CST Software Research Articles

A Generalized and Efficient Equivalent Circuit Model for Frequency Selective Surfaces

Owing to their excellent intuitiveness and simplicity, equivalent circuit models (ECMs) are widely used to investigate and design frequency selective surfaces (FSSs). However, the generalization and accuracy of ECM has been a contentious issue, especially with regard to the requirement for analyzing diverse and numerous FSSs versus the restrictions applied to it. To address this problem, a generalized and efficient equivalent circuit model (GE-ECM), characterized by the feasibility of dealing with multiple sizes, broadband, and large oblique incidences, is proposed in this study to design FSSs and analyze their electromagnetic performance. In contrast to related works, gap and width factors are accounted for in the proposed GE-ECM to recalibrate the reactance and susceptance of the physical model, respectively. Additionally, normalized sizes of structure periods are introduced to further extend its generalization. Good agreement is achieved between the frequency responses of the GE-ECM and the electromagnetic software CST. Furthermore, excellent adaptation to multiple sizes and broadband is achieved from 0 GHz to 20 GHz, with the average relative error of the resonant frequency being only 1.19% for all sizes. Fabrication and measurements were conducted to verify the practicability of the proposed GE-ECM, with all results confirming its accuracy and universality in interpreting electromagnetic performance, thus establishing a reliable theoretical guideline for designing more complex FSSs.

Electromagnetic coupling evaluation of small metal enclosures with apertures using analytical, numerical and measurement analysis

We have presented an analytical analysis of the shielding effectiveness of small metal enclosures with apertures by the Roinson model based on the theory of transmission line circuits, as well as a numerical analysis by the finite-difference time-domain method (FDTD) and finite integgration technique (FIT) under the CST Software software, the results returned by these methods were compared with those provided by the measurement, the comparative study reveals a good agreement between the simulation and the measurement. The study carried out in this article has resulted in very significant results allowing to solve electromagnetic compatibilty (EMC) type problems related to the reduction of the electromagnetic field in an enclosure with apertrures.

RF NEMS switches based on graphene for low pull-in voltage and excellent RF performance

This study introduces a novel graphene RF NEMS capacitive switch and conducts an extensive analysis of its RF performance using CST and COMSOL Multiphysics software. The switch’s characteristic impedance matching is accomplished through a coplanar waveguide (CPW) structure, incorporating a dielectric layer topped with conductive graphene beam electrodes. Simulation results reveal that the monolayer graphene RF NEMS switch maintains an insertion loss of 0.003 ~ 0.015 dB and an isolation greater than 40 dB across an ultra-wideband (UWB) frequency range of DC ~ 140 GHz. Moreover, the switch demonstrates a switching time of 4.03 ps at a pull-in voltage of 1 V. The performance of multilayer graphene RF NEMS switches was also evaluated. The study further investigates the operational mechanism of the graphene RF NEMS switch and performs finite element analysis on the proposed design. The graphene RF NEMS switch discussed herein offers significant advantages, including minimal size, lightweight, cost-effectiveness, low pull-in voltage, rapid response time, excellent RF performance, and reduced space consumption in circuitry. Its potential applications span a range from L to F bands, encompassing data storage, communication systems, sensors, remote sensing and military uses.

Impedance Matching Using Support Rod Rings in C-Band Helix TWT

A helical (Slow Wave Structure SWS) traveling wave tube (TWT) operating in the C bandwidth was designed using CST software. Based on modelling, TWT components were produced. Conductor support rod rings were used to matching the impedance line and provide ease of assembly. According to the modelling, the signal gain was determined as 30 dB. In addition, Time Domain Reflectometer (TDR) analyses were performed to observe the effect of mounting rings on impedance improvements with the help of software. As a result, it has been determined that the support rod rings, which have not been used before in C band helix TWT systems, positively affect the ease of assembly and impedance improvement.

A novel circularly polarized antenna array methodology for early identification of kidney tumors

Kidney cancer is a significant health concern worldwide, with early detection crucial for successful treatment outcomes. Recently, there has been an increasing focus on investigating affordable and non-intrusive methods for detecting cancer at its early stages. This proposed approach delves into the utilization of antenna arrays to identify kidney cancer. Specifically, antenna array with circular polarization has been crafted to identify tumors in the human kidney. This array design has been implemented using CST software, operating at 2.4 GHz. The antenna array having a dimension of 150 mm x 150 mm. The array consists of four-square patches each having a length of 30 mm and the spacing between the patches is preferred to be 20 mm for ensuring the mutual coupling. FR4 substrate is used with the relative permittivity 4.3 and 1.6 mm thickness. The axial ratio of the circularly polarized antenna is 0.9 dB at 2.4 GHz. The reflection coefficient S 11 = –30dB. The renal phantom in humans has been built with the kidney, adrenal gland, ureter, skin, fat, and muscle components to allow for precise simulation. Following that, four stages of cancer tumors were built employing all of the necessary qualities. For every stage of the cancer tumor, the reflection coefficient growth and resonance frequency shift are calculated. For the initial stages, the resonance frequency shift is very low. Consequently, the primary determinant of detection is the rise in S 11 . For 3rd and 4th stages of the tumor, there is a significant change in resonance frequency and increase S 11 , which facilitates identification. The calculated specific absorption rate (SAR) is a smaller amount than the safety thresholds, indicating that using this method is safe. Overall, this research points to a novel, easy-to-use method for kidney cancer screening. This method has the following benefits: it is non-invasive, safe, quick, affordable, and comfortable, and it emits no ionizing radiation during the measurement process. Furthermore, a range of output parameters such as gain, directivity, and polar radiation have been accurately computed.

Mobile-integrated SRR-based four-port MIMO antenna for broadband mm-wave 5G applications

ABSTRACT A low-profile, single-layered, compact-size, highly-isolated four-port MIMO antenna integrated within a 5 G smartphone has been proposed for a futuristic mm-wave broadband communication system. The proposed MIMO antenna configuration has been derived from a conventional inset-fed rectangular microstrip patch by introducing two parallel I-shaped slots on the patch surface for operating over a wide bandwidth of 4.91 GHz, that is, from 26.78 to 31.69 GHz. The antenna geometry has an overall dimension of 20.9 mm x 20.9 mm x 0.787 mm. The proposed configuration attained a maximum gain of 8.11 dBi and radiation efficiency of 90% at 28 GHz resonating frequency. The integration of the square-shaped SRR structure among closely packed antenna elements has significantly enhanced the overall isolation by 13 dB without compromising the antenna’s physical dimensions. The realisation of the S-parameters has also been carried out from the equivalent circuit model to agree with the results obtained from the electromagnetic simulation through CST software. The measured radiation patterns assured the minimal variation with simulated characteristics along the E and H planes. A comprehensive safety investigation of the proposed MIMO antenna has been carried out to assess power densities (<10 W/ m 2 ) across different usage modes, including data, reading, and talking in a mobile application perspective. Several diversity parameters, including ECC (<0.0001), DG (>9.999 dB), CCL (<0.12 bits/sec/Hz), MEG, and TARC, have also been evaluated as performance metrics. Furthermore, the linear transmission property of the proposed MIMO antenna has been validated through the variation of group delay (<0.5 ns) over operating frequency bands in the far-field region.

Design and Analysis of Wireless Power Transmission (2X1) MIMO Antenna at 5G - Frequencies for Applications of Rectenna Circuits in Biomedical

This research presents the design and analysis of a 5G harvesting energy Circuit (MIMO-rectenna) to receive wireless power at Sub-6 frequencies (5.6 GHz) as a power source for some medical devices carried by a patient and moved from one place to another, whether they are diagnostic or therapeutic devices. This concept aims (MIMO-rectenna) to increase the likelihood of obtaining electricity from the ambient field by harvesting energy at 5G- frequencies. The tiny MIMO (2x1) antenna measuring 30 by 40 mm2 is the antenna portion of this rectenna. It has been built and tested to operate at Sub-6 frequency, or 5.6 GHz, for wireless power transmission applications related to 5G technology. The MIMO antenna has parameters of E = 4.4, h = 1.6 mm, and tand = 0.025 when printed on an FR4 substrate. A significant section of the antenna's rear was removed to carry out the broadband process, and the material's front side was composed of a series of circular slits. In this antenna, the parasitic approach was employed to decrease the mutual coupling between two ports by creating an inverted T with precise dimensions. The CST software 2024 was used to assist with the design and simulation results of this MIMO antenna. It was discovered through the simulation that the mutual coupling for these ports, 𝑆12and 𝑆21, is equal to -51.476 dB, and that the S-parameters, 𝑆11, 𝑆22, equal -22 dB. That is, there is very little signal loss while switching from the first port to the second and vice versa. This antenna's rectifier comprised an AC-to-DC conversion circuit, a DC filter, and an impedance-matching network. With the use of ADS software 2024, this rectenna's design and simulation results were completed. The greatest conversion efficiency of this rectenna at the frequency of 5.6 GHz is determined to be between 65 % and 65.01% for load resistance between 12 KΩ and 15 KΩ at an input power of 14 dBm.

Design of a multi-carrier X-ray source for communication with energy modulation information.

X-ray communication is a kind of space communication technology which uses X-ray as information carrier. In order to improve the information transmission capacity, communication rate and anti-interference ability of X-ray communication, we proposes to design a novel multi-target X-ray source. The source is composed of a fast switching module of light channels based on FPGA technology and four photoelectric X-ray tubes with different target materials: Cr, Fe, Ni, and Cu. Using Geant4 software, we determined the optimal target thickness for each material, which enabled us to fully leverage the characteristic X-rays for multi-channel signal modulation transmission. Moreover, using CST software for particle trajectory simulation and optimization of the electron beam revealed that at a tube voltage of 20 kV, the focus area measures approximately 1.2 mm×1.2 mm. The simulations show that four kinds of spectra with high distinctiveness can be generated from the Cr, Fe, Ni, and Cu targets. Within a single modulation period, these spectra can be combined in various ways to create 16 different X-ray spectra signals, thereby increasing the number of communication elements and enhancing the information transmission rate.

Circular-ring tied arc loaded excellent metamaterial absorber for EMI shielding of Wi-Fi signal and impurity sensing of cooking oil

This paper demonstrates a unique symmetric structure excellent metamaterial absorber (MMA) loaded with circular-ring tied arcs. The FR4 substrate-based MMA can accomplish 98.88 % and 99.81 % absorption maximums at the Wi-Fi and 5G frequencies of 2.4 GHz and 5.0 GHz respectively. The unit cell dimension of 0.16λ0×0.16λ0×0.0128λ0 is considered where the wavelength, λ0 is calculated at 2.4 GHz. The performance of the absorber is analyzed through the electric field, magnetic field, surface current, and effective parameters. The dimensions are optimized through the parametric analysis of the developed model in CST software. The model exhibits stability up to 60° for Transverse electric and magnetic polarizations. During electromagnetic interference (EMI) shielding demonstration, it can achieve a high shielding effectiveness (SE) of 54.34 dB at 2.4 GHz and 77.96 dB at 5.0 GHz. For sensing operation, it can attain a quality factor (Q-factor) of 25.61, a sensitivity of 3.30 %, and a figure of merit (FoM) of 84.51. The prototype measurements of the MMA for EMI shielding and impurity sensing of oil samples have a strong correlation with the simulation performance. Because of the high SE, Q-factor, sensitivity, and FoM, the developed MMA can be a competitive candidate in EMI shielding and oil impurity sensing applications.

Coal-gangue recognition for top coal caving face based on electromagnetic detection

Identifying the coal-gangue mixing ratio during top coal caving is essential for automating the coal caving process efficiently. In this article, a block impression reconstruction method is proposed to create 3D models of coal-gangue mixtures with varying gangue ratios and morphological distributions, based on real coal-gangue blocks that reflect actual coal-falling conditions. These 3D models are then input into CST software for electromagnetic forward simulation. The relationship between electromagnetic signal propagation characteristics and gangue ratio is analyzed, resulting in the creation of a coal-gangue mixture electromagnetic signal dataset. An Optuna-XGBoost-based model is then designed to identify the coal-gangue mixing ratio and the recognition performance is firstly verified by using the electromagnetic forward simulation data. Finally, to verify the method’s practicality, a microwave detection test bench for top coal caving is set up and some comparative experiments are conducted. The experimental results indicate that the electromagnetic signals of coal and rock with different gangue contents exhibit significant differences, and the proposed coal-gangue identification model has significant advantages in accuracy and overall performance compared to other competing models.

Design and electromagnetic shielding of Bi0.5Na0.5TiO3 ceramics as meta-surface absorber for high-frequency microwave application

EMI shielding reduces ambient electromagnetic (EM) radiation by reflecting and absorbing EM waves. Rapid technological growth has increased electronic gadgets and EM radiations, threatening the environment. Microwave materials with high absorption power and cheap cost are crucial for eliminating electromagnetic difficulties in stealth technologies. This study used a conventional solid-state reaction technique to prepare Bi0.5Na0.5TiO3 (BNT) solid solutions and examined their structural, ferroelectric, dielectric, and shielding characteristics. This research describes an EMI shielding material that efficiently absorbs EM wave-induced radiation. Characterizations have been done to evaluate material behavior to support EMI shielding and confirm its absorbing nature. Field emission scanning electron microscopy (FESEM), Raman spectroscopy, and X-ray diffraction (XRD) were employed to examine the surface morphology, local lattice deformation with ionic configuration, and crystal structure. BNT exhibited a rhombohedral structure with R3c symmetry space group with crystallize size 81.5 nm and showed eight Raman active modes with an average grain size of 1.67 μm. The high dielectric constant, reduced dielectric tangent loss, and enhanced polarization value make BNT ceramic a good choice for electrical devices and microwave applications. BNT ceramics showed EMI shielding owing to absorption (SET ∼ −23.65 dB, SEA ∼ −18.91 dB) at 9.2 GHz in the X-band (8.2–12.4 GHz). Meta-surface-based BNT absorbers were designed and simulated in the CST software. The peak depicted the absorption at 9.2 GHz with absorptivity of 91.56 %, 85.03 %, 84.36 %, and 64.6 % for designs 1, 2, 3, and 4, respectively. BNT ceramics have exceptional dielectric absorption properties, and dielectric and magnetic losses, which make them suitable for EMI shielding and absorption applications in the microwave region.

Terahertz wide-band wide-angle absorber and polarization converter based on VO2 metamaterial

In this study, a Terahertz wide-band wide-angle absorber and polarization converter based on VO2 metamaterial is proposed. The device is simulated by using full-wave electromagnetic computing software CST. The device functions as a wide-band absorber while VO2 is in the metallic mode. In the 1.82 THz to 4.27 THz band, the absorption efficiency exceeds 90% and the relative bandwidth reaches 81.4%. The absorption mechanism is analyzed bying equivalent circuit theory. Additionally, the absorber can work at large polarization angle and incident angle. While VO2 is in the insulated mode, the design can convert the incident y-polarized terahertz wave into the x-polarized state and realize the transformation of linear polarization. Polarization conversion efficiency (PCR) exceeds 90% in the band of 1.57 THz to 3.82 THz, with a relative bandwidth of 83.5%. The device also supports large incidence angle tolerances. These results show that the disigned metamaterial device has potential applications in absorption, polarization conversion and imaging.

Wideband LP to CP Converter Using a Reflectarray Based on Modulated Admittance Surfaces Capable of Wide‐Range Beam‐Scanning for Ku/K Band Applications

AbstractThis study provides the design and demonstration of a Ku/K band horn‐fed linear polarization (LP) to circular polarization (CP) converter using a reflectarray antenna based on the holographic technique and the generalized law of total reflection without any iterative algorithms. The proposed hologram performs wide‐range frequency beam scanning with minimum gain losses and cross‐polarization levels. It comprises 2,500 diagonal slotted octagonal subwavelength metasurfaces with a periodicity of 0.266λ0 = 4 mm at 20 GHz as the center frequency. Two equations are defined to compute Y11 of the proposed unit cell regarding its dimensions for TE(0,0) and TM(0,0) Floquet modes. They significantly simplify the coding procedure and reduce the computational time for synthesizing the hologram. The antenna is simulated using the CST software from 14 to 25 GHz. As a confirmation, a prototype is manufactured and measured at 16, 18, 20, 22, and 24 GHz to verify its performance. The simulated and measured results are well‐matched. The presented hologram achieves 40% 1.8‐dB axial ratio (AR) bandwidth (16–25 GHz), 40% 3.3‐dB gain bandwidth (16–24 GHz), and above 30% 2‐dB gain bandwidth (16–22 GHz). Moreover, the antenna can perform beam scanning from 42° to 24° by changing the frequency from 16 to 24 GHz with peak gain values greater than 20.33 dBi. The LHCP pencil beams are at least 24° off‐broadside, so the proposed hologram avoids the feed blockage. These achievements make the hologram one of the best candidates for satellite communications, radar applications, short‐range communication, and point‐to‐point communication.

Helmholtz–Galerkin Technique in Dipole Field Scattering from Buried Zero-Thickness Perfectly Electrically Conducting Disk

Non-invasive concealed object detection, identification, and discrimination have been of interest to the research community for decades due to the needs to preserve infrastructures and artifacts, guarantee safe conditions for the detection and location of landmines, etc. A modern approach is based on the use of an unmanned aerial vehicle equipped with ground-penetrating radar, which has the advantage of not requiring direct contact with the ground. Moreover, high-resolution underground images are obtained by coherently combining measurements by using a synthetic aperture radar algorithm. Due to the complexity of the real scenario, numerical analyses have always been welcomed to provide almost real-time information to make the best use of the potential of such kinds of techniques. This paper proposes an analysis of the scattering from a zero-thickness perfectly electrically conducting disk buried in a lossy half-space surrounded by air and illuminated by a field generated by a Hertzian dipole located in the air. It is carried out by means of a generalized form of the analytically regularizing Helmholtz–Galerkin technique, introduced and successfully applied by the authors to analyze the plane-wave scattering from a disk and a holed plane in a homogeneous medium. As clearly shown in the numerical results, the proposed method is very effective and drastically outperforms the commercial software CST Microwave Studio 2023.

Study on microwave absorption performance of the skin‐core dual‐domain structure constructed with thin‐ply laminate and honeycomb

AbstractThis study introduces an innovative approach to enhance the absorption capabilities of skin‐core dual‐domain structure radar‐absorbing materials (SDSRAM) composed of thin‐ply laminates and honeycomb. The upper skin laminates consist of transmissive skin and impedance matching layer. The impedance matching layer was hot‐pressed using functionalized absorbed thin‐ply glass fibers prepregs, flaked carbonyl iron powder (FCIP) and multi‐walled carbon nanotubes (MWCNTs) as the absorber. The lower skin was manufactured using carbon fiber‐plated nickel. The core is prepared by honeycomb modified (HCM). The permittivity and permeability of the skin laminates and the HCM were measured by wave‐guide method. The impact of FCIP/MWCNT on the electromagnetic (EM) parameters of the thin‐ply laminates and the influence of MWCNTs on the permittivity of the honeycomb were investigated. Microwave absorption properties of SDSRAM were assessed through the measurement of reflection loss (RL) using the arch method and simulated using the microwave simulation software CST studio suite 2020. Experimental verification was conducted to confirm the absorbing performance. The results show that the effective absorption bandwidth (RL &lt; 10 dB) of SDSRAM covers the frequency range of 2.2–18 GHz, with a maximum absorption intensity of −42.5 dB. The introduction of the thin‐ply laminates caused a shift in the peak of the reflectance curve toward lower frequencies.Highlights Functionalized absorbed glass fibers were prepared using fiber spreading functional sizing integrated process. A new skin‐core dual‐domain synergistic modulation absorbed structure was developed with thin‐ply laminates and modified honeycomb. Its broadband absorption mechanism was discussed. Desired broadband absorption performance was acquired with thin thickness.

Design of a UWB patch antenna and performance evaluation in detecting brain tumors

In this study, a patch antenna is designed for easy fabrication and effective operation across a wide frequency range, making it particularly valuable for detecting brain tumors within a human head phantom using the monostatic technique. The study presents the proposed antenna's modeling in four stages, analyzing all essential parameters where a substrate material consisting of FR 4 is used. The antenna has a patch area of 0.27 λ × 0.21 λ and operates at 7.5 (free space), 7.48, and 7.47 GHz with a wide bandwidth of 3.188 GHz (free space), whereas in measurement, it operates in free space at 6.79 GHz with a bandwidth of 3.24 GHz, which is also categorized as an ultra-wide band. A comparative analysis is carried out between the proposed patch antenna and previous studies utilizing FR4 and similar substrate materials to enhance understanding. In this research, the analysis includes a human head phantom model, assessing key performance criteria such as SAR, return loss, and VSWR. The time-dependent analysis provides in this study insights into the dynamic behavior of the system in detecting brain tumor. The proposed antenna has been evaluated and yielded a maximum specific absorption rate (SAR) of 0.420985 W/kg for 1 gram of tissue in the head phantom. The performance of the patch antenna is evaluated using CST software, while the fabricated PCB antenna is tested in real-world conditions to ensure dependable operation in practical applications. The main challenge addressed in this work is achieving accurate brain tumor detection within a human head phantom model in a CST environment and using a UWB patch antenna fabricated via PCB technology.

Multiband multiple‐input multiple‐output antenna design with high‐resolution circularly polarized wireless communication

SummaryA design problem of multiband multi‐input, multi‐output (MIMO) antenna arrays for maximal side lobe level lessening with constraint of a fixed beam width is dealt with. Multiband MIMO antenna is the most promising solution in a communication system, due to its maximal speed, higher data rate, and short‐range communication. Conversely, MIMO faces several complications including designing a proper antenna for a specific bandwidth and lesser antenna efficacy. In this manuscript, a high‐resolution CP multiband MIMO (HS‐CPMB‐MIMO) antenna design for wireless communication is proposed. MIMO antenna plays a vital part in the present wireless technology at MSA. A multiband microstrip line‐fed two‐port hybrid CPMIMO antenna is intended and fabricated. The proposed microstrip feed antenna contains a tapering structure, and the inverted L‐shaped slots in the radiating element are opened on both sides to present notches in sub‐6‐GHz frequencies. The inverted L‐shaped slots is positioned in the middle of asymmetric Z‐shaped radiating elements for enhancing the isolation among the two ports. The invention of a multiband MIMO antenna with four CP bands has an efficient ECC value because of a large L‐shaped slot in the ground as well as a protruding Z‐shape ground stub embedded with circular rings to have highly isolated cells. Finally, the proposed HS‐CPMB‐MIMO antenna design is implemented by utilizing simulation software CST Microwave Studio, and it is evaluated with the performance metrics. The simulation outcomes of the proposed HS‐CPMB‐MIMO antenna provide 36.34%, 57.36%, and 25.33% higher BW, 24.13%, 15.96%, and 21.22% higher gain compared with existing methods.

A Tunable Plasmonic Perfect Absorber based on Graphene and Two Metal-insulator Substructures

Background: In recent decades, numerous researchers have been keenly interested in plasmonic absorbers due to their efficiency in a variety of applications such as solar cells. This is because the surface plasmons formed at the interface between metal and insulators interact strongly with light, thereby augmenting electromagnetic (EM) waves. In most cases, plasmonic absorbers featuring metal-insulated-metal structure (MIM) are favored for their robust absorption rates, straightforward fabrication process, minuscule size, and portability. Methods: This paper proposes a tunable plasmonic perfect absorber (PPA) based on graphene and two metal-insulator substructure within the 28-60 μm wavelength range. This device is simulated by 3D finite element analysis using CST software. Also, in our proposed structure, instead of using a single micro-blade, two micro-blades are arranged opposite of each other in the absorber structure through which the electric field is locally strengthened and a sharper resonance peak with greater amplitude is obtained. Results: Simulation results demonstrate that a resonance peak is observable in the absorption spectrum of the structure and that this peak can be shifted between 30μm and 40μm by applying a gate bias voltage to the graphene nanolayer without modification of the structure's dimensions. Conclusion: The features of this absorber make it suitable for sensor applications, which will be further explored in future research. We also investigated the influence of dimensions on absorption to take into account the allowable tolerances and sensitivities associated with its fabrication. Furthermore, we proposed a structure that can enhance absorber performance in the future.

RBFNN-based UWB 4×4 MIMO Antenna Design with Compact Size, High Isolation, and Improved Diversity Performance for Millimeter-Wave 5G Applications

Abstract The millimeter-wave spectrum has emerged as a compelling solution to address the pressing need for high-datarate&amp;#xD;capabilities in the development of 5G technology systems. Spanning between 20 GHz and 40 GHz, this spectrum&amp;#xD;encompasses several prominent frequency bands crucial for advancing 5G applications. In light of this, our study&amp;#xD;presents a thorough investigation into the design and performance of a compact cross-shaped slot broadband antenna,&amp;#xD;complemented by a 4×4 Multiple-InputMultiple-Output (MIMO) configuration tailored for 5G operations at&amp;#xD;28 GHz. The primary objective of this study is to develop an antenna system capable of achieving an extended bandwidth&amp;#xD;ranging from 20 GHz to 40 GHz, effectively covering the crucial frequency bands essential for 5G millimeterwave(&amp;#xD;mmWave) operations. To accomplish this, the optimization of antenna performance is meticulously carried out&amp;#xD;using the Radial Basis FunctionNeuralNetworks (RBFNN) model. The RBFNNmodel serves as a robust tool for establishing&amp;#xD;the intricate relationship between antenna dimensions, resonant frequency, and bandwidth. Subsequently,&amp;#xD;the developed RBFNN model is employed to predict optimal antenna dimensions, ensuring resonance at 28 GHz and&amp;#xD;meeting specified bandwidth targets. The single antenna is designed with a rectangular patch and a cross-shaped&amp;#xD;slot and is constructed on the low loss Rogers RT Duroid 5880 substrate. This design reaches an outstanding bandwidth&amp;#xD;of 19.5 GHz, and exhibits excellent radiation characteristics, with a high radiation efficiency of up to 99% and a&amp;#xD;corresponding gain of 5.75 dB. The antenna’s design and performance are rigorously designed using HFSS software,&amp;#xD;which is then compared to the results acquired using CST software. In addition, the proposed MIMO configuration&amp;#xD;offers excellent performance in terms of key features such as small size (16 × 16.2 mm2), very wide bandwidth of 20&amp;#xD;GHz, good gain of 6.75 high isolation exceeding 35 dB, and significant improvements in diversity performance measures&amp;#xD;such as Envelope Correlation Coefficient (ECC), Diversity Gain (DG), Channel Capacity Loss (CCL), Total Active&amp;#xD;Reflection Coefficient (TARC), and Mean Effective Gain (MEG). The potential of the proposed MIMO configuration&amp;#xD;for high-speed applications is particularly remarkable. Practical verification of the MIMO configuration is carefully&amp;#xD;carried out by fabrication andmeasurement. Experimental results strongly confirmthe effectiveness of the proposed&amp;#xD;antenna design, establishing it as a competitive challenger for 5G technology.

A Dual-Band Wearable Antenna for X and Ku Frequency Bands for Satellite Communication Applications.

In the present research, a novel 3 cut-pentagon dual-band antenna design has been introduced, and its attributes and performance are enhanced through the use of a specialized substrate called "Jeans" with a permittivity of 1.7. The conducting element employed is copper tape. The design and study of a dual-band wearable antenna optimized for X and Ku frequency bands, specifically tailored for satellite communications applications. The antenna is engineered to offer reliable and efficient performance within the X-band (6.31 GHz) and Ku-band (8.07 GHz) and extended resonant frequency 12.118GHz facilitating seamless connectivity in satellite communication networks. The board size is 43x25.5 mm^2. The Bandwidth for the first band of the suggested antenna is 37.58% for the frequency range between 5.87 GHz. To 8.587 GHz and the bandwidth for the second band is 12.85% for the frequency range 11.447 GHz to 13.02 GHz. The dual-band wearable antenna, which operates in two frequency bands, is created and simulated using CST software