter is designed using the proposed metamaterial resonator. Many parametric studies are realized to investigate the effect and influence of some resonator parameters on the proposed BPF performances. ADS Agilent and CST-MWS solvers are used in order to verify the simulated results. The circuit frequency responses show an excellent insertion loss and good return loss in the passband.

Wideband circularly polarized parasitic patches loaded coplanar waveguide-fed square slot antenna with grounded strips and slots for wireless communication systems

In this paper, the design, implementation, and experimental validation of a wideband circularly polarized square slot antenna (CPSSA) is presented. The proposed antenna comprises of an irregular square patch, asymmetrical grounded-L strips, an inverted-L grounded slot, a parasitic asymmetrical rectangular split ring resonator (RSRR) and inverted-L strip patches with the overall size of 0.305λL × 0.305λL × 0.007λL. By appropriately embedding strips, slots and parasitic patches on the antenna structure, the measured wideband 3-dB axial ratio bandwidth (ARBW) of 83.2% (2.33–5.65 GHz) is obtained, while the measured impedance bandwidth (IBW) of 86.72% (2.165–5.48 GHz) is achieved. Overall, CP bandwidth is 80.66%. A parametric study of different design parameters is investigated, and the overall performance of the antenna is presented.

Embroidered Rectangular Split-Ring Resonators for the Characterization of Dielectric Materials

In this paper, we report an embroidered rectangular split-ring resonator (SRR) operating at S band for material characterization based on the differences in dielectric parameters. We designed, fabricated and characterized SRR sensors on a conventional fabric that can be conformally attached over the surface of samples under investigation. The structures are made of conductive threads and can be embroidered on any dielectric fabric at low cost using conventional embroidery methods. We have demonstrated material characterization capability of the sensors using a specific design with a length of 60 mm and a width of 30 mm. We wrapped the sensors on low-density polyethylene (LDPE) bottles filled with deionized (DI) water and common solvents (ethanol, methanol, isopropanol and acetone) in our experiments. We measured the nominal resonant frequency of a specific sensor wrapped around an empty bottle as 2.07 GHz. The shifts in resonant frequencies when the bottle was filled with the solvents follow the dielectric constants of the solvents.

Implementation of Metamaterial Loading to Miniaturized UWB Dipole Antenna for WLAN and WiMAX Applications with Tunability Characteristics

This paper presents a double-printed circular slot inscribed, hexagonal shape miniaturized dipole antenna featuring the ultra-wideband (UWB) characteristics with the implementation of linearly tapered feedline. The miniaturized UWB dipole antenna is designed for wireless applications wireless local area network (WLAN) and WiMAX by introducing a proposed metamaterial unit cell. Further, in comparison with the conventional UWB dipole antenna, miniaturization is achieved up to 35.89% and 16.67% with respective active patch area and antenna volume, respectively. The electrical dimension of the proposed antenna is 0.299 λ × 0.4385 λ × 0.0159 λ, of course, at lower frequency of 2.99 GHz. The use of metamaterial rectangular split-ring resonator and slotted ground structure witnessed the band achievements for wireless standards WLAN and WiMAX. The proposed structure is fabricated on FR4 substrate and tested. Impedance bandwidth of proposed antenna is obtained about 7.26% (2.39–2.57 GHz), 25.23% (2.91–3.75 GHz), and 16.92% (4.87–5.77 GHz) under simulation and 11.49% (2.38–2.67 GHz), 24.48% (2.94–3.76 GHz), and 15.99% (4.95–5.81 GHz) in measurement for WLAN (2.4–2.5, 5.150–5.250, and 5.725–5.825 GHz) and WiMAX (3.3–3.8 GHz) bands, respectively. Tunability between the wireless standards is demonstrated with the help of PIN diodes. The proposed design achieved high average gain of 3.31 and 2.06 dBi for simulation and measurement, respectively. The peak average radiation efficiency of 82.9% is observed during measurement mode. Experimental results are in good agreement with those obtained in the simulation of the proposed antenna.

An integrated MIMO filtenna with wide band-narrow band functionality

In this literature an integrated multiple-input-multiple-output (MIMO) filtenna for both Wideband (WB)-Narrowband (NB) functionality is investigated. The approach to the design involves a two element, dual mode MIMO antenna system. In wideband mode two identical circular radiators are used while a pair of rectangular split ring resonator (RSRR) based band pass filters integrated in to the WB antennas are used in narrowband mode. The ground plane is extended in the shape of T shaped stub for the shake of isolation improvement between the ports. All the scattering parameters (S11/S22, S12/S21) of the fabricated antenna prototype are verified in both simulation and measurement for the determination of better antenna performance. Here, a wide impedance bandwidth of 1.2–6 GHz is achieved during wideband mode of operation whereas a frequency response of 3.3–4.0 GHz is found in narrowband mode with isolation in both the cases less than −25 dB and −30 dB respectively. Moreover the performance parameters of MIMO antenna system such as envelope correlation coefficient (ECC), diversity gain (DG) and mean effective gain (MEG) are also evaluated using S matrix to strengthen the design concept.

Dual terahertz slow light plateaus in bilayer asymmetric metasurfaces

This work theoretically proposed dual terahertz (THz) slow light plateaus by tuning the destructive interference between a toroidal magnetic momentum and magnetic dipole momentum. The metasurfaces are in a sandwich structure. A metallic cut-wire is patterned on one side of polyimide thin-film, and a rectangular split-ring resonator (SRR) on the other side with asymmetric layout. By translating the SRR along the cut-wire from the top terminal to the bottom terminal of the cut-wire, dual slow light plateaus are found in the transparency window at a certain range of displacement. A maximum of 40.4 ps group delay is achieved as the displacement achieves 9 μm. The numerical mapping of electromagnetic field indicates that the electrical dipole on metallic cut-wire results in a localized toroidal magnetic momentum, while the inductive-capacitor oscillation of SRR results in a magnetic dipole momentum. These two momentums have opposite directions, which will repel each other at certain displacement, creating the transparency windows. Furthermore, an electrical coupling takes place in between the bilayer metasurface so that the slow light achieves a maximum, with the aforementioned two mechanisms working in coincidence.

A Novel SWB Antenna with Triple Band-Notches Based on Elliptical Slot and Rectangular Split Ring Resonators

In this paper, a wideband antenna was designed for super-wideband (SWB) applications. The proposed antenna was fed with a rectangular tapered microstrip feed line, which operated over a SWB frequency range (1.42 GHz to 50 GHz). The antenna was implemented at a compact size with electrical dimensions of 0.16 λ × 0.27 λ × 0.0047 λ mm3, where λ was with respect to the lowest resonance frequency. The proposed antenna prototype was fabricated on a F4B substrate, which had a permittivity of 2.65 and 1 mm thickness. The SWB antenna exhibited an impedance bandwidth of 189% and a bandwidth ratio of 35.2:1. Additionally, the proposed antenna design exhibited three band notch characteristics that were necessary to eradicate interference from WLAN, WiMAX, and X bands in the SWB range. One notch was achieved by etching an elliptical split ring resonator (ESRR) in the radiator and the other two notches were achieved by placing rectangular split ring resonators close to the signal line. The first notch was tuned by incorporating a varactor diode into the ESRR. The prototype was experimentally validated with, with notch and without notch characteristics for SWB applications. The experimental results showed good agreement with simulated results.