Array Antenna Research Articles

Mayfly optimization algorithm: a review

This paper gives a review on the bio-inspired optimization methodology known as mayfly (MA) algorithm in order to resolve issues in optimization techniques. It is a newly formed meta-heuristic optimization algorithm that focuses on the movements of masculine and feminine mayflies. It is encouraged from flying behaviour also the methods of mating in mayflies. With the help of a realistic-world separate flow planning issue along with the coupling behaviour in numerous objective optimizations, the performance of the mayfly algorithm (MA) is well evaluated. Some of the implementations of this algorithm are discussed in this paper: Bearing fault diagnosis based on the mayfly algorithm, optimizing the performance of PEMFC, Covid diagnosis, wind speed optimization, improving the scheduling of solar wind speed using mayfly optimization, detecting fault in the wind turbine gearboxes, patterning in the array antennas with the help of optimization and so on .One of the main advantages of the MA is that it combines the other optimization algorithms namely swarm optimization (PSO) with the evolutionary optimizations (GA). The motion of the mayflies that resemble nuptial dance model along with the arbitrary flight helps in the improvement of the stability within the exploration and exploitation methods. In addition, allows escape from the community peak. All the above work reviewed shows promising results from the algorithm. More work can be carried out using this algorithm in future.

A cutting-edge broadband Camembert-inspired dielectric resonator antenna

This article introduces an innovative approach to significantly broaden the bandwidth of Cylindrical Dielectric Resonators. A four-element Camembert-Shaped Cylindrical Dielectric Resonator Antenna (CDRA) is presented, using an air gap separating the resonators to enhance the antenna bandwidth. The radiators, i.e., the DRA blocks, are made of high relative-permittivity ceramic material (εr = 25 & 30) and are excited by microstrip-line feed. The proposed methodology involves the strategic design of these resonators, incorporating dielectric materials to finely optimize the frequency response. Experimental validation demonstrates a remarkable improvement in bandwidth when compared to conventional methodologies. This novel technique holds immense promise for applications requiring wideband antennas. The demonstrated effectiveness of this approach not only addresses contemporary challenges but also opens up new avenues in antenna design, catering to the escalating demands of modern communication systems. In addition to the compact dimensions of the elementary radiating element, the separation distance between them, set at λ/4, enhances the array antenna overall size, and its gain is nearly 10 dBi. The proposed antenna covers cellular network applications such as UMTS mobile phone band around 2.1 GHz, as well as wireless DECT phone bands around 1.9 GHz, facilitating data transmission over short distances and beyond, with an impedance bandwidth of 20%.

Far-field pattern accuracy improvement in planar near-field measurement using infinitesimal dipole modeling

This paper discusses the challenges in accurately measuring the far-field performance of array antennas, which have become more complex and larger due to recent trends in increasing the number of elements and the antenna size. The far-field measurement method, which is a general method for measuring a radiation pattern in a far-field, is difficult to be utilized at a high frequency due to limitations in physical chamber size and difficulty in diagnosing an antenna. In order to improve these problems, a near-field measurement method is used as an alternative. Even though using a near-field measurement, the accuracy of the derived far-field pattern is reduced at low elevation angles due to zero-padding of data outside the measurement area. The integration of the near-field measurement with the source reconstruction is a promising approach to enhance the measurement limits of the far-field pattern analysis. This paper aims to extend the previous work to accurately predict the far-field radiation pattern, especially in the low elevation angles. The verification of the proposed method is performed for a standard gain horn and 4 by 4 patch array antennas, with and without beam steering.

Low-Profile Circularly Polarized HF Helical Phased Array: Design, Analysis, and Experimental Evaluation

This paper presents the design, development, and performance evaluation of a compact wideband phased array active helical antenna for monitoring HF interference. Traditional multi-element HF antenna designs are often subjected to size restrictions. The front-to-back ratio of the proposed circularly polarized phased array exceeds 20 dB across the operating range. This array enables the simultaneous monitoring of vertically and horizontally polarized signals, offering a practical alternative to larger antennas, particularly in space-constrained scenarios. Through advanced low-noise amplifier design, efficiency and bandwidth are optimized while mitigating mutual coupling effects. Optimal beamformer design enhances array performance with respect to more traditional array design approaches. The test results verify exceptional performance with an average axial ratio of 2 dB and a high front-to-back ratio beyond the desired frequency range. This study offers valuable insights into the design and deployment of compact wideband phased array antennas, providing an effective solution for monitoring HF interference.

Compact fully metallic multi‐mode waveguide antenna for cellular communications

AbstractThe needed isolation between elements for high‐performance beam steering array antennas is a challenging task especially when the distance between the antenna elements is reduced. To tackle this problem, the authors report a multi‐port multi‐mode single‐antenna with beam steering capability (±7 deg) suitable for cellular communications. The multi‐port multi‐mode characteristic of the proposed antenna enables size reduction and better taper efficiency than antenna arrays operating in the 3.3–3.7 GHz cellular band. The reported antenna exploits four Transverse Electric modes to modify the half‐power beamwidth of the radiation from 20° to 41° as required in cellular communication.

Secured THz communication in photonic microcell networks based on spatial wave mixing of steered beams

Future 6G communication systems are envisioned to expand their carrier frequency to the THz region, where a broad unexplored region of spectrum is available. With this expansion, THz wireless communication has the potential to achieve ultra-high data transmission rates of up to 100Gbit/s. However, as large amounts of data are transmitted in an open wireless environment, there are significant concerns regarding communication security due to the susceptibility to eavesdropping, interception, and jamming. In this work, we proposed a secure approach for THz wireless communication based on spatial wave mixing and flexible beam steering. To achieve this, two frequency-modulated THz waves, which are generated by photonic THz sources and carry encrypted information with true randomness, are mixed at a THz envelope detector with an exclusive-OR logic operation. We analyzed the possible spatial location for the THz detector to ensure a secure microcell network deployment. Our results demonstrate that the size of the decryptable region is directly dependent on the directivity and width of the emitted THz beam. To address this, we have developed an array antenna with integrated uni-traveling-carrier photodiodes (UTC-PDs), which is capable of generating THz waves while also improving the flexibility of beam pointing, allowing for greater control over the location and size of the decodable region. By controlling fiber-optic delay lines, we successfully demonstrated that the directional gain of a 200GHz wave is increased by 8dB through a 1 × 3 UTC-PD-integrated planar bowtie antenna (PBA) array, together with continuous beam steering from -20° to 10°. Additionally, using a 1 × 4 UTC-PD-integrated PBA array to emulate two encryption transmitters and a Femi-level managed barrier diode to detect spatially mixed THz waves, we successfully achieved a feasibility experiment for real-time 200Mbit/s location-based decryption in the 200GHz band. These results indicate that the proposed scheme is feasible for secured THz communication, and would be a powerful candidate to mitigate security risks in 6G microcell networks.

Method of constructive synthesis of a flat active phased array antenna with a limited number of active channels

A method of constructive synthesis of a flat active phased array antenna from linear horizontal sublattices with an unequal number of antenna elements and the number of active channels equal to the number of sublattices is proposed. The transmission coefficients of the active channels, the number of elements in the sublattices and the coordinates of the placement of the phase centers of the sublattices of the active phased array antenna array in a flat opening are considered as the desired parameters of the constructive synthesis problem. Restrictions are set on the shape of the boundary of the flat opening and the amplitude distribution in the opening of the active phased array antenna. The requirements for the scanning sector of the active phased array antenna are formulated. The method is based on an iterative procedure. In the process of its implementation, the deviation of the amplitude distribution in the opening of the active phased array antenna from the sublattices from the specified amplitude distribution is minimized. The method has shown its efficiency in the formation of various amplitude distributions in the AFAR opening. The stability of the problem solution to external influences, including in the event of failures of antenna elements, is estimated. The solutions obtained can be used in monopulse radar stations with mechanical beam scanning in the azimuthal plane and electronic scanning in the angular plane.

The main directions of enhancement of digital antenna arrays

The development of modern radio electronic systems causes an increase in the requirements for the parameters of antenna devices (AU) and causes the transition from previously used mirror antennas and passive phased array antennas (FAA) to active FAA (AFAA), the considerable advantage of which is a significant reduction in energy losses of transmitted and received signals by reducing the distance of the low-noise amplifier input and output of power amplifier to the antenna element. Further development of the AU is the transition from AFAA with analog beamforming to digital antenna arrays (DAR) with digital beamforming, the advantages of which are due to the possibility of forming multibeam receiving and transmitting radiation patterns with independent control of the direction and shape of the beams, as well as the possibility of flexible change of operating modes. The use of a DAR with two-dimensional electronic scanning provides a significant increase in the efficiency of radio-electronic systems. Thus, their use in radar provides a gain in the efficiency of using the time, energy, frequency and spatial resources of radar with CAR up to 13 times compared with radar with passive FAA and AFAA with one-dimensional scanning. The disadvantages of the DAR are the high cost and increased energy consumption due to the installation of active elements in each transceiver channel, as well as the long time required to create new products, associated with a large amount of software and a complex structure for building a CAR. To overcome these disadvantages, manufacturers of antenna arrays and developers of the radio-electronic element base are creating new technical solutions. The main directions of development of technologies for the production of DAR functional devices that reduce the cost and reduce the time needed to create new products are shown: the development of common modules that allow you to create scalable DAR, increasing the integration of microwave monolithic integrated circuits with the placement of the maximum number of transceiver channels on one chip, increasing the integration of ASIC, including ADCs, DACs and digital signal processing devices, increasing the clock frequencies of digital functional nodes, as well as the development of circuit solutions for building nodes with low energy consumption.

Small-sized active phased array antenna for base stations of mobile radio networks in limited deployment conditions

Today, most telecommunications structures are oversaturated with antenna technology. There is a need to use high-rise buildings and facilities that are not equipped for communication. However, the use of such objects imposes a number of restrictions on the installation locations of antenna systems. Thus, the problem arises of developing an antenna system that makes it possible to achieve a circular radiation pattern using small-sized antennas. A model of a small-sized UHF AFAR has been developed. A distinctive feature of this AFAR is the use of a ring active phased antenna array with an electrically controlled radiation pattern as an antenna system. Such solutions have not been used in domestic antenna technology, including military radio communications. The antenna complex is proposed to be used for installation on mobile objects, as well as on the upper platforms of towers and masts to provide a circular radiation pattern in places where it is impossible to implement a ring antenna array around the perimeter of the object.

Design and Fabrication of Compact MIMO Array Antenna with Tapered Feed Line for 5G Applications

In this paper, we design, fabricate, measure, and report two proposed multiple input multiple output antenna elements (MIMOs) with good performance in the 5G band. The MIMO antennas are mounted on Roger / Druoid 5880 substrates (dielectric constant: 2.2) with an overall structure volume 20×24.14×0.79mm3. First, a comprehensive parametric study is performed based on CST Electromagnetic (EM) Simulator to investigate and enhance the antenna performance in relation to 5G application requirements. Second, as part of the antenna design process, we compute the envelope correlation coefficient (ECC > 0.01dB) and diversity gain (DG> 9.9dB) and achieve good results. Third, we provide fabrication and measurement verification with good agreement. Fourth, we use a tapered feed structure with inset feed to minimize mutual coupling and achieve matching along 2 transmission lines with various impedances with high compactness in the antenna structure. Fifthly, we report that the proposed antenna structure has a gain is 8 dBi (dB) at the relevant operating frequency band (24.25

Design and optimization of a dual port high gain circularly polarized graphene-ceramic array antenna in a THz regime

In this paper, a dual port high gain hybrid (silicon graphene) antenna is designed and investigated. Some of the important qualities of the proposed radiating structure include the following: (1) XGBoost and Random Forest-based machine learning (ML) techniques are applied to predict the reflection coefficient (|S11|) features of the designed radiator to reduce the simulation time; (2) the use of a cross slot provides the circularly polarized waves between 4.92 and 5.38 THz; (3) a 1∗2 array structure produces the high gain, i.e., 10.0 dBi within the operating frequency range; and (4) the opposite orientation of the aperture provides a polarization diversity concept, which, in turn, improves the isolation level to more than 30 dB. After comparing the results obtained from CST and HFSS, as well as those predicted from the ML algorithm, it is confirmed that the designed radiator operates from 4.71 to 5.85 THz. The good value of far-field and diversity parameters affirms the fitness of the designed radiator for wireless power transfer in the THz regime.

Design of higher gain linearly polarized 2×2 microstrip patch array antenna for wireless communication

The fifth-generation technology is popular and best as far as data rates are concerned for wireless applications. To meet the increased demand of the modern world for faithful communication, this research work is carried out. In this approach, a single patch, 1×2 array, and 2×2 array are designed using a low-cost FR4 dielectric substrate ( =4.4) covering the 3.3–3.8 GHz frequency band. Due to the lack of gain from arrays in the present research, an attempt is made to achieve excellent gain from arrays with a minimum number of patches. First, the gain of a single inset-fed antenna is compared with another normal single patch of the same thickness but with an additional air dielectric medium. Next, the second single patch is extended to obtain a rectangular 1×2 array and a 2×2 array antenna. A second single patch measuring 50×32.5×0.8 mm is designed assuming an infinite ground plane. It has 3mm air gap between the patch strip and the ground. Air acts as a second dielectric layer that reduces power loss. This allows a maximum gain of 15.2 dB with a return loss of -22 dB. Also, antenna efficiency and bandwidth are 91% and 267.69 MHz, respectively.

Design and Development of Dual Band Millimeter Wave Substrate Integrated Waveguide Antenna Array

Abstract New communication paradigms have emerged to make better use of the available wireless spectrum due to its scarcity. Millimeter wave high-frequency spectrum could offer a viable solution to the problem of spectrum scarcity. Millimeter wave devices and antennas are becoming increasingly popular and are used in a wide variety of applications and planned Fifth Generation (5G) wireless communication networks. In this work, we develop a Substrate Integrated Waveguide (SIW) based antenna array and millimeter-wave feeding network with the aim of achieving optimal performance. A microstrip array antenna is developed for use at millimeter wave frequencies of 28 GHz and 38 GHz. Next, an SIW array antenna will be created. For high-frequency uses, SIW technology excels due to its low loss, easy integration and high quality factor. The two unequal longitudinal slots in a slotted SIW antenna cause the structure to resonate at 28 GHz and 38 GHz. The SIW structure is fabricated by making two parallel rows of metallic vias, carefully determined through sizes to ensure minimal internal losses. A microstrip line that transitions into a SIW feeds into the proposed layout. In this paper, the authors investigate the design and construction of an integrated waveguide antenna array for use at dual millimeter-wave frequencies.

Design of a Microwave/Millimeter-Wave Shared-Aperture Antenna by Hybridizing Series-Fed Antenna Array and Leaky Wave Antenna

Design of a Microwave/Millimeter-Wave Shared-Aperture Antenna by Hybridizing Series-Fed Antenna Array and Leaky Wave Antenna

Heterogeneous Beam Elements Based Phased Array Antenna Technology: Theory, Analysis, and Experiment

Heterogeneous Beam Elements Based Phased Array Antenna Technology: Theory, Analysis, and Experiment

Design of Dual-Polarized Tilted-Beam Parasitic Array Antenna With Both High Isolation and High Polarization Purity

Design of Dual-Polarized Tilted-Beam Parasitic Array Antenna With Both High Isolation and High Polarization Purity

Phased Array Antenna With Top-Truncated Dome Lens for Wide-Angle Scanning

Phased Array Antenna With Top-Truncated Dome Lens for Wide-Angle Scanning

Miniaturized wide‐band microstrip grid array antenna loaded with slow‐wave transmission line

AbstractA miniaturized microstrip grid array antenna (MGAA) in X‐band is proposed in the paper. The antenna consists of a radiation grid array, a feed network and a metal back cavity. The 2 × 2 planar grid array is constructed by using four MGAAs as subarrays. MGAA does not require complex feeders in contrast to microstrip patch arrays. Furthermore, a curved slow‐wave transmission line (SWTL) is adopted as the long side of grid. The SWTL not only reduces the physical size of the grid while keeping its electrical size unchanged, but also improves the impedance matching and greatly broaden the bandwidth of the antenna. A fabricated prototype was measured in the microwave chamber. The results indicate that the impedance matching band of |S11| < −10 dB is from 9 to 10.5 GHz (15.4%), and the maximum gain is 19.2 dBi. Meanwhile, the projected area of the antenna is reduced by about 40% by loading the SWTL.

Single-Layer Dual-Polarized Endfire Phased Array Antenna for 5G mm-Wave Mobile Terminals

Single-Layer Dual-Polarized Endfire Phased Array Antenna for 5G mm-Wave Mobile Terminals

A Wideband Conformal Array Antenna With Dual-Polarized Transmission and Reflection Element for Full-Space Beam-Scanning Capability

A Wideband Conformal Array Antenna With Dual-Polarized Transmission and Reflection Element for Full-Space Beam-Scanning Capability