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19 pages, 5680 KiB

Open AccessArticle

Optimization Environment Definition for Beam Steering Reflectarray Antenna Design

by Alessandro Niccolai, Francesco Grimaccia, Marco Mussetta, Riccardo Zich and Alessandro Gandelli

Mathematics 2022, 10(1), 33; https://doi.org/10.3390/math10010033 - 23 Dec 2021

Cited by 3 | Viewed by 3055

Abstract

Reflectarray antennas are low-profile high-gain systems widely applied in the aerospace industry. The increase in their application is leading to the problem of getting more advanced performance while keeping the system as simple as possible. In these cases, their design cannot be conducted [...] Read more.

Reflectarray antennas are low-profile high-gain systems widely applied in the aerospace industry. The increase in their application is leading to the problem of getting more advanced performance while keeping the system as simple as possible. In these cases, their design cannot be conducted via analytical methods, thus evolutionary optimization algorithms are often implemented. Indeed, the design is characterized by the presence of many local minima, by high number of design variables, and by the high computational burden required to evaluate the antenna performance. The purpose of this paper is to develop, implement, and test a complete Optimization Environment that can be applied to achieve high scanning capabilities with a reflectarray. The design of the optimization environment has been selected to be flexible enough to be applied also with other different algorithms. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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23 pages, 1037 KiB

Open AccessArticle

Feasible Optimal Solutions of Electromagnetic Cloaking Problems by Chaotic Accelerated Particle Swarm Optimization

by Alkmini Michaloglou and Nikolaos L. Tsitsas

Mathematics 2021, 9(21), 2725; https://doi.org/10.3390/math9212725 - 27 Oct 2021

Cited by 7 | Viewed by 2149

Abstract

The optimization problem of cloaking a perfectly electric conducting or dielectric spherical core is investigated. The primary excitation is due to an external magnetic dipole. The chaotic accelerated particle swarm optimization (CAPSO) algorithm is adjusted and applied to this optimization problem. The optimization [...] Read more.

The optimization problem of cloaking a perfectly electric conducting or dielectric spherical core is investigated. The primary excitation is due to an external magnetic dipole. The chaotic accelerated particle swarm optimization (CAPSO) algorithm is adjusted and applied to this optimization problem. The optimization variables are the radii, the permittivities and the permeabilities of a small number of spherical shells covering the core. Several feasible optimal designs are obtained, which exhibit perfect or almost perfect cloaking performance for all angles of observation. These optimal designs correspond to two, three or four spherical coating layers composed of ordinary materials. Detailed parametric investigations of the cloaking mechanism with respect to the type and radius of the core and the location of the primary dipole are carried out. The presented optimization procedure and the reported results are expected to be useful in applications like scattering and characterization of optical particles as well as in designing low-profile receiving antennas. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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28 pages, 4053 KiB

Open AccessArticle

Novel Design Framework for Dual-Band Frequency Selective Surfaces Using Multi-Variant Differential Evolution

by Achilles D. Boursianis, Maria S. Papadopoulou, Spyridon Nikolaidis, Panagiotis Sarigiannidis, Konstantinos Psannis, Apostolos Georgiadis, Manos M. Tentzeris and Sotirios K. Goudos

Mathematics 2021, 9(19), 2381; https://doi.org/10.3390/math9192381 - 25 Sep 2021

Cited by 5 | Viewed by 2949

Abstract

Frequency Selective Surfaces (FSSs) have become increasingly popular during the last years due to their combined characteristics, which meet, in general, the requirements of the next-generation wireless communication networks. In this work, a cross-platform design framework for FSS structures is presented and evaluated [...] Read more.

Frequency Selective Surfaces (FSSs) have become increasingly popular during the last years due to their combined characteristics, which meet, in general, the requirements of the next-generation wireless communication networks. In this work, a cross-platform design framework for FSS structures is presented and evaluated by utilizing a recently introduced evolutionary optimization algorithm, namely, the Multi-Variant Differential Evolution (MVDE). To the best of the authors knowledge, this is the first time that the MVDE algorithm is applied to a design problem in Electromagnetics. The proposed design framework is described in detail and the utilized evolutionary algorithm is assessed in terms of its performance by applying several benchmark functions. In this context, the MVDE is comparatively evaluated against other popular evolutionary algorithms. Moreover, it is applied to the design and optimization of two different representative examples of FSS structures based on three use cases of unit cell geometry. Optimization results indicate the efficacy of the proposed framework by quantifying the performance of the designed FSS structures in terms of several system metrics. The optimized FSS structures exhibit dual-band operation and quite acceptable results in the ISM frequency bands of 2.45 GHz and 5.8 GHz. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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13 pages, 3751 KiB

Open AccessArticle

The Design of a Wideband Antenna with Notching Characteristics for Small Devices Using a Genetic Algorithm

by Wahaj Abbas Awan, Abir Zaidi, Musa Hussain, Niamat Hussain and Ikram Syed

Mathematics 2021, 9(17), 2113; https://doi.org/10.3390/math9172113 - 1 Sep 2021

Cited by 27 | Viewed by 4100

Abstract

This paper presents the design and realization of a compact printed ultra-wideband (UWB) antenna with notching characteristics for compact devices using a genetic algorithm. The antenna is capable of mitigating an adjacent sub-band ranging from 3.75 to 4.875 GHz, mainly used by many [...] Read more.

This paper presents the design and realization of a compact printed ultra-wideband (UWB) antenna with notching characteristics for compact devices using a genetic algorithm. The antenna is capable of mitigating an adjacent sub-band ranging from 3.75 to 4.875 GHz, mainly used by many applications and standards such as WiMAX, WLAN and sub-6-GHz. The notch band functionality is achieved by etching out two symmetrical slots from the pentagonal radiating element. The simulation and measured results demonstrate that the proposed antenna overperformed compared with state-of-the-art antennas in terms of compactness with an overall size of

20 mm \times 15 mm \times 0.508 mm

. Moreover, the proposed design shows a large bandwidth in the UWB region with a fractional bandwidth of 180% with respect to the center frequency of 5.25 GHz. The antenna also presents omnidirectional radiations all over the operation band and a good return loss performance. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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8 pages, 800 KiB

Open AccessArticle

A Compact Octa-Band Frequency Reconfigurable Antenna for Wireless Applications

by Adnan Ghaffar, Wahaj Abbas Awan, Niamat Hussain and Xue-Jun Li

Mathematics 2021, 9(13), 1557; https://doi.org/10.3390/math9131557 - 2 Jul 2021

Cited by 9 | Viewed by 2758

Abstract

This paper presents the design and realization of a compact frequency reconfigurable antenna for multiband wireless applications. The antenna can operate at overall eight different bands in four dual-band modes. A slot in the radiator and defected ground structure are utilized to achieve [...] Read more.

This paper presents the design and realization of a compact frequency reconfigurable antenna for multiband wireless applications. The antenna can operate at overall eight different bands in four dual-band modes. A slot in the radiator and defected ground structure are utilized to achieve a compact size, while PIN diodes are used for frequency reconfigurability in the proposed antenna. The antenna shows broad bandwidth in each operating frequency and has a compact size of 18 mm × 18 mm × 1.524 mm. Moreover, stable radiation patterns and a high value of efficiency make it a potential candidate for various wireless applications. Furthermore, to demonstrate the worth of this work, its performance is compared with state-of-the-art designs reported for similar applications. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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22 pages, 27660 KiB

Open AccessArticle

A Modified Rao-2 Algorithm for Optimal Power Flow Incorporating Renewable Energy Sources

by Mohamed H. Hassan, Salah Kamel, Ali Selim, Tahir Khurshaid and José Luis Domínguez-García

Mathematics 2021, 9(13), 1532; https://doi.org/10.3390/math9131532 - 29 Jun 2021

Cited by 40 | Viewed by 3697

Abstract

In this paper, a modified Rao-2 (MRao-2) algorithm is proposed to solve the problem of optimal power flow (OPF) in a power system incorporating renewable energy sources (RES). Quasi-oppositional and Levy flight methods are used to improve the performance of the Rao algorithm. [...] Read more.

In this paper, a modified Rao-2 (MRao-2) algorithm is proposed to solve the problem of optimal power flow (OPF) in a power system incorporating renewable energy sources (RES). Quasi-oppositional and Levy flight methods are used to improve the performance of the Rao algorithm. To demonstrate effectiveness of the MRao-2 technique, it is tested on two standard test systems: an IEEE 30-bus system and an IEEE 118-bus system. The objective function of the OPF is the minimization of fuel cost in five scenarios. The IEEE 30-bus system reflects fuel cost minimization in three scenarios (without RES, with RES, and with RES under contingency state), while the IEEE 118-bus system reflects fuel cost minimization in two scenarios (without RES and with RES). The achieved results of various scenarios using the suggested MRao-2 technique are compared with those obtained using five recent techniques: Atom Search Optimization (ASO), Turbulent Flow of Water-based Optimization (TFWO), Marine Predators Algorithm (MPA), Rao-1, Rao-3 algorithms, as well as the conventional Rao-2 algorithm. Those comparisons confirm the superiority of the MRao-2 technique over those other algorithms in solving the OPF problem. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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29 pages, 3934 KiB

Open AccessArticle

Parameter Estimation of Induction Machine Single-Cage and Double-Cage Models Using a Hybrid Simulated Annealing–Evaporation Rate Water Cycle Algorithm

by Martin Ćalasan, Mihailo Micev, Ziad M. Ali, Ahmed F. Zobaa and Shady H. E. Abdel Aleem

Mathematics 2020, 8(6), 1024; https://doi.org/10.3390/math8061024 - 23 Jun 2020

Cited by 31 | Viewed by 4072

Abstract

This paper presents the usage of the hybrid simulated annealing—evaporation rate water cycle algorithm (SA-ERWCA) for induction machine equivalent circuit parameter estimation. The proposed algorithm is applied to nameplate data, measured data found in the literature, and data measured experimentally on a laboratory [...] Read more.

This paper presents the usage of the hybrid simulated annealing—evaporation rate water cycle algorithm (SA-ERWCA) for induction machine equivalent circuit parameter estimation. The proposed algorithm is applied to nameplate data, measured data found in the literature, and data measured experimentally on a laboratory three-phase induction machine operating as an induction motor and as an induction generator. Furthermore, the proposed method is applied to both single-cage and double-cage equivalent circuit models. The accuracy and applicability of the proposed SA-ERWCA are intensively investigated, comparing the machine output characteristics determined by using SA-ERWCA parameters with corresponding characteristics obtained by using parameters determined using known methods from the literature. Also, the comparison of the SA-ERWCA with classic ERWCA and other algorithms used in the literature for induction machine parameter estimation is presented. The obtained results show that the proposed algorithm is a very effective and accurate method for induction machine parameter estimation. Furthermore, it is shown that the SA-ERWCA has the best convergence characteristics compared to other algorithms for induction machine parameter estimation in the literature. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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Review

Jump to: Research

16 pages, 9130 KiB

Open AccessReview

Enhancing Gain for UWB Antennas Using FSS: A Systematic Review

by Ahmed Jamal Abdullah Al-Gburi, Imran Mohd Ibrahim, Zahriladha Zakaria, Muhannad Kaml Abdulhameed and Tale Saeidi

Mathematics 2021, 9(24), 3301; https://doi.org/10.3390/math9243301 - 18 Dec 2021

Cited by 48 | Viewed by 7314

Abstract

This review paper combs through reports that have enhanced antenna gain for ultra-wideband (UWB) frequencies using frequency-selective surface (FSS) techniques. The FSS techniques found across the research landscape were mapped onto a taxonomy in order to determine the most effective method for improving [...] Read more.

This review paper combs through reports that have enhanced antenna gain for ultra-wideband (UWB) frequencies using frequency-selective surface (FSS) techniques. The FSS techniques found across the research landscape were mapped onto a taxonomy in order to determine the most effective method for improving antenna gain. Additionally, this study looked into the motivation behind using FSS as a reflector in UWB frequencies to obtain directional radiation. The FSS suits multiple applications due to its exceptional ability to minimize power loss in undesired transmission areas in the antenna, as well as to hinder the interference that may occur from undesirable and wasted radiation. An efficient way to obtain constant gain over a wide range of frequencies is also elaborated in this paper. Essentially, this paper offers viable prescription to enhance antenna gain for UWB applications. Methods: A comprehensive study was performed using several imminent keywords, such as “high gain using FSS”, “gain enhancement using FSS”, “high gain UWB antennas”, and “gain enhancement of UWB antennas”, in different modifications to retrieve all related articles from three primary engines: Web of Science (WoS), IEEE Xplore, and Science Direct. Results: The 41 papers identified after a comprehensive literature review were classified into two categories. The FSS single- and multi-layer reflectors were reported in 25 and 16 papers, respectively. New direction: An effective method is proposed for FSS miniaturization and for obtaining constant gain over UWB frequencies while maintaining the return loss at −10 dB. Conclusion: The use of FSS is indeed effective and viable for gain enhancement in UWB antennas. This systematic review unravels a vast range of opportunities for researchers to bridge the identified gaps. Full article

(This article belongs to the Special Issue Evolutionary Optimization Algorithms for Electromagnetic Devices)

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