Circular Split Ring Resonator Research Articles

Wireless image transfer by various antennas using transmitter and receiver modules at 5.8 GHz

Abstract This research proposes an inexpensive technique for wireless image transfer for security and surveillance applications. The technique uses a 5.8 GHz transmitter and receiver module, along with external antennas in the real-time image transfer within a radius of 100 m. The transferred images are stored in a laptop using a Python code-based graphical user interface application. Different antennas, dipole, circular split-ring resonators, hexagonal split-ring resonators, and metamaterial antennas are utilized for comparison. The Blind/Referenceless Image Spatial Quality Evaluator method is used to assess the picture quality of transferred images to quantify image transfer performance when no ground truth or reference photos are supplied. According to the presented results, images transferred using metamaterial antennas have higher quality than those transferred with other types of antennas. For security considerations, such a system can communicate and store the images in real time.

Investigation of circularly polarized MIMO antenna with enhanced isolation for sub-6 GHz application

This article demonstrates the design process for a unique, two-port, circularly polarized (CP) multiple input multiple outputs (MIMO) antenna for fifth-generation (5G) applications operating at sub-6 GHz. The proposed 2-port CP MIMO antenna comprises a patch antenna with a distinctive slot and a circular split ring resonator (SRR) at the ground plane. The circular patch antenna’s resonant frequency is moved to a lower frequency by the addition of a circular SRR at the ground plane. Investigating a special slot at the patch antenna can help in the enhancement of circular polarization and bandwidth. A sequence of parasitic elements in the shape of ‘h’ is placed in the space between the two antenna elements for decoupling. The minimum 20 dB inter isolation among the antenna elements in the proposed 2-port CP MIMO antenna’s operating band is made possible by these h-shaped parasitic elements. In addition, to ensure the proposed antenna is more reliable for 5G applications at sub-6 GHz, other diversity parameters including Envelop Correlation Co-efficient (ECC), Mean Effective Gain (MEG), Diversity Gain (DG), TARC (Total Active Reflection Co-efficient) and CCL (channel capacity loss) are also calculated . In comparison to existing MIMO systems of the same order, the proposed 2-port CP MIMO antenna appears to have the minimum channel capacity loss and excellent diversity performance. The proposed 2-port CP MIMO antenna achieves an impedance bandwidth of 3.3 to 3.6 GHz with impedance matching better than 10 dB and has an axial ratio bandwidth of 3.35 to 3.51 GHz with a steady radiation pattern in both planes over the operating frequency bands.

Green Wearable Sensors and Antennas for Bio-Medicine, Green Internet of Things, Energy Harvesting, and Communication Systems.

This paper presents innovations in green electronic and computing technologies. The importance and the status of the main subjects in green electronic and computing technologies are presented in this paper. In the last semicentennial, the planet suffered from rapid changes in climate. The planet is suffering from increasingly wild storms, hurricanes, typhoons, hard droughts, increases in seawater height, floods, seawater acidification, decreases in groundwater reserves, and increases in global temperatures. These climate changes may be irreversible if companies, organizations, governments, and individuals do not act daily and rapidly to save the planet. Unfortunately, the continuous growth in the number of computing devices, cellular devices, smartphones, and other smart devices over the last fifty years has resulted in a rapid increase in climate change. It is severely crucial to design energy-efficient "green" technologies and devices. Toxic waste from computing and cellular devices is rapidly filling up landfills and increasing air and water pollution. This electronic waste contains hazardous and toxic materials that pollute the environment and affect our health. Green computing and electronic engineering are employed to address this climate disaster. The development of green materials, green energy, waste, and recycling are the major objectives in innovation and research in green computing and electronics technologies. Energy-harvesting technologies can be used to produce and store green energy. Wearable active sensors and metamaterial antennas with circular split ring resonators (CSSRs) containing energy-harvesting units are presented in this paper. The measured bandwidth of the matched sensor is around 65% for VSWR, which is better than 3:1. The sensor gain is 14.1 dB at 2.62 GHz. A wideband 0.4 GHz to 6.4 GHz slot antenna with an RF energy-harvesting unit is presented in this paper. The Skyworks Schottky diode, SMS-7630, was used as the rectifier diode in the harvesting unit. If we transmit 20 dBm of RF power from a transmitting antenna that is located 0.2 m from the harvesting slot antenna at 2.4 GHz, the output voltage at the output port of the harvesting unit will be around 1 V. The power conversion efficiency of the metamaterial antenna dipole with metallic strips is around 75%. Wearable sensors with energy-harvesting units provide efficient, low-cost healthcare services that contribute to a green environment and minimize energy consumption. The measurement process and setups of wearable sensors are presented in this paper.

Enhancing connectivity/mobility in WBAN applications through detachable wearable multi-band MIMO antenna

The connectivity and mobility of a miniaturized multi-band four-port textile leaky wave multiple-input multiple-output (MIMO) antenna designed on a layer of denim (εr = 1.6, tanδ = 0.006) is enhanced by integrating it with two detachable spiral buttons designed on circular PTFE substrate (εr = 2.1, tanδ = 0.001). The connectivity and mobility enhancement of the proposed antenna is evaluated in terms of radiation and diversity parameters. Nested hexagonal split rings behind the buttons, U-shaped slots on textiles, a comb-shaped neutralization network, and an aperture-coupled feed technique are utilized. The unique structure of the buttons on a rigid substrate and the leaky wave antenna on the textile and their integration, the periodic nested elliptical and circular split ring resonators (CSRRs) slots on the aperture coupled to ground, are to expand the connectivity and mobility of the proposed MIMO antenna by offering multiple bands, higher isolation, broadside radiation, and low specific absorption rate (SAR). The leaky wave and button antennas have dimensions of 40 × 30 × 1 mm3 and a diameter of only 13 mm, respectively. The operational bands are 0.86–2.75 GHz, 2.9–4.85 GHz, 5.75–6.15 GHz, and 8–9.85 GHz, covering the L, C, S, and X bands. Additionally, diversity performance is evaluated by defining the envelope correlation coefficient (ECC), diversity gain (DG), Channel Capacity Loss (CCL), and mean effective gain (MEG). The simulation and measurement findings are in good agreement. Following that, it offers a maximum gain of 8.25 dBi, low SAR (<0.05), an ECC below 0.05, DG above 9.85 dB, CCL< 0.25 bits/s/Hz, MEG <−3 dB, Circular polarization (CP), and strong isolation (>22 dB) between every two ports. These features make the proposed antenna an ideal option for MIMO communications and suitable for wireless local area network (WLAN) and fifth-generation (5G) communications.

Compact metamaterial-based single/double-negative/near-zero index resonator for 5G sub-6 GHz wireless applications

The concept, performance, and analyses of distinctive, miniaturized metamaterial (MTM) unit cell addressing the forthcoming Sub 6 GHz 5G applications are presented in this paper. Two circular split-ring resonators (CSRR) with two parallel rectangular copper elements in front of the design and a slotted square element in the background make up the suggested metamaterial. It has a line segment with tunable features that is positioned in the center of the little ring copper structure. The suggested design offers a significant operating frequency band of 220 MHz together with a resonance of transmission coefficient S21 at 3.5 GHz. Furthermore, in two (z & x) principal axes of wave propagation, wide-range achievement, single/double-negative (S/DNG) refractive index, negative permittivity, and near-zero permeability properties were demonstrated. Through varying central slotted-strip line length, resonance frequencies can be selectively altered. Moreover, the metamaterial has overall dimensions of 9 × 9 mm2 and is composed on a Rogers 5880 RT substrate. In order to create the suggested MTM's equivalent circuit, which shows similar coefficient of transmission (S21), a proposed design’s numerical simulation is carried out in the CST micro-wave studio. This simulation is after that put to comparison with manufacturing of the design.

Left-handed metamaterial based on circular split ring (CSRR) resonator for microwave sensing Application

This paper presents a new metamaterial structure specifically designed to operate in the L, S, and C frequency bands. It is characterized by a small unit cell size of 15mm × 15 mm. The metamaterial's electromagnetic properties are thoroughly examined, utilizing FR-4 substrate material and copper circular split ring resonators (CSRRs). The Computer Simulation Technology (CST) software uses the finite integration technique (FIT) to precisely model the effective parameters over a frequency range of 0–6 GHz. In simulations and experiments, the structure demonstrates negative refractive index, effective permittivity, and effective permeability. The electric and magnetic field distributions within the unit cell are accurately characterized using vector fields. In addition, the equivalent circuit is simulated and depicted using ADS software, with comparisons drawn between the measured data and the simulated data. The experimental validation, conducted using six varying thicknesses of FR4 materials, verifies the resemblance between the simulated and the measured transmission coefficients. Moreover, the effective medium ratio (EMR) of the metamaterial is calculated to be 12.74, indicating its promising capabilities for microwave sensing applications. The examination of the sensor model uncovers such metrics as quality factors, frequency detection resolution (FDR) values, and sensitivities, all of which enhance our comprehension of the material's performance. This discovery has the potential to advance the development of sensing metamaterials, which could significantly impact various applications and enhance research in the field.

Coplanar Waveguide (CPW) Loaded with Symmetric Circular and Polygonal Split-Ring Resonator (SRR) Shapes

This paper investigates the performance of coplanar waveguide (CPW) structures loaded with symmetric circular and polygonal split-ring resonators (SRRs) for microwave and RF applications, leveraging their unique electromagnetic properties. These properties make them suitable for metamaterials, sensors, filters, resonators, antennas, and communication systems. The objectives of this study are to analyze the impact of different SRR shapes on the transmission characteristics of CPWs and to explore their potential for realizing compact and efficient microwave components. The CPW-SRR structures are fabricated on a dielectric substrate, and their transmission properties and spectrogram are experimentally characterized in the frequency range of 4 GHz to 10 GHz with the rotation angles of the SRR gap. The simulation results demonstrate that the resonant frequencies and magnitude of the transmission coefficient of the CPW-SRR structures are influenced by the geometry of the SRR shapes and the rotation angles of the SRR gap, with certain shapes exhibiting enhanced performance characteristics compared to others. Moreover, the symmetric circular and polygonal SRRs offer design flexibility and enable the realization of miniaturized microwave components with improved performance metrics. Overall, this study provides valuable insights into the design and optimization of CPW-based microwave circuits utilizing symmetric SRR shapes, paving the way for advancements in the miniaturization and integration of RF systems.

Broadband high-efficiency plasmonic metalens with negative dispersion characteristic

Controlling the dispersion characteristic of metasurfaces (or metalenses) along a broad bandwidth is of great importance to develop high-performance broadband metadevices. Different from traditional lenses that rely on the material refractive index along the light trajectory, metasurfaces or metalenses provide a new regime of dispersion control via a sub-wavelength metastructure, which is known as negative chromatic dispersion. However, broadband metalenses design with high-performance focusing especially with a reduced device dimension is a significant challenge in society. Here, we design, fabricate, and demonstrate a broadband high-performance diffractive-type plasmonic metalens based on a circular split-ring resonator metasurface with a relative working bandwidth of 28.6%. The metalens thickness is only 0.09λ0 ( λ0 is at the central wavelength), which is much thinner than previous broadband all-dielectric metalenses. The full-wave simulation results show that both high transmissive efficiency above 80% (the maximum is even above 90%) and high average focusing efficiency above 45% (the maximum is 56%) are achieved within the entire working bandwidth of 9–12 GHz. Moreover, an average high numerical aperture of 0.7 ( NA=0.7 ) of high-efficiency microwave metalens is obtained in the simulations. The broadband high-performance metalens is also fabricated and experimental measurements verify its much higher average focusing efficiency of 55% (the maximum is above 65% within the broad bandwidth) and a moderate high NA of 0.6. The proposed plasmonic metalens can facilitate the development of wavelength-dependent broadband diffractive devices and is also meaningful to further studies on arbitrary dispersion control in diffractive optics based on plasmonic metasurfaces.

An Analysis of Split-Ring Resonators and Potential Barcode Application

This paper presents an analysis of various split-ring resonator (SRR) configurations coupled with coplanar waveguides (CPW). Three distinct resonant structures are presented, namely, the S-shaped split-ring resonator (S-SRR), the conventional split-ring resonator (SRR), and a pair of SRR. Among the examined resonant structures, it is observed that the S-SRR exhibits the smallest electrical size with the corresponding resonant frequency of 1.37 GHz, while the conventional SRR has the largest electrical size with the corresponding resonant frequency of 3.34 GHz. On the other hand, the resonant frequency of a dual SRR is 2.37 GHz. However, the transmission coefficient of a dual SRR is -11.43 dB, which is higher than S-SRR (-10.02 dB) and SRR (-8.18 dB). Furthermore, this study extends the analysis between a square dual SRR and a circular dual SRR with retained area. The square SRR demonstrates a lower resonance frequency (2.23 GHz) relative to its circular counterpart (2.37 GHz). The comparison also shows that the transmission coefficient of the square configuration is -13.88 dB, which is higher than its circular counterpart (-11.43 dB). The realization of a barcode application is achieved by loading multiple S-shaped split ring resonators (S-SRRs) with varying geometric parameters adjacently onto the transmission line. By individually rotating each of these S-SRRs, it becomes possible to alter the notch magnitude, thereby positioning it within a specific designated range corresponding to a particular code. In the case of a configuration involving rotations of (0°, 45°, 90°, 0°, 45°, 90°), this approach results in the creation of a barcode denoted as "100 010 000 100 011 000". This methodology enables the encoding of information in the form of distinctive resonant responses, providing a versatile and compact means of realizing barcode applications.

Compact terahertz harmonic generation in the Reststrahlenband using a graphene-embedded metallic split ring resonator array

Harmonic generation is a result of a strong non-linear interaction between light and matter. It is a key technology for optics, as it allows the conversion of optical signals to higher frequencies. Owing to its intrinsically large and electrically tunable non-linear optical response, graphene has been used for high harmonic generation but, until now, only at frequencies < 2 THz, and with high-power ultrafast table-top lasers or accelerator-based structures. Here, we demonstrate third harmonic generation at 9.63 THz by optically pumping single-layer graphene, coupled to a circular split ring resonator (CSRR) array, with a 3.21 THz frequency quantum cascade laser (QCL). Combined with the high graphene nonlinearity, the mode confinement provided by the optically-pumped CSRR enhances the pump power density as well as that at the third harmonic, permitting harmonic generation. This approach enables potential access to a frequency range (6-12 THz) where compact sources remain difficult to obtain, owing to the Reststrahlenband of typical III-V semiconductors.

Dual circular complementary split ring resonator based metamaterial sensor with high sensitivity and quality factor for textile material detection

In this paper, a novel metamaterial sensor with excellent sensitivity and quality factor for microwave sensing applications is presented. The designed metamaterial sensor is assembled on a 1.575 mm thickness of low-cost dielectric substrate material (Rogers RT5880), and the copper is used as a resonator. Computer Simulation Technology version 2019 (CST-2019) software is employed to design and analyze the proposed metamaterial sensor. In addition, the Advanced Design System version 2016 (ADS 2016) software is used to validate the CST simulated model. Subsequently, the simulated results were validated using laboratory measurements. The optimized cell is small; its dimension is 10 × 10 mm2, and the obtained resonances are 3.85 and 6.85 GHz with notches of −26.29 and −40.03 dB, respectively. The textile material is detected by the resonance frequency change, and this frequency is dependent on the material’s permittivity values. To test the developed sensor’s sensing capabilities, three types of textiles—wool, fleece, and denim—are used. The effective medium ratio, sensitivity, and Q-factor of the structure are evaluated, and the obtained values are 8.96, 14.57%, and 345, respectively. The sensor for detecting textile materials works in the S and C bands. The resonances are shifted 530 MHz between the air and wool, 420 MHz between the air and fleece, and 640 MHz between the air and denim. The simulated outcomes and laboratory results almost matched. The projected sensor can be employed in the apparel sector to identify textile materials because it is small, inexpensive, has a high quality factor, and has high sensitivity.

Novel Meta-Fractal Wearable Sensors and Antennas for Medical, Communication, 5G, and IoT Applications

Future communication, 5G, medical, and IoT systems need compact, green, efficient wideband sensors, and antennas. Novel linear and dual-polarized antennas for 5G, 6G, medical devices, Internet of Things (IoT) systems, and healthcare monitoring sensors are presented in this paper. One of the major goals in the evaluation of medical, 5G, and smart wireless communication devices is the development of efficient, compact, low-cost antennas and sensors. Moreover, passive and active sensors may be self-powered by connecting an energy-harvesting unit to the antenna to collect electromagnetic radiation and charge the wearable sensor battery. Wearable sensors and antennas can be employed in smart grid applications that provide communication between neighbors, localized management, bidirectional power transfer, and effective demand response. A low-cost wearable antenna may be developed by etching the printed feed and matching the network on the same substrate in the printed antenna. Active modules may be placed on the same dielectric board. The antenna design parameters and a comparison between the computation and measured electrical performance of the antennas are presented in this paper. The electrical characteristics of the new compact antennas in the vicinity of the patient’s body were simulated by using electromagnetic simulation techniques. Fractal and metamaterial efficient antennas and sensors were evaluated to maximize the electrical characteristics of smart communication and medical devices. The dual- and circularly polarized antennas developed in this paper are crucial to the evaluation of wideband and multiband compact 5G, 6G, and IoT advanced systems. The new efficient sensors and antennas maximize the system’s dynamic range and electrical characteristics. The new efficient wearable antennas and sensors are compact, wideband, and low-cost. The operating resonant frequency of the metamaterial antennas with circular split-ring resonators (CSRRs) may be 5% to 9% lower than the resonant frequency of the sensor without CSRRs. The directivity and gain of the metamaterial fractal antennas with CSRRs may be up to 3 dB higher than the antennas without CSRRs. The directivity and gain of the metamaterial fractal passive sensors with CSRRs may be up to 8.5 dBi. This study presents new wideband active meta-fractal antennas and sensors. The bandwidth of the new sensors is around 9% to 20%. At 2.83 GHz, the receiving active sensor gain is 13.5 dB and drops to 8 dB at 3.2 GHz. The receiving module noise figure with TAV541 LNA is around 1dB.

Dual-band terahertz metamaterials with electromagnetically induced transparency-like enabling high-performance sensing

In this paper, a high-performance metamaterial sensor with a square split-ring resonator and a double circular split-ring resonator is proposed, which can simultaneously excite broad-band and narrow-band electromagnetically induced transparency-like (EIT-like) effects in the terahertz band. First, the mechanisms of the dual-band EIT-like effects have been revealed by the analyses of the transmission spectra and surface current distributions in the metamaterial. Then, the influences of structural parameters on the dual-band EIT-like are discussed further. Finally, the metamaterial is very sensitive to the change of the refractive index of the surrounding media, and the sensitivity of the dual-band EIT-like resonances can reach 150 GHz/RIU and 237.5 GHz/RIU and the quality factor values are 1.67 and 7.92, respectively. The proposed metamaterial broadens the pathway for the excitation of multi-band EIT-like effects and offers promising applications in multi-frequency sensors, filters and many other aspects.

Circular split ring resonator (SRR) slot and ground stub based slotted circular ultra-wideband MIMO antenna with WLAN band exclusion and high isolation performance

Circular split ring resonator (SRR) slot and ground stub based slotted circular ultra-wideband MIMO antenna with WLAN band exclusion and high isolation performance

Tunable asymmetric square split ring resonator based triple band metamaterial absorber for wireless communication system

This article presents a triple band square split ring with double circular split ring resonator incident angle-insensitive perfect metamaterial absorber. The MMA unit cell was manufactured using a FR4 substrate that had dimensions of 8 mm by 8 mm. With the flexibility of on-design adjusting of the highest absorption frequencies, the suggested MA displays peak absorption of 99.67 %, 99.85 %, and 99.97 % at 2.52 GHz, 6.99 GHz, and 9.28 GHz, correspondingly. The tuning metallic two circular split rings and square split ring resonator provide the possibility of frequency modification throughout three distinct frequency ranges: the first frequency range extends from 2.45 GHz to 2.53 GHz, the second frequency range extends from 6.91 GHz to 7 GHz, and the third frequency range extends from 8.85 GHz to 10.32 GHz. Furthermore, the suggested MA displays near-zero absorption at an oblique incidence angle of up to 45° for both the TE as well as TM modes. The unit cell demonstrates single negative properties, such as an effective medium ratio (EMR) of 14.88 and a quality factor (Q factor) that is more than 30 for both the TM mode as well as the TE mode. An equivalent circuit successfully demonstrated its performance capability, which indicated that it would create an MMA of good quality when using ADS software. A comparison between the measured results of the suggested MMA and the simulated one reveals that there is a significant amount of a similarity between both of them. Because of its easy design within small dimension, wide angular stability, strong absorption, good EMR, and flexibility to frequency tuning is suitable for a wide range of wireless communication system, especially satellite applications like electromagnetic interference reduction, radar systems, imaging, and stealth technology.

Optimization of a wideband antipodal Vivaldi antenna with metalenses

Abstract A wideband antipodal Vivaldi antenna has been designed and optimized. A slight improvement is obtained by employing multiple metalense based on circular split-ring resonators to maximize the antenna gain with the maximum bandwidth. The designed antennas have been fabricated and characterized, showing good agreement with simulations. The maximum measured gain is $G = 12\;{\textrm{dB}}$ , and the −10 dB bandwidth is from $f = 3\;{\textrm{GHz}}$ to $f = 13\;{\textrm{GHz}}$ .

Compact SCSRR‐based quad‐band antenna for Bluetooth, WiMAX, WLAN, and fixed‐satellite services

SummaryThis research describes the detailed analysis and design of the compact complex‐free structural metamaterial quad band radiating element applicable for Bluetooth, WiMAX, WLAN, and fixed‐satellite service. The radiating element designed is composed of an inner angle‐rotated circular Split Ring Resonator (SRR) placed within the outer square‐shaped SRR interlinked by a strip to design the multiband operational characteristics and is fed by a coplanar waveguide. Suggested radiating element is imprinted over the FR4 substrate material with the electrical dimension of 28 × 31.26 × 0.8 mm3. The initial outer‐closed square ring offers dual‐band operation by resonating at 2.8 and 8.5 GHz frequencies, and the incorporation of a circular SRR offers quad‐band operation. The unique negative permeability feature of the proposed Square and Circular Split Ring Resonator (SCSRR) structure is extracted, and its band characteristics are analyzed. Results obtained from the simulated radiating element are validated with the fabricated antenna. The measured E plane pattern resembles a numeric eight shape, and the H plane pattern is omnidirectional. Suggested SCSRR antenna offers a gain of above 3.2 dBi in all the operating bands.

A Study of Dielectric Effects on Resonance Frequency of a Spit Ring Shaped Inclusion

Resonator designs are central to the development of subwavelength unit structures of metasurfaces to create exotic and unique electromagnetic properties by modifying the host structure to tune impinging electromagnetic waves. The act of intentional control of propagating electromagnetic fields are actively being explored in wireless radio environment control for sixth generation (6G) and beyond. In this paper, we study the effect of dielectric properties on electric field distribution and resonance frequency of a circular split ring resonator (SRR). The subwavelength resonator structure is modelled and simulated using High Frequency Structure Simulation (HFSS) software. Rogers RO3003 and RO3210 were used at different thickness to study the field distribution and its effect on resonance frequency of the SSR. The results show a decrease in resonance frequency of 38.41% from RO3002 (lower relative permeability of 3) to RO3210 (higher relative permeability of 10.2). With change in Rogers RO3210 thickness from 1mm to 1.525mm, the resonance frequency has changed from 5.5GHz to 5.2313 GHz. This indicates that the material composition of the substrate and the physical dimension of the SRR unit cell affects the resonance frequency of the structure.&nbsp;&nbsp;&nbsp;&nbsp

Angle-independent wideband metamaterial microwave absorber for C and X band application

Abstract In this article, an angle-independent wideband metamaterial microwave absorber (MMA) for C (4–8 GHz) and X (8–12 GHz) band frequency is presented. The unit cell of the proposed MMA consists of outer and inner structure associated with lumped resistors. The outer structure consists of rectangular split-ring resonator, whereas the inner structure consists of circular split-ring resonator. The structure is made up of three layers, in which top and bottom layers are made up of copper acting as a conducting material. The middle layer is made up of FR-4 acting as a dielectric substrate. The resonating structure at the top is designed in such a way that wideband absorption is achieved in the range from 6.11 to 13.52 GHz. The wideband absorption within the range approaches almost unity having a bandwidth of 7.41 GHz. Three different peaks are considered in the range of interest having maximum absorption of 0.94, 0.94, and 0.99 at frequencies of 6.76, 11.15, and 13.07 GHz, respectively. The structure is analyzed with respect to the effective parameters, i.e., effective permittivity ( ${\varepsilon _{{\textrm{eff}}}}$ ) and effective permeability ( ${\mu _{{\textrm{eff}}}}$ ), to prove that the structure acts as a metamaterial. Electric field and current distribution are plotted at three different peaks to prove the mechanism of wideband absorption. Normal and oblique incidence are plotted to determine that the structure is behaving as an angle independent. The simulated structure is fabricated on FR-4 substrate and measured inside an anechoic chamber. Finally, to prove the novelty of the work, the proposed structure is compared with the already reported MMA. The proposed MMA finds practical applications in radar cross section reduction, terrestrial communication, keyless entry system, space communication, radar, and baby monitor.

Design of Sub-6 GHz Antenna using Negative Permittivity Metamaterial for 5G Applications

Abstract: The objective of the presented article is to design a compact metamaterial-based dual-band antenna that meets the frequency requirement of 5G. The antenna consists of a Circular Split Ring Resonator structure with a defective ground plane and slots to enhance the bandwidth and gain parameters. Metamaterial-based Microstrip patch antenna produces unique electromagnetic properties that allow us to control over the antenna parameters with a compact size. FR-4 epoxy is used as a substrate its dielectric constant is 4.4 and its loss tangent is 0.02. Dimensions of the antenna are 20 x 12 x 1.6mm3 with a very compact size and cost-effective. The proposed metamaterial-based antenna resonates at dual bands at 3.24GHz and 5.46 GHz respectively. The peak gains at resonant frequencies 3.45GHz and 5.46 GHz are 0.9 dB and 2dB respectively. The proposed antenna shows S-parameters at S11, which is -12.13dB at frequency of 3.45 GHz and -15.165 at a frequency of 5.46 GHz. The proposed antenna can effectively work for WLAN and WiMAX applications. The antenna covers the frequency spectrum from 2 GHz to 8 GHz with a centre frequency of 5 GHz. The proposed antenna is cost-effective