High Frequency Structure Simulator Research Articles

Designing Symmetric Gradient Honeycomb Structures with Carbon-Coated Iron-Based Composites for High-Efficiency Microwave Absorption

HighlightsMIL-88C (Fe) with varying aspect ratios as a precursor was synthesized by regulating oil bath conditions, followed by one-step thermal decomposition to obtain carbon-coated iron-based composites.High-efficiency microwave absorption properties were achieved with RLmin value of -67.4 dB (2.13 mm) and wide effective absorption bandwidth (EAB) of 5.52 GHz (1.90 mm) under the low filler loading.A symmetric gradient honeycomb structure was constructed utilizing the high-frequency structure simulator, achieving an EAB of 14.6 GHz and a RLmin of -59.0 dB.

A novel slotted antenna design for future Terahertz applications

A slotted patch antenna operating at 118 GHz is proposed to address challenges in the terahertz (THz) frequency band for wireless communication systems. The antenna design, utilizing a Rogers RO3003 substrate, which has a dielectric constant of 3 and tan 0.001, strategically incorporates slots to enhance key performance parameters. Copper is employed for the ground and radiating patch, and a microstrip feeding method powers the antenna. High frequency structure simulator (HFSS) software is used for design and simulation, revealing resonance at 0.118 THz with a reflection coefficient of -42.41 dB and an impedance bandwidth of 4.42 GHz (115.84–120.26 GHz). At the operating frequency, the antenna exhibits a gain of 7.36 dB, maximum directivity of 7.38 dB, the voltage standing wave ratio (VSWR) of 1.01, and 99.75% radiation efficiency, all within a compact size of 1.5×1.3×0.1 mm³. The suggested antenna outperforms recent counterparts, making it suitable for applications like security screening and wireless communication systems (5G). Future efforts will target bandwidth expansion, gain enhancement, and further size reduction to enhance overall performance.

Design and Analysis of Microstrip Sierpinski Fractal Antenna for Wireless application

This paper describes a novel design for a microstrip fractal antenna based on the Sierpinski triangle shape. It is built on a FR4 substrate and operates in the 5.5 GHz frequency range. The proposed antenna is designed and validated using ANSYS Electronic Desktop's High Frequency Structure Simulator (HFSS). The simulated results show good performance in terms of radiation pattern, gain and input impedance. This proposed antenna can be widely used in wireless communication equipment that is progressing towards miniaturization and high frequency. The antenna designed gives a return loss of -29 dB at 5.53GHz. It has a gain of 0.85 dB and directivity of 1.8dB.

Performance analysis of quad-port UWB MIMO antenna system for Sub-6 GHz 5G, WLAN and X band communications

A quad-port Multiple Input Multiple Output Antenna with high isolation is presented in this paper. The MIMO design is intended to receive Ultra-Wide Band response to target various wireless applications. The engineered model has 40 x 40 × 1.6 mm3 electrical dimensions. A single antenna achieves size compactness due to an appropriate inclusion of vertical and horizontal conductive strips. Additionally, a diagonal radiating strip is shaped and pooled with the patch geometry. A similar design is positioned orthogonally with each other to receive diversified performance. The four conducting ports are positioned with an appropriate minimum distance to lower down the possible mutual coupling. A partial ground plane having border geometry has been incorporated to receive the ultra-wide band response. An additional plus-sign shaped conducting strips are provided and united with ground lines for isolation enhancement. The MIMO system exhibits ultra-wide frequency response from 3.20 GHz to 13.40 GHz with adequate isolation below −20 dB and an impedance bandwidth of 10.20 GHz. The proposed structure provides an overall gain of 2 dBi having above 80 % efficiency. The presented radiator exhibits excellent MIMO diversity response achieving minimal mutual coupling effect. The other output parameters such as envelope correlation coefficients<0.05, diversity gain of nearly 10 dB, mean effective gain<0.2 dB, and channel capacity loss<0.1 bits/sec/Hz were obtained. The proposed design has been simulated in High Frequency Structure Simulator (HFSS) software. The developed MIMO antenna has been analyzed through VNA N9912A. An encouraging correlation between the software generated and actual responses was observed. The strong agreement between actual results and software results shows the design potential for wireless communications. The highly isolated MIMO system registers its potential for sub-6 GHz 5G, WLAN, and X Band communications.

Design and Modeling of a Terahertz Transceiver for Intra- and Inter-Chip Communications in Wireless Network-on-Chip Architectures.

This paper addresses the increasing demand for computing power and the challenges associated with adding more core units to a computer processor. It explores the utilization of System-on-Chip (SoC) technology, which integrates Terahertz (THz) wave communication capabilities for intra- and inter-chip communication, using the concept of Wireless Network-on-Chips (WNoCs). Various types of network topologies are discussed, along with the disadvantages of wired networks. We explore the idea of applying wireless connections among cores and across the chip. Additionally, we describe the WNoC architecture, the flip-chip package, and the THz antenna. Electromagnetic fields are analyzed using a full-wave simulation software, Ansys High Frequency Structure Simulator (HFSS). The simulation is conducted with dipole and zigzag antennas communicating within the chip at resonant frequencies of 446 GHz and 462.5 GHz, with transmission coefficients of around -28 dB and -33 to -41 dB, respectively. Transmission coefficient characterization, path loss analysis, a study of electric field distribution, and a basic link budget for transmission are provided. Furthermore, the feasibility of calculated transmission power is validated in cases of high insertion loss, ensuring that the achieved energy expenditure is less than 1 pJ/bit. Finally, employing a similar setup, we study intra-chip communication using the same antennas. Simulation results indicate that the zigzag antenna exhibits a higher electric field magnitude compared with the dipole antenna across the simulated chip structure. We conclude that transmission occurs through reflection from the ground plane of a printed circuit board (PCB), as evidenced by the electric field distribution.

Frequency selective asymmetric coupled-fed (ACS) antenna using additive manufacturing

In this study, the development of diverse antenna designs using additive manufacturing processes, specifically spanning from L-band to K-band is proposed. All designs are implemented on a flexible FR4 substrate to make them suitable for wearable sensors and biomedical applications. The fabrication process involves the utilization of aerosol jet printing with nanoparticle silver ink, followed by curing in a vacuum chamber. Additionally, screen printing with copper paste is employed as another method, with subsequent curing in a laminator. The reflection coefficient (S11) and radiation patterns for the simulated design and fabricated samples were found to align closely. The achieved return loss consistently reaching −10 dB across fairly large operating frequency range underscores the efficacy of the proposed antennas and their associated additive manufacturing mechanisms. The design and simulation were performed using Ansys high frequency structural simulator (HFSS), and the parameters under test for the fabricated antennas were validated using a vector network analyzer (VNA) to assess overall performance.

High-gain TM11 mode equilateral triangular patch antenna with shorting pins and triangular short horn

Abstract Normally, the reported gain of the microstrip patch antenna is within 8 dBi. Using properly located three shorting pins on three bisectors, the present work reports a method to convert the non-radiating TM11 mode of equilateral triangular patch antennas (ETPAs) to a deformed TM11 radiating mode. The boresight gain of ETPA operating in TM11 mode is enhanced from −10.75 to 12.1 dBi at 5.43 GHz. The boresight measured gain is further enhanced to 14.2 dBi at 5.52 GHz by using a triangular surface-mounted short horn (SMSH) of about ${{\lambda }}/5$ height. The aperture efficiency of the ETPA with the shorting pins is 84.2%. The aperture efficiency is further improved to 94.2% using the SMSH. The measured boresight cross-polarization and side-lobe level are −40 and −29 dB, respectively. The nature of the electricfield and surface current distribution is analyzed, using both the characteristic mode analysis method and high-frequency structure simulator, to understand the role of shorting pin and coaxial feed in converting the non-radiating TM11 mode to the radiating mode. A systematic design process also is presented for a fast design of shorting pin-loaded ETPA on the suitable substrate at a specified frequency.

Investigating a Cylindrical Dielectric Resonator Antenna Fabricated with Li3MgNbO5 Microwave Dielectric Ceramic

This work aims to fabricate a single-feed line Cylindrical Dielectric Resonator Antenna (CDRA) using low-temperature sintered Li3MgNbO5 microwave dielectric ceramic as a resonator, excited in HEM11δ mode. The ceramic synthesized using the conventional solid-state route resulted in a single-phase material exhibiting a cubic structure with an Fm-3m space group. The densely packed cylindrical disk of the ceramic was subsequently characterized for its microwave dielectric behaviour in TE01δ mode using the Hakki-Coleman method. The dielectric permittivity (ε r) measures 14.4, with a loss factor (tan δ) nearly equal to 4.01 × 10−4 and a temperature coefficient (τf) of −50.9 ppm °C−1. The antenna design was executed using the high-frequency structure simulator design software, utilizing the dielectric ceramic as the resonator, Cu strip as the feedline, and FR4 as the substrate. The maximum energy was coupled to the antenna when the resonator was placed at 11.75 mm on the substrate. The fabricated CDRA, using appropriate simulated parameters, resonated at 7.67 GHz, offering a return loss (S11) of −32.64 dB and an impedance bandwidth of 10.73%. Furthermore, the CDRA displayed a voltage standing wave ratio of 1.04, ensuring a nearby ideal impedance match and a bandwidth of 810 MHz to support high-speed data transmission.

Design of Microstrip Array Antenna for Vehicle Millimeter Wave Radar

The design and construction of a microstrip array antenna especially intended for vehicle millimeter-wave radar applications in the 77–81 GHz frequency range is presented in this study. This study relies on earlier research on single-patch antennas to provide a full array design that satisfies the demanding performance requirements necessary for sophisticated car radar systems. The study carefully models and analyzes the antenna array using the High-Frequency Structure Simulator (HFSS) to get an azimuth angle of 90° within a 6 dB beamwidth and a pitch angle of 10° ± 1° within a 3 dB beamwidth. Achieving a gain of more than 13 dBi, keeping sidelobe levels below −15 dB, and guaranteeing isolation of more than 35 dB are all priorities in the design process. Precision and interference avoidance are crucial in high-resolution, short-range radar systems, and these factors are essential to the antenna’s operation. The array’s small form factor, along with factors like easy integration and economical production, make it an excellent choice for contemporary automobile radar applications. The research addresses the wider ramifications of this technology in vehicle safety and navigation in addition to diving into the technical issues of antenna design, such as the optimization of element spacing, array layout, and material selection. By exploring the limits of high-frequency antenna performance, this work advances the fields of autonomous cars and wireless communication technologies. The designed antenna array architecture is very adaptable, as shown by its possible applications ranging from point-to-point transmission and satellite communication to vehicle radar systems. The goal of this effort is to improve the capabilities of vehicle radar systems, which will lead to safer and more effective autonomous navigation solutions.

Design of Dipole Antenna at 433 Mhz ISM Band for Underwater to Land Communication

In this research has been designed dipole antenna which is intended for communication underwater to land that worked and implemented into prototype form. Design using the software Ansoft High Frequency Structural Simulator (HFSS) v13 and analyze parameters which are generated in simulation results, namely the Voltage Standing Wave Ratio (VSWR), reflection coefficient (S11), the radiation pattern of two-dimensional and three-dimensional. On its design was made of two dipole antennas that can work in a system as a transmitter and receiver. Both of these Dipole antenna operating at ISM 433 MHz frequency band and produce VSWR = 1.62 at the transmitter antenna and = 1.406 on the receiving antenna. In addition, has been measured radiation patterns by antenna performance. From the results of radiation patterns measurements, obtained two pieces of Main Lobe in its field azimuth.

Optimisation of asymmetries in mm-wave single-element fractal antenna for gain-bandwidth enhancement

ABSTRACT In this study, a low-loss substrate was used to create an Asymmetric Irregular Hexagonal Fractal (AIHF) mm-wave antenna. The antenna consists of an Asymmetric Defected Ground Structure (ADGS) attached to the bottom of a 0.55λ0 ×0.40λ0 ×0.032λ0 mm3 substrate and an Irregular Hexagonal Fractal (IHF) patch on top of the substrate. The proposed fractal technique is unique and based on fractal-slot 3-stage iterations. The IHF patch is created by etching seven fractals arranged symmetrically about the y-axis, one of which has a central 1/3rd (scaling) iteration factor and six hexagonal fractals that are 1/9th of the parent 0th order iteration. On the patch, these fractal slots are evenly spaced out. By etching an Asymmetric Cascaded Double Dumbbell (ACDD) slot on the ground plane, an ADGS is created. With this etching in the patch and ground, a gain of > 5.0 dBi for a −10 dB S11 bandwidth of 4.655 GHz (32.84–37.215 GHz), a recorded peak gain of 13.4 dBi is at 33.55 GHz and an average radiation efficiency of 87.75% is achieved. Using the High-Frequency Structure Simulator (HFSS), the width of ADGS, the position of ACDD on ADGS, and the dimensions of etched fractals are optimised through a pattern search parametric iterative technique. These results are validated using the Vector Network Analyser (VNA), and the Anechoic Chamber and it is revealed that they agree well with the simulated results. The designed AIHF antenna’s RLC electrical equivalent circuit modelling is presented along with evaluated R, L, and C values.

Improved design and performance of the global rectenna system for wireless power transmission applications around 2.45 GHz

This work proposes a new conception of the global microstrip rectenna system operating around 2.45 GHz. This improved rectenna system associates a receiving antenna with a rectifier circuit. This rectenna is printed on an FR4 substrate. The proposed antenna is a 1×4 microstrip antenna patch array with pentagonal patches using the defective ground structure method and operates with circular polarization. To show the effectiveness of this array, the results obtained by the computer simulation technology microwave studio (CST MWS) software prove that this array is good in terms of high gain, high directivity, high efficiency, wideband, small volume, and well-adaptation, and all these results are confirmed by another solver high-frequency structure simulator (HFSS). The improved rectifier is a microstrip rectifier that uses an HSMS2852 Schottky diode by using a series topology. The effectiveness of this rectifier is proved by the simulation results using advanced design system (ADS) software in terms of well-matching input impedance, high efficiency, and important output direct current (DC) voltage value. The proposed rectenna system is more efficient compared with the existing works and is very appropriate for several applications of wireless power transmission to power supply electronic instruments in various fields cleanly on our planet.

Reciprocal and non-reciprocal electromagnetic wave propagation in sub-100 nm epitaxial YIG thin films deposited under different oxygen growth pressure

Directional dependent transport of information in magnetic thin films offers a great opportunity to realize reciprocal and nonreciprocal microwave devices, such as filters, phase shifter, isolators and circulators. Electromagnetic wave (EM) propagation in sub-100 nm thin magnetic film is critical, yet reciprocal and non-reciprocal wave propagation and its accurate measurements remain a challenge. We investigated reciprocal and non-reciprocal wave propagation in 90 nm thick epitaxial thin films of yttrium iron garnet (Y3Fe5O12:YIG) grown by pulse laser deposition (PLD) technique on gadolinium gallium garnet [GGG(100)] substrates. The effect of oxygen growth pressure during deposition of YIG films exhibit directional dependence properties of electromagnetic wave propagation. The reciprocal EM wave propagation was generated by a S-type transmission line to achieve microwave (RF) magnetic fields (hRF) perpendicular to applied dc magnetic fields (HDC), to ensure the ferromagnetic resonance (FMR) condition. The center frequency is tuned up to 20 GHz with an applied magnetic field of 6 kOe. The tuning of the center frequency was achieved as of 85.3 % with HDC of 6 kOe. To achieve non-reciprocal EM-wave propagation one straight microstrip line was used to ensures a parallel configuration (parallel pumping FMR condition) of hRF to HDC. The nonreciprocity observed is due to the presence of gyrotropic properties in the YIG thin films and it enhances when YIG film was placed in asymmetric geometry. Further, oxygen growth pressure (>0.1 mbar) grown YIG films enhances the nonreciprocity by 21.6 %. The experimental results were successfully validated using high-frequency structure simulator (HFSS). Hence, these results indicate that controlled deposition parameters can be a crucial parameter in the design of reciprocal and nonreciprocal microwave signal processing devices.

A Broadband Microstrip Antenna with a Strip-Slot Hybrid Structure

In order to solve the problem of narrow bandwidth of traditional microstrip antenna, a broadband patch antenna with Y-shaped microstrip feeder is proposed in this paper, which has the advantage of wider bandwidth and similar radiation pattern characteristics than the traditional microstrip slot antenna. Firstly, the Y-shaped microstrip line is used as the feed based on the straight microstrip line. Secondly, the strip-slot hybrid structure is used based on the square patch. Then the strip-slot hybrid structure is slotted. Finally, the impedance matching is achieved by optimizing the size of the antenna, which greatly widens the impedance bandwidth of the antenna. The full wave simulation software of high frequency structure simulator (HFSS) is used to simulate the proposed antenna structure. The simulation results show that when the reflection coefficient is less than -10dB, the relative bandwidth of the antenna is 22% (4.48-5.60GHz), and the maximum gain of the antenna is 10.72dB.

Design and optimization of a compact microstrip BPF for wireless communication systems based on open-loop rectangular resonators

In a wireless communication chain, filters play a critical role in ensuring the efficiency, reliability, and overall performance of the system. In fact, filters are essential for selecting specific frequency bands. They can narrow or widen the bandwidth, depending on the requirements of the communication protocol. Appropriate bandwidth management is crucial for optimizing data transmission rates and accommodating multiple channels within the available spectrum. This article describes the design of a compact bandpass filter with two identical rectangular open-loop resonators. The proposed filter frequency response covers the 3.5 GHz global interoperability for microwave access (WiMAX) and fifth generation (5G) applications. The structure of this filter uses the Rogers RO6010 substrate, which has a dielectric constant of 10.2, thickness of 1.27 mm, and tangent loss of 0.0023. The proposed device is intended for wireless communication systems operating at 3.5 GHz. The filter offers a wide bandwidth of 1.21 GHz with a small size of (5.72 × 12.34) mm2, and a low insertion loss of −0.16 dB. The suggested filter offers effective utilization across various applications including fifth-generation (5G), sub-6G, and WiMAX. Simulation and optimization of the proposed design are conducted utilizing the HFSS (High Frequency Structure Simulator) software. To corroborate the results from HFSS, the ADS (Advanced Design System) software is employed. The simulation outcomes obtained from both HFSS and ADS simulators demonstrate close resemblance.

Two split rings resonator-based perfect metamaterial absorbers with the incident and polarization angle independent for sensing applications

The perfect metamaterial absorber (PMA) optimized for high-performance absorbers to find the multiple sensing application. The structural composition of the PMA consists of two split ring resonators with six split gaps configured in an exhibit symmetry of rotation. The fundamental component of the design has three distinct layers: (1) the top and bottom layers, composed of a metallic substance with copper dielectric substrate with a thickness of 0.035 mm that exhibits lossy metal; (2) the middle layer, made of a lossy dielectric material referred to as Rogers RT5870 dielectric substrate with a thickness of 1.575 mm. The findings reveal that the absorber achieves a broad absorption spectrum, with simulated results from the CST Microwave Studio simulator indicating absorption peaks at 5.88, 9.20, and 15.88 GHz. whereas the strong absorbance is 99.91, 99.99, and 99.97 % with a good quality factor (Q) 29.40, 9.20, 13.23, respectively. The structural dimensions (7 × 7 mm2) are designed to deliver remarkable performance. The tri-band PMA exhibits polarization independent at various angles, including 0, 45, 90, 135, and 180° for both transverse magnetic (TM) and transverse electric (TE) modes. It has excellent absorption capabilities across multiple angles of incidence from 0 to 80°, including the whole operational spectrum. A comparative investigation of the circuit indicates the enhanced performance of the PMA, demonstrating its potential for exceptional functionality inside the advanced design system (ADS) software. Furthermore, the structures under consideration, which were simulated using the High-Frequency Structure Simulator (HFSS), demonstrate a strong agreement with the highest level of absorption seen at each resonance peak in the CST simulation outcomes. This paper introduces an alternative protocol, expressed in terms of the TE and TM modes, for use with the restricted symmetric structure to find multiple sensing application. The proposed study highlights the exceptional properties of PMA provides several practical advantages, including its high absorption capacity, in multiple sensing application, insensitivity to incident and polarization angles, satellite technology, raw satellite feeds, and radars owing to these performance features.

A High-Gain Directional 1 × 8 Planar Antenna Array for 2.4GHz RFID Reader Applications

This research paper deals with a directional high gain PCB [Formula: see text] antenna array for 2.4[Formula: see text]ISM band utilizations. To achieve this antenna array, a well-matched equal-split 9[Formula: see text]dB-power splitter is designed and integrated with the suggested antenna array. It exhibits a wide operating range of 506[Formula: see text]MHz (2.022–2.528[Formula: see text]GHz) and splits the feed power to 8 equal-in-phase output quantities. Then eight identical patch elements with good reflection coefficient, high gain and excellent radiation efficiency are connected at the eight-output ports of the 1 × 8-power divider in order to obtain an array antenna consisting of eight radiating elements. A quarter-wave impedance adapter is utilized to obtain a perfect matching of impedance between patches and the power divider. The suggested directional antenna resonates at 2.4[Formula: see text]GHz with good impedance matching via offering reflection coefficient [Formula: see text][Formula: see text]dB and voltage standing wave ratio (VSWR) of 1.16. Moreover, it offers good radiation traits like the enhanced gain of 14.76[Formula: see text]dB, an excellent radiating efficiency equals about 98.86% and a directional radiation pattern. Initially, the proposed planar directional antenna array has been designed and simulated utilizing high-frequency structure simulator (HFSS) EM simulation tool, the results are validated with another simulation tool via computer simulation technology (CST) software. This printed antenna array is a potential candidate to operate at around 2.4[Formula: see text]GHz for RFID reader utilizations due to its outstanding impedance and radiation characteristics.

The Performance Study of Microstrip Patch Antenna Made of Polyurethane - Oil Palm Empty Fruit Bunch Composite

In this paper, the performance of microstrip patch antenna that is made of fully biodegradable materials has been studied. The polymer resins of Polyurethane as a binder agent were produced using polyol extracted from palm oil while the host composites were made from oil palm empty fruit bunch fiber. The performance of Polyurethane – Oil Palm (PolyOP) Empty Fruit Bunch composite as a microwave dielectric substrate was tested by fabricating microstrip patch antenna on it. The performance of fabricated patch antenna was measured using Vector Network Analyzer (VNA) and is compared with simulation results obtained from High Frequency Structure Simulator (HFSS) simulator. The difference of percentage in resonant frequency, return loss, bandwidth and VSWR between simulation and measurement were found to be 0.4%, 75.2%, 67.9%, and 12.7%, respectively.

Theoretical and Experimental Investigation of N-Bit Reconfigurable Retrodirective Metasurface

The PIN diode-based N-bit reconfigurable retrodirective metasurface (N-bit RRDM) is a next-generation retro-reflector that offers the advantages of effective electronical control of the retro-reflection angle, low loss, and thin planar structure. However, since the unit cell of an N-bit RRDM is controlled by a quantized N-bit phase (360°/2&lt;sup&gt;N&lt;/sup&gt;), it encounters operational errors, such as beam gain reduction and spurious beams. This can be a fatal disadvantage in military radar or satellite communication, which requires accurate beam tracking. This paper theoretically analyzes the operation of the N-bit RRDM by utilizing generalized Snell’s law and array factor theory. The analysis results present the design criteria for an N-bit RRDM that eliminates issues related to beam gain reduction and spurious beam errors. Furthermore, to verify the theoretical analysis results, High-Frequency Structure Simulator (HFSS) full-wave simulation and experimentation are conducted using the 1-bit RRDM.

Polarization Agile Reconfigurable Rectangular Patch Antenna for Biomedical Applications

A polarization agile patch antenna resonating at 2.4 GHz ISM band is presented. The antenna is based on a rectangular radiating element along with reconfigurable parasitic patches located at its periphery of the radiating element. Two switching diodes are used to reconfigure the geometry of the radiating element. Upon proper biasing of the switching diodes the antenna attains linear or circular (LHCP/RHCP) polarization states. The entire antenna is modelled using a high-frequency structure simulator and is validated using an Agilent network analyser (N9925A) and antenna test systems for measuring impedance and radiation characteristics. Over the entire operating band, the antenna shows better impedance matching and achieves −10 dB impedance bandwidth of 100 MHz (2.40-2.5 GHz) in linear state and 85 MHz (2.41-2.495 GHz) in the circularly polarization states along with peak gain of 5.61 dBi for LP state and 4.98 dBi for CP state in the operatingrange.