Antenna Performance Research Articles

Moving Target Detection for Array Antennas in Varying Multipath Environments

Detecting moving targets remains a significant challenge in radar applications, particularly in dense multipath environments where signal complexities present formidable obstacles. However, the application of time reversal (TR) technology offers promising prospects for enhancing target detection capabilities. Utilizing this technology, we propose a detection algorithm tailored specifically for a moving target, designed exclusively for array antennas (AA) operating in dense multipath environments with dynamic channel variations. We establish an AA-TR signal model within this framework and derive the AA-TR likelihood ratio test (AA-TR-LRT) detector. To assess the effectiveness of our proposed approach, we also develop the AA conventional LRT (AA-C-LRT) detector as a comparative benchmark. Comprehensive numerical tests consistently verify the outstanding effectiveness of our detection algorithm, underscoring its precision in detecting moving targets, particularly in highly complex multipath scenarios with varying channels.

Low Sidelobe Level, High-Gain Patch Antennas Operating at Higher-Order Modes

Low Sidelobe Level, High-Gain Patch Antennas Operating at Higher-Order Modes

Improved Sparrow Search Algorithm for Rectangular Planar Array Synthesis

To optimize sparse rectangular planar array antennas under multiple constraints, including array aperture, number of elements, and minimum element spacing, an improved sparrow search algorithm (ISSA) is proposed. Initially, a position distribution matrix is generated using the Blackman window weighting method. The sparrow search algorithm (SSA) is then enhanced by incorporating Kent mapping for population initialization, which improves the initial population’s diversity. Additionally, the strategy for updating the discoverer’s position integrates elements from the sine cosine algorithm (SCA), along with a nonlinear sine learning factor, thereby enhancing global search capability. Finally, a crossover strategy is embedded into the SSA to refine the optimization accuracy by improving the search methodology used by the vigilantes. To verify the efficacy of our approach, we carried out simulation experiments. The results demonstrate that this method significantly enhances the performance of the array antenna by reducing the peak sidelobe level and minimizing the zero-trap depth. These findings validate the reliability and effectiveness of the suggested method.

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.

A novel artificial intelligence‐based antenna designing model for optimizing 5G mobile communication

AbstractAntenna designing involves the creation of devices to transmit or receive electromagnetic signals for various applications. It encompasses optimizing parameters such as size, shape, and frequency response to achieve desired performance characteristics, including signal strength, bandwidth, and efficiency, across diverse communication systems and frequencies. In this research, we intend to establish a novel artificial intelligence (AI)‐based antenna designing model for optimizing 5th generation (5G) mobile communication. We proposed Multi‐Objective Zebra Optimization (MOZO) to enhance 5G antenna design, aiming to minimize return loss () and maximize gain (G) concurrently. MOZO efficiently explores design space, offering Pareto‐optimal solutions that balance objectives. This approach ensures optimal antenna performance across the desired frequency range, advancing 5G communication efficiency. Our model enhances the functionality of a small, rectangular patch antenna designed for the 5G band, specifically operating at 30 GHz. Additionally, we conducted a comparative analysis between the performance of our optimized rectangular 5G antenna and several recently employed 5G‐millimeter wave (mmWave) antennas. This comparison sheds light on the efficacy and competitiveness of our optimized design within the 5G‐mmWave antenna landscape.

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.

ANN modeling for predicting muscle-implanted antenna performance for skin and fat thickness variations at 2.45 GHz

Abstract Implantable antenna is embedded in implantable medical devices to communicate with external world for continuous patient monitoring. The implantable antenna performance may vary with patients due to their different skin and fat thickness owing to their environment, location and concentration of collagen in skin, estrogen and testosterone concentration, age, diseases like obesity, Gottron syndrome etc. Estimation of IMA performance requires a proper description of its dependence on variable skin and fat thickness which is not studied extensively in previous related works. In this article, we have designed a muscle-implanted antenna at 2.45 GHz to examine its performance dependence on variable skin and fat thickness values. In this study, we have designed an artificial neural network (ANN) for prediction of antenna performance parameters at 2.45 GHz for wide range of skin and fat thickness variations. The designed ANN model can predict antenna performance with ∼0.99 % error. Here, accurate dependence analysis of radiation performance of implantable antenna in terms of S 11, realized gain, bandwidth and operating frequency on skin and fat thickness variations is performed which has not been studied yet and use of ANN in this field for accurate prediction is also a novel approach.

A SAW Wireless Passive Sensing System for Rotating Metal Parts

Passive wireless surface acoustic wave (SAW) sensors are very useful for on-site monitoring of the working status of machines in complex environments, such as high-temperature rotating objects. For rotating parts, it is difficult to realize real-time and continuous monitoring because of the unstable sensing signal caused by the continuous change of the relative position of the rotating part to the sensor and shielding of the signal. In our SAW sensing system, we propose a loop antenna integrated with the rotating part to obtain a stable sensing signal owing to its omnidirectional radiation pattern. Methodologies for determining the antenna dimension, system operating frequency, and procedures for designing a SAW sensor tag are discussed in this paper. By fully utilizing the influence of metal rotor on antenna performance, the antenna needs no impedance matching elements while it provides sufficient gain, which equips the antenna with nearly zero temperature drift at a wide temperature-sensing range. Experimental verification results show that this sensing system can greatly improve the stability of the sensing signal significantly and can achieve a temperature sensing accuracy of ~1 °C at different rotational speeds, demonstrated by the feasibility of the loop antenna for monitoring the working status of rotating metal parts.

Design and performance observation of U-shapedQuadpot multiband operated MIMO antenna structure for 5G and WLAN applications using FR4 substrate with high isolation

The multiband operated four port MIMO antenna structure is presented in the manuscript. The unique U-shaped radiating patch element is considered for the analysis. Multiple iterations are taken to finalize the shape of the best structure. The DGS and parasitic patch approach helps enhance MIMO antenna performance. Four parametric studies are performed to find the best structure, varying the patch's length, breadth, parasitic patch radius and DGS. The analysis of scattering response is considered to be over 1 GHz to 14 GHz for the observation of band response. The suggested design represents a reflection coefficient of −38.092 dB and a peak bandwidth of 5.78 GHz. The proposed design provides a peak isolation of 60 dB and a peak E-field of 1.80 × 104 V/m. Using an FR4 substrate, the structure's response is compared with the simulated and measured. The effectiveness of the MIMO structure is checked by observing the performance of diversity parameters. The ECC value is near zero, the Negative value of TARC, the CCL is less than 0.08, the DG is near 10 dB and the MEG value is zero. The response of all diversity parameters is within the allowable range. The presented design opens a new way to target 5G and WLAN-related applications.

On the applicability of low-cost GNSS antennas to precise surveying applications

Abstract This study addresses the scientific question of the applicability of low-cost antennas to the most precise GNSS applications. First of all, we inspect the implications of the availability and quality of low-cost antenna PCC models for precise positioning. From this point of view, we analyze the selected performance indicators of multi-constellation positioning with the representative set of low-cost mass-market GNSS receiver antennas. The processing strategy was based on the relative positioning model, considered the most reliable and precise one. To isolate the antenna-related errors from atmospheric propagation ones, we conducted an experiment based on an ultra-short baseline. As the main indications of low-cost antenna performance, we considered distance and height residuals, defined as the difference between benchmarks and the retrieved from GNSS measurements. We found that the low-cost antenna's PCV effect may significantly affect the final results. On the other hand, the results obtained using certain configurations of low-cost antennas were characterized by only slightly higher standard deviations and discrepancies with respect to benchmark values than those obtained with surveying or geodetic equipment. We identify several sets of low-cost antennas where distance residuals do not exceed 4 mm and height residuals do not exceed 6 mm, which shows the low-cost antenna performance comparable to those achieved using high-grade antennas. On this basis, we conclude that selected low-cost antennas can meet the requirements of high-precision surveying 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 Series of Ultra-low Permittivity ALaP4O12 (A = Li, Na, K) Metaphosphate Microwave Dielectric Ceramics for Ultra-wideband Dielectric Resonant Antenna Application.

The employment of ultra-low permittivity materials in the configuration of antennas has been demonstrated to augment the antenna bandwidth and diminish signal delay effectively. This study presents three ultra-low permittivity metaphosphate microwave dielectric ceramics (MWDCs). The ALaP4O12 (A = Li, Na, K) metaphosphate ceramics, which all belong to the monoclinic crystal system, exhibit extremely low permittivity (εr ≈ 5) and excellent quality factor (Q·f > 10,000 GHz) at a low sintering temperature (T < 950 °C). Terahertz time-domain spectroscopy indicates that the εr of ALaP4O12 at terahertz frequencies is comparable to that observed in the microwave band and its value remains stable over an extensive frequency range. Furthermore, the relationship between the crystal structure and the dielectric properties of ALaP4O12 has been analyzed through the lens of chemical bond theory. The highest Q·f value observed for LiLaP4O12 can be attributed to the high chemical bond strength and stability of its crystal structure. The lowest ionic polarizability per unit volume is exhibited by NaLaP4O12, which results in the lowest pore-corrected permittivity. The thermal expansion of the chemical bonds within KLaP4O12 is considerable, resulting in the highest coefficient of thermal expansion. Finally, the performance of a LiLaP4O12-based dielectric resonator antenna (DRA) excited by slot-coupled microstrip lines was designed and optimized by using different ceramic radius-to-height (RH) ratios. It was found that when the RH ratio of DRA reached 1.85, both the fundamental mode (HEM11δ) and the higher-order mode (HEM12δ) of DRA were simultaneously excited. The two modes overlap significantly, resulting in an ultra-wideband (UWB) of 46.8% (bandwidth = 7.93 GHz). Concurrently, the maximum radiation efficiency and gain of the DRA, obtained from the simulation, are 97.9% and 7.92 dBi, respectively. The findings of this study may inform the investigation of ultra-low permittivity phosphorus-based MWDCs and UWB DRAs.

Design and analysis of graphene-based PBG and EBG array antennas for wideband and multiband mm-wave applications

This paper presents a graphene-based PBG, EBG array antenna design with 40 × 40 mm2 dimensions for wide and multiband applications. The corporate CPW (Coplanar Waveguide) feeding technique is integrated with the ring, meander line, and periodic staircase with a slot pattern and augmented by conductive graphene for Electromagnetic Band Gap and Photonic Band Gap structures on the opposite side. This integration significantly enhances antenna performance, manifesting in superior radiation properties, increased gain, enhanced directivity, and resonating behavior with return loss of 16.4, 21.7, and 22.45 27.0, 25.3 dB in range of 24–25.25 GHz, 26.29–28.1 GHz, and 28.8–35.95 GHz and five bands with return loss of 26.1 , 21.1 , 22.2 , 31 , and 15.5 dB in range of 25.28–26.25, 28.1–29.4, 30.7–33.5, 34–35.5, 36.2–40.0 GHz that covers wideband and Multiband applications concerning PBG and EBG structures, respectively. Furthermore, the proposed antennae exhibit peak gains of 8 dBi at 26.53 GHz and 9 dBi at 32 GHz, corresponding 86.1% and 79.4% peak efficiencies and ensure robust circular polarization at resonating notches cover the mm-Wave 5G frequency bands n257, n258, n259, n260, and n261 for 5G applications, supporting ultra-fast data rates and low-latency communication with ground-based radio navigation applications.

Compensation of phased array antenna electrical performance based on improved genetic algorithm

Phased array antennas are frequently subjected to surface distortions due to environ-mental factors during operation. Such distortions can lead to a deterioration in the electrical performance of the phased array antenna. This study provides an in-depth analysis of the impact of array distortions on electrical performance indicators. An electronic compensation approach, employing an enhanced genetic algorithm, is proposed to mitigate the effects of these distortions. The conventional genetic algorithm has been augmented with an elimination mechanism to boost convergence. This method compensates for amplitude and phase by calculating each element's amplitude and phase of the excitation current, thereby enhancing the convergence performance. Simulations this approach, simulations of rectangular microstrip patch antennas are conducted to validate the effectiveness of this approach. The simulation outcomes reveal that the proposed method significantly improves the antenna's radiation pattern and all performance indicators, confirming its efficacy.

Novel High Efficiency V‐Band Pure TEM D‐PRGW Antenna for 5G mmWave Applications

ABSTRACTThis paper starts with the proposal of an enhanced version of a planar rectangular slot antenna fed by the quasi‐TEM printed ridge gap waveguide (PRGW), attended with a numerical study of a miniaturization procedure showing the limitations of the conventional PRGW‐based antennas. Then innovative solution is introducing a new miniaturized pure TEM wide‐band slot antenna utilizing double PRGW (D‐PRGW) technology; the proposed approach is self‐packaged and shows high potential for enhancing antenna performance, particularly in terms of bandwidth, gain, and compactness. This technology is featured with low loss, high performance, and compact size; it consists of surrounding the ridge area with a double layer of electromagnetic band gap (EBG) lattice instead of one to eliminate the surface waves effectively and keep the signal completely confined inside the ridge area with strict minimum rows of EBG. Therefore, a broad impedance matching bandwidth (|S11| ≤ −10 dB) of 33.33% is obtained from 50 to 70 GHz, which covers the unlicensed NR parts (n262; amp; n263) of the V band. Furthermore, the antenna achieves a peak gain of approximately 16 at 65 GHz while the overall efficiency remains above 90% across the entire operating frequency band. The high performance along with the compact size of this novel design makes it a good candidate for 5G wireless communications applications centered around 60 GHz.

Multifunctional Double Band Mesh Antenna with Solar Cell Integration for Communications Purposes

A dual band flexible antenna based on a circularly polarized modified meshed patch antenna design. This article focuses on some of the most pressing issues in small satellite applications. The antenna optimization and improvement of antenna performance, such as radiation efficiency. As is well known, circular polarization is immune to the Faraday rotation effect in the ionosphere and can thus prevent a 3-dB loss in geo-satellite communication. With the use of the software program Computer Simulation Technology (CST), the proposed circularly polarized modified meshed patch antenna has been created. Therefore, this article also presents a modified design of a circularly polarized meshed patch antenna to reduce the complexity of the antenna and decrease the size as much as it is capable. However, a meshed patch antenna can support a high communication data rate. The antenna architecture will theoretically be consistent with the installation of solar panels. The antenna utilizes a conductive copper as the core material and the substrate using flexible polyimide. The design antenna is very small, having an overall size of 30 * 30 mm when compared to other conventional non-transparent antenna operating at the same frequencies of 2.6, 3.5 GHz. The antenna that is proposed involves two meshed patch elements of same size but in various shapes. Finally, the proposed antenna is integrated into a solar cell by using the amorphous silicon thin film.

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 high gain microwave and millimeter-wave-based balanced antipodal Vivaldi antenna with a parasitic patch and a half-spherical shaped dielectric lens

This paper presented the design and performance analysis of a high-gain balanced antipodal Vivaldi antenna (BAVA) integrated with a parasitic patch and a half-spherical shaped dielectric lens, specifically designed for microwave and millimeter-wave applications. Constructed with a Teflon substrate (εr = 2.1, tanδ = 0.0002) and energized by a 50-ohm microstrip feedline, the innovative design incorporated a parasitic patch and three different types of dielectric lenses: half-circular, conical, and half-spherical shaped. The half-spherical dielectric lens significantly enhanced performance, achieving a gain of 20.54 dB, side lobe level (SLL) of -18.15 dB, and a maximum beam squint of 1.59 degrees. Additionally, it exhibited a 98% radiation efficiency, a front-to-back ratio of 31.75 dB, and a half-power beamwidth (HPBW) of 6.7 degrees. The incorporation of a parasitic patch and a half-spherical shaped dielectric lens enhanced the antenna's performance. Comparative analysis with existing antennas underscored the superiority of the proposed design, positioning it as a promising solution for microwave and millimeter-wave communication systems, radar, and sensing applications.

Designing of Inverted F Antenna and Utilizing of Blockchain in Vehicle Systems

Raed Daraghma, Eman Daraghmi, Yousef Daraghmi, Hacene FoThis paper is the first to integrate a blockchain system to improve the manufacturing efficiency and reliability of 5G F Inverted antennas. The recommended antenna is constructed from a single side of a premium aluminum conductor, the width of the radiator is 0.564 mm, the thickness of the conductor is 0.77 mm ground plane is 29.3 x 29.3 mm2 dimension. The antenna is designed to work at a frequency of 5.9 GHz, therefore it can be used for vehicle applications. It is designed to be inserted as an integrated antenna into an IOT device and is composed of Microstrip F shapes. Therefore, a rectangular Microstrip patch F antenna was built and its performance was examined in this work. 5.9 GHz is the antenna's resonance frequency range, which is suitable for vehicle applications. The simulation software for this work was Computer Simulation Technology (CST) software. Antenna performance was compared concerning gain, bandwidth, and return on loss. By enhancing the production efficiency and reliability of 5G Inverted F antennas, our study sets a new benchmark for the integration of blockchain and smart contract technologies, paving the way for ground-breaking advancements in manufacturing techniques. The relevance of creating an inverted F antenna for the Vehicle Systems environment is increased by this research. Typically, rod antennas are found in automobiles. However, the Vehicle Systems industry's requirements for meeting the demands of human resources with a variety of applications at different frequencies are not met by the rod antenna now in use. Because of their important characteristics, which include wideband matching, omnidirectional pattern, high efficiency, and compact size, microstrip patch Inverted F antennas are highly favored in the Vehicle Systems industry. uchal

Antenna Optimization Using Metamaterials

Abstract Metamaterials are artificial structures engineered to exhibit electromagnetic properties not found in natural materials. These materials offer a diverse range of characteristics, including negative refractive index, reverse radiation, and electromagnetic cloaking. These unique properties find applications in microwave and optical domains, enabling improvements in antenna performance, the design of microwave filters, and the creation of flat optical lenses, among others. This study focuses on utilizing metamaterials to enhance antenna performance by boosting gain, reducing mutual coupling between MIMO antennas, converting polarization, and decreasing radar cross-section (RCS). The primary performance metric considered in this investigation is gain enhancement.