Compact Antenna Research Articles

Design and Implementation of a Partially-Grounded Dual-Band Compact Patch Antenna with Enhanced Selectivity for Multiservice Wireless Communication Applications

Design and Implementation of a Partially-Grounded Dual-Band Compact Patch Antenna with Enhanced Selectivity for Multiservice Wireless Communication Applications

Directivity Improved Antenna with a Planar Dielectric Lens for Reducing the Physical Size of the On-Vehicle Communication System

As the physical size of a communication system for satellites or unmanned aerial vehicles demands to be reduced, a compact antenna with high directivity is proposed as a core element essential to the wireless device. Instead of using a horn or an array antenna, a unit planar antenna is combined with a surface-modulated lens to convert a low antenna gain to a high antenna gain. The lens is not a metal-patterned PCB but is dielectric, which is neither curved nor very wide. This palm-sized lens comprises pixels with different heights from the backside of PolyPhenylene Sulfide (PPS) as the dielectric base. The antenna gain from the unit antenna of 4.5 cm × 4.5 cm is enhanced by 10 dB with the help of a compact dielectric lens of 7.5 cm × 7.5 cm at 24.5 GHz as the frequency of interest. The antenna design is verified by far-field measurement as well as near-field observation, including sensing a metal object behind a blocking wall by using an RF test bench. Moreover, antenna performance is understood by making a comparison with conventional designs of antennas in terms of directivity and physical sizes.

Compact and Simple Antenna Inspection Testing Range for 5G Smartphones

Abstract Over-the-air (OTA) antenna performance evaluation in the millimeter-wave (mmWave) band often relies on Compact Antenna Test Range (CATR) systems, which require large reflectors and a substantial measurement range volume. Such setups are impractical for rapid testing in space-constrained environments such as antenna fault diagnosis in smartphone manufacturing facilities. This paper presents a novel design methodology for highly compact antenna inspection testing range utilizing offset parabolic reflectors specifically designed for 5G smartphones. The proposed design system employs three small offset parabolic reflectors configured to account for beam tilting caused by smartphone back covers, eliminating the need to physically reposition the smartphone during testing. By directing electromagnetic fields toward a fixed receiver antenna from multiple angles corresponding to different antenna module positions, the system streamlines the test procedure, significantly reducing measurement time and measurement range volume. The proposed antenna inspection testing range provides a cost-effective and efficient solution for 5G antenna fault diagnosis in manufacturing facilities, ensuring rapid and reliable inspection while minimizing space requirements on the production line.

Design and Analysis of Sierpinski Fractal Antennas for Millimeter‐Wave 5G and Ground‐Based Radio Navigation Applications

ABSTRACTThe paper describes compact fractal antennae combined with ground defected structures (DGS) and substrate integrated waveguide (SIW) techniques for enhancing resonate and multiband behavior concerning bandwidth, gain, and radiation in the desired mm‐wave region. Based on the proposed antennae, multiple good notches over wide bands depict a good radiation pattern. The antennae's ultra wide bandwidths (UWB) are 16, 16, and 11.4 GHz concerning resonant frequencies 26.34, 30.35, 34.5, 36.65 GHz; 25.8, 32.2, 35.3 GHz; 30.22, 37.68 GHz, of concerning antennae ant 1 (FA1), 4 (FA2), and 6 (FA3), respectively. The proposed antenna (FA3) with the SIW technique has a peak gain of 5.9 dBi and a peak front‐to‐back ratio of 20 dB, respectively. The proposed antennas are targeted to cover the practical contribution aspect, including advanced 5G bands support (24–40 GHz), broadband spectrum, frequency agility, low 3 dB beamwidth, interference reduction, and medical application suitability, respectively. The proposed antennae also cover the desired mm wave 5G region with different resonating notches over ultra‐wide bandwidth, such as n257, n258, n259, n260, and n261, and ground‐based radio navigation applications. Results are validated with vector network analyzer, spectrum analyzer, and power sensor in the presence of absorber, respectively.

A novel multifunctional chiral metasurface with asymmetric transmission

The multiband, multifunctional chiral metasurface with asymmetric transmission exhibits significant potential for diverse applications in modern communication systems, ranging from enhanced signal modulation and polarization control to advanced beam steering and compact antenna design. This research presents a versatile and advanced chiral metasurface operating at multiple bands with diverse functionalities, including asymmetric transmission. The proposed metasurface effectively transforms an incoming Linearly Polarized (LP) wave into a Circularly Polarized (CP) wave. Additionally, it functions as a 90° polarization rotator for the incident LP wave. The design starts with an element of a 2 × 2 supercell comprising a Square Split Ring Resonator (SSRR) and an I-shaped resonator. The right diagonal elements of a supercell undergo scaling down, giving rise to a rotational asymmetry. Chirality is introduced into the design, and cross polarization conversion is enhanced by rotating all four elements by 90° relative to each other. On the back side of the substrate, each element undergoes a 90° rotation compared to its counterpart on the front side, realizing the asymmetric transmission feature. The incorporation of multiband and multifunctional features within a single supercell equips the subject chiral metasurface to be utilized in various engineering applications.

Enhanced Antipodal Vivaldi Antenna with SSRR metamaterial for improved 5G performance in the 38 GHz band

This study involves the integration of a compact Antipodal Vivaldi Antenna (AVA) with a square-shaped split ring resonator (SSRR) metamaterial to achieve improved performance, specifically in the 38 GHz band of 5G applications. The compact antenna is fabricated on Roger's substrate 5880 with 20 x 6 x 0.5 mm3 dimensions. The operational frequency ranges from 34 GHz to 43.8 GHz, catering to the specific needs of the 5G spectrum. To optimize the antenna's performance, corrugations are strategically introduced in the flares of the AVA, resulting in a notable improvement in the front-to-back ratio (FBR) by 18.35 dB. Additionally, square-shaped split ring resonators (SSRRs) are integrated into the AVA aperture, contributing to a gain enhancement of 4.6 dBi. The overall design achieves a gain ranging from 9.2 dBi to 10.4 dBi across the 38 GHz frequency band. The proposed AVA demonstrates good characteristics, with the highest front-to-back (FBR) value recorded at 20.4 dB at 40.6 GHz. The FBR consistently exceeds 15.6 dB throughout the specified frequency range. The antenna design is fabricated, simulated, and experimentally verified, affirming its suitability for compact 5G devices. The results indicate that the proposed miniaturized AVA, incorporating SSRR metamaterial and optimized flare corrugations, is an efficient candidate for compact 5G devices, offering enhanced gain and FBR over the desired frequency band.

A compact wideband filtering rectangular dielectric resonator antenna with U-shaped metal strips

ABSTRACT In this paper, a compact wideband filtering rectangular dielectric resonator antenna (RDRA) loaded with a pair of U-shaped metal strips is proposed. By using a slot-coupled feeding structure, a rectangular DR with a length–width ratio of 3:1 is selected to combine the resonant frequencies of the TE 111 and TE 121 modes to achieve the passband. Two pairs of transverse branches with different lengths are added to the longitudinal microstrip feeding line, and the TE 111 , TE 11+δ1 , and TE 121 modes are successfully excited to enhance the bandwidth. The short pair of transverse branches can generate a null high-frequency radiation. A pair of U-shaped metal strips is loaded at both ends of the top of rectangular DR, introducing a low-frequency radiation null. Both radiation nulls can be independently adjusted. A pair of rectangular grooves is etched inside rectangular DR to boost the impedance matching level. The proposed filtering RDRA has been fabricated and measured for verification. The measured relative impedance bandwidth is 22.67% (4.34–5.45 GHz). The measured average gain and peak gain are 7.19 dBi and 8.06 dBi, respectively. RDRA filtering has broad application potential in modern communications, such as the N79 band.

Compact high gain and high isolation AMC-coupled MIMO antenna for wideband 5G millimeter wave applications

Compact high gain and high isolation AMC-coupled MIMO antenna for wideband 5G millimeter wave applications

Development of a compact metasurface antenna with reconfigurable pattern through mode combination technique for 5G mm‐wave applications

Development of a compact metasurface antenna with reconfigurable pattern through mode combination technique for 5G mm‐wave applications

Highly isolated electrically compact UWB MIMO antenna for wireless communications applications

A multiple-input multiple-output Ultra-Wide Band (UWB) antenna with a compact size of 0.8λ x 0.7λ is proposed. The presented structure is constituted with patch geometry on a planar surface. The radiator consists of three counter U-shaped conducting strips united with a patch structure where two are positioned nearby and the third geometry covers the remaining conducting strips. A corrugated design has been created on a ground plane in which zigzag pattern slots are engineered to receive high isolation of more than 20 dB. The configured antenna radiates over a wide frequency spectrum of 3.10 GHz–11.85 GHz. It offers a fractional bandwidth of 195 % with a gain of 2.80 dBi, 3.08 dBi, and 2.72 dBi for targeted resonances. The antenna radiation patterns and MIMO diversity parameters are also presented. The acceptable values of ECC (<0.05 abs), MEG (−6 dB to −8 dB), CCL (<0.02 bits/sec/Hz) were found. The fabricated model was tested inside an anechoic chamber environment to receive the measured response with optimum accuracy through multiple iterations. The measured response shows a strong correlation with numerically computed responses finding the presented antenna suitable for WiMAX, WLAN (max protocol) and radar applications.

28/38 GHz compact rhombic-shaped antenna for future generations of mobile communications

ABSTRACT It is mandatory for the modern antennas to be designed to operate in the millimetre-wave (mm-wave) range of the electromagnetic spectrum for future generations of mobile communication requires multiband operation of a single antenna. The present work proposes a dual-band antenna to operate at 28 and 38 GHz . The design stages of the proposed antenna and examples of the parametric study performed to arrive at the final antenna design are demonstrated and discussed in detail. The proposed antenna is constructed as a main patch with parasitic element that is capacitively coupled to the main patch through a narrow slot. The main patch is a rhombic-in-shape and excited through a microstrip live with inset feed. This rhombic shaped patch antenna is originally designed to operate at 28 GHz . To achieve the dual-band operation, the geometry of the main patch is modified and is loaded by a parasitic element. The antenna is fabricated for experimental assessment through measurement of the antenna impedance, radiation patterns, maximum gain and radiation efficiency. The proper operation at 28 and 38 GHz is confirmed by experimental verification of the simulation results. Both the simulation and measurements show that the proposed antenna has 50 Ω -matched impedance over the frequency bands 27.7 − 28.4 GHz and 37.7 − 38.4 GHz . The proposed antenna has been designed to enhance the communications system performance when used in the mobile networks through noise rejection by limiting the operation within relatively narrow bands around the resonant frequencies. The values of the maximum gain obtained at 28 and 38 GHz are 6.98 and 8.8 dBi , respectively. The radiation efficiencies of the proposed antenna are 89 % and 87 % , respectively, and the total efficiency is also calculated.

A compact coupling-fed omnidirectional wideband filtering antenna with high selectivity

ABSTRACT This paper presents a compact coupling-fed omnidirectional wideband filtering antenna with high selectivity for modern wireless communication systems. The antenna integrates a coupling-fed driven patch with a symmetrical printed Г-shaped dipole, facilitating wideband performance and high selectivity through multiple coupling paths. Coupling-fed structure introduces radiation nulls (RNs), achieving an operating bandwidth of 54.5% for |S11| ≤ −10 dB and out-of-band suppression of −9 dB without requiring additional circuits. Simulations and experiments validate the antenna’s performance, demonstrating multiple resonant frequencies and consistent omnidirectional radiation patterns. Compared to traditional designs, it offers superior bandwidth and selectivity, making it suitable for integration into planar RF circuits in applications such as Wi-Fi 6, 5 G, and radar systems.

A compact wideband MIMO antenna with efficient isolation for S and C-bands applications

This work explored a wideband Multiple Input Multiple Output (MIMO) antenna that has a compact rectangular shape, a rectangular stair slot, and a C-shaped metamaterial for isolation improvement. A wideband antenna has been developed and fabricated to determine the effectiveness of a specified metamaterial. To get minimum mutual coupling, the C-shaped metamaterial is positioned between the two rectangular antennas. According to the simulation, the MIMO antenna operates between 2.61 GHz and 7.64 GHz (5.03 GHz). Peak gain of the designed MIMO antenna from 3.4 to 9.1 dB. The envelope correlation coefficient (ECC) is < 0.03, diversity gain (DG) is > 9.99, mean effective gain (MEG) is < − 3 dB, and channel capacity loss (CCL) 0.005 is accomplished. The measured and simulated outcomes are in close acceptance of the performance parameter. Thus, the designed MIMO antenna is ascendancy for S and C-band applications such as Wi-Fi, Satellite up and downlink, and 5G.

Wavelet-based arcing signal source localization algorithm using a compact multi-square microstrip antenna

Ensuring power system safety involves effective arc fault detection and localization. Existing devices struggle to differentiate between normal and abnormal conditions, especially in confined spaces, posing precision challenges. Strategically placing antennas around the arc helps detect electromagnetic radiation, even in limited areas, enabling valuable data collection for real-time monitoring. To address these challenges, this paper proposes integrating experimental work using a compact multi-square microstrip antenna and signal processing techniques. The study compares the effectiveness of two signal processing approaches: Discrete Wavelet Transform (DWT), and Continuous Wavelet Transform (CWT). These techniques separate genuine arc signals from background noise by identifying unique characteristics and isolating the dominant frequency. The Time of Arrival (ToA) is measured and used in Least Square and Gauss-Jordan Elimination methods to calculate the arc source location. The outcomes illustrate the precision of the proposed model in detecting and pinpointing arc source signals, with error margins ranging from 0.0615 to 0.0713 m for the CWT technique, 0.0688 to 0.0789 m for the DWT technique, and 0.0799 to 0.0844 m from the actual signal captured. These results hold promise for enhancing the integration of experimental approaches in assessing arcing conditions, thereby addressing challenges in insulation systems.

Design of Unit Cells-Based Metamaterial Antenna

Abstract Artificial metallic structures with simultaneous negative permittivity (ɛ) and permeability (µ) that result in a negative refractive index are known as metamaterials. It supports backward waves, i.e., group velocities and inside Metamaterial phase velocities are antiparallel, because of its negative index. The shortcomings of a regular patch antenna, such as low gain and efficiency, can be overcome with the help of this metamaterial antenna, which is helpful for wireless communication. The shortcomings of a regular patch antenna, such as low gain and efficiency, can be overcome with the help of this metamaterial antenna, which is helpful for wireless communication. The effort is justified by the proposal to use DNG (Double Negative) Metamaterials to create compact planar antennas. Additionally, it has peculiar features when compared to materials that are easily obtained because of its negative permeability and permittivity, which results in a negative refractive index. Owing to the unique characteristics of Metamaterials, the antenna achieves 3.768 dB, 53.76 % overall efficiency, and a 1.6 VSWR at 5 GHz frequency using a single unit cell. These results are excellent for wireless LANs and point-to-point communication. Additionally, a different metamaterial antenna with three unit cells produces superior results at 5 GHz frequency, with a return loss of -13.51 dB, a gain of 5.19.17 dB, and an overall efficiency of 92.50% at 2.4 GHz, the results are 4.1830 dB, 60.78%, and -14.51 dB, respectively.

Compact and high isolated microstrip patch antenna system for full-duplex/MIMO applications

This paper presents a two-port microstrip patch antenna system with compact size and high isolation for full-duplex and multiple-input-multiple-output (MIMO) applications. The proposed miniaturization approach is to employ compact microstrip patch antenna and decoupling network as well. Here, two quarter-wavelength patch antennas are arranged in the H-plane coupled configuration with element spacing of about 0.008 λ at the center operating frequency. Besides, a defected ground structure is chosen as the decoupling network, which doesn't require any additional space and contributes to significantly reducing the overall antenna dimensions. The final antenna design with compact size of 0.49 λ × 0.37 λ × 0.01 λ has operating band from 2.45 to 2.48 GHz, in which isolation is better than 30 dB and the maximum isolation is 42 dB. Besides, the proposed antenna also achieved comparable gain of 3.8 dBi and good diversity performance. In comparison with other related works, the proposed design has smallest overall size with extremely small element spacing while obtaining comparable isolation enhancement.

Embroidered textile antenna with dual‐band capability for body‐centric communication systems

AbstractThe integration of health monitoring and wearable antenna technologies has enhanced patient assessment and the provision of healthcare. Traditional health monitoring methods have evoked a surge in interest toward embroidered antennas as a viable solution for constant physiological monitoring in a noninvasive way. This study examines the performance of an embroidered wearable textile (EWT) antenna intended for breathing rate applications. The antenna is seamlessly integrated into a commercially available T‐shirt, extending the confines of “smart” textiles. The compact (45 mm × 26 mm) EWT antenna operates in 2.4 and 5.8 GHz with gains of 2.07 and 5.85 dBi, respectively. Crumpling and stretching analysis have also been investigated to ensure antenna's mechanical stability and reliability. Subsequently a specific absorption rate analysis has also been performed to quantify the radiation within specified limits.

Compact Amplitude-Monopulse Antenna for Joint Two-Dimensional Direction Finding and Sectorized Communications in the 2.4 GHz ISM Band

Compact Amplitude-Monopulse Antenna for Joint Two-Dimensional Direction Finding and Sectorized Communications in the 2.4 GHz ISM Band

Compact and Single-Fed Cavity-Cascaded Antenna Array With Horizontal Polarization Based on Microstrip Line

Compact and Single-Fed Cavity-Cascaded Antenna Array With Horizontal Polarization Based on Microstrip Line

A Study of Wideband and Compact Slot Antennas Utilizing Special Dispersive Materials

A Study of Wideband and Compact Slot Antennas Utilizing Special Dispersive Materials