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Electronics, Volume 11, Issue 5 (March-1 2022) – 164 articles

Cover Story (view full-size image): In general, The PV monitoring system sustainably provides real-time data and status information about PV modules and PCSs. PV monitoring technology using short-range wireless communication technology has been developed. LoRa is a representative technology of low-power long-distance communication and provides a very wide communication range with low power. This enables long-distance, low-power wireless network monitoring without charging additional costs. A monitoring system consisting of LoRa could be an innovative development strategy for building micro-networks in residential and commercial buildings. Overall, there is a trend toward strengthening the construction of smart homes, including improving the energy efficiency of houses and disseminating monitoring. View this paper
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24 pages, 4085 KiB  
Article
A Smart Information System for Passengers of Urban Transport Based on IoT
by Hugo Estrada-Esquivel, Alicia Martínez-Rebollar, Pedro Wences-Olguin, Yasmin Hernandez-Perez and Javier Ortiz-Hernandez
Electronics 2022, 11(5), 834; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050834 - 07 Mar 2022
Cited by 3 | Viewed by 3359
Abstract
Several developed countries have implemented smart systems for public transport that provide mobility services for citizens. Most of these systems use special infrastructures to determine the location of citizens and public buses. However, the implementation of these systems does not take into account [...] Read more.
Several developed countries have implemented smart systems for public transport that provide mobility services for citizens. Most of these systems use special infrastructures to determine the location of citizens and public buses. However, the implementation of these systems does not take into account the poor infrastructure of developing countries. In Mexico, Urban Passenger Transport has insufficient transport units to meet the demand of passengers who move throughout the day, and these do not consider hardware infrastructure. Our solution is focused on inexpensive devices that are accessible to citizens, such as mobile phones. In this research work, a smart information system for passengers of urban transport is presented that allows passengers to know the expected arrival times and also to know the availability of seats on the bus that is heading towards their position. The solution was evaluated with real routes, and the results are promising for a pilot project to be put in practice. Full article
(This article belongs to the Topic Intelligent Transportation Systems)
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9 pages, 3878 KiB  
Article
Low Power Consumption Gate-Tunable WSe2/SnSe2 van der Waals Tunnel Field-Effect Transistor
by Abdelkader Abderrahmane, Changlim Woo and Pil-Ju Ko
Electronics 2022, 11(5), 833; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050833 - 07 Mar 2022
Cited by 2 | Viewed by 2145
Abstract
Two-dimensional (2D) transition-metal dichalcogenides (TMDCs) have attracted attention as promising next-generation electronic devices and sensors. In this study, we fabricated a novel nanoelectronic device based on a black-phosphorus-gated WSe2/SnSe2 van der Waals (vdW) tunnel field-effect transistor (TFET), where hexagonal boron [...] Read more.
Two-dimensional (2D) transition-metal dichalcogenides (TMDCs) have attracted attention as promising next-generation electronic devices and sensors. In this study, we fabricated a novel nanoelectronic device based on a black-phosphorus-gated WSe2/SnSe2 van der Waals (vdW) tunnel field-effect transistor (TFET), where hexagonal boron nitride (h-BN) was used as the gate insulator. We performed morphological, electrical, and optoelectronic characterizations. The p-WSe2/n-SnSe2 heterostructure-based TFET exhibited p-type behavior with a good dependence on the gate voltage. The TFET device showed a trend toward negative differential resistance (NDR) originating from band-to-band tunneling, which can be tuned by applying a gate voltage. The optoelectronic performance of the TFET device was low, with a maximum photoresponsivity of 11 mA W−1, owing to the large device length. The results obtained herein promote the integration of black phosphorus into low-energy-consumption 2D vdW TFETs. Full article
(This article belongs to the Section Semiconductor Devices)
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21 pages, 3507 KiB  
Article
Toward Efficient Blockchain for the Internet of Vehicles with Hierarchical Blockchain Resource Scheduling
by Liming Gao, Celimuge Wu, Zhaoyang Du, Tsutomu Yoshinaga, Lei Zhong, Fuqiang Liu and Yusheng Ji
Electronics 2022, 11(5), 832; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050832 - 07 Mar 2022
Cited by 9 | Viewed by 2270
Abstract
With the development of advanced information and communication technology, the traditional centralized cloud architecture cannot satisfy the exploding demand for data exchange in Internet of Vehicle (IoV) systems. Moreover, the traditional centralized architecture of the vehicular network has the potential risk of a [...] Read more.
With the development of advanced information and communication technology, the traditional centralized cloud architecture cannot satisfy the exploding demand for data exchange in Internet of Vehicle (IoV) systems. Moreover, the traditional centralized architecture of the vehicular network has the potential risk of a single point of failure and lacks autonomy since the system highly relies on a trusted third party (TTP) to provide identity management. Fortunately, the emergence of blockchain technology provides a potential direction to address these problems. However, there are still some problems existing in the construction of an efficient blockchain system in IoV systems, such as the dynamic network topology and limited resources. In this paper, we propose a hierarchical resource scheduling scheme for blockchain-enabled IoV systems that improves the performance of the blockchain-enabled IoV system by efficiently allocating computational resources. The superiority of the proposed method is fully demonstrated by comparing it with existing baseline methods. Full article
(This article belongs to the Special Issue Advances in Multi-Media Network Transmission)
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35 pages, 4329 KiB  
Article
Hybridizing of Whale and Moth-Flame Optimization Algorithms to Solve Diverse Scales of Optimal Power Flow Problem
by Mohammad H. Nadimi-Shahraki, Ali Fatahi, Hoda Zamani, Seyedali Mirjalili and Diego Oliva
Electronics 2022, 11(5), 831; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050831 - 07 Mar 2022
Cited by 38 | Viewed by 2507
Abstract
The optimal power flow (OPF) is a practical problem in a power system with complex characteristics such as a large number of control parameters and also multi-modal and non-convex objective functions with inequality and nonlinear constraints. Thus, tackling the OPF problem is becoming [...] Read more.
The optimal power flow (OPF) is a practical problem in a power system with complex characteristics such as a large number of control parameters and also multi-modal and non-convex objective functions with inequality and nonlinear constraints. Thus, tackling the OPF problem is becoming a major priority for power engineers and researchers. Many metaheuristic algorithms with different search strategies have been developed to solve the OPF problem. Although, the majority of them suffer from stagnation, premature convergence, and local optima trapping during the optimization process, which results in producing low solution qualities, especially for real-world problems. This study is devoted to proposing an effective hybridizing of whale optimization algorithm (WOA) and a modified moth-flame optimization algorithm (MFO) named WMFO to solve the OPF problem. In the proposed WMFO, the WOA and the modified MFO cooperate to effectively discover the promising areas and provide high-quality solutions. A randomized boundary handling is used to return the solutions that have violated the permissible boundaries of search space. Moreover, a greedy selection operator is defined to assess the acceptance criteria of new solutions. Ultimately, the performance of the WMFO is scrutinized on single and multi-objective cases of different OPF problems including standard IEEE 14-bus, IEEE 30-bus, IEEE 39-bus, IEEE 57-bus, and IEEE118-bus test systems. The obtained results corroborate that the proposed algorithm outperforms the contender algorithms for solving the OPF problem. Full article
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20 pages, 3700 KiB  
Article
Reputation-Based Sharding Consensus Model in Information-Centric Networking
by Jia Shi, Xuewen Zeng and Yang Li
Electronics 2022, 11(5), 830; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050830 - 07 Mar 2022
Cited by 1 | Viewed by 1824
Abstract
The various integration systems of blockchain and information-centric network (ICN) have been applied to provide a trusted and neutral approach to cope with large-scale content distribution in IoT, AR/VR, or 5G/6G scenarios. As a result, the scalability problem of blockchain has been an [...] Read more.
The various integration systems of blockchain and information-centric network (ICN) have been applied to provide a trusted and neutral approach to cope with large-scale content distribution in IoT, AR/VR, or 5G/6G scenarios. As a result, the scalability problem of blockchain has been an increasing concern for researchers. The sharding mechanism is recognized as a promising approach to address this challenge. However, there are still many problems in the existing schemes. Firstly, real-time processing speed trades off security of validation. Secondly, simply randomly assigning nodes to the shards may make nodes located very far from each other, which increases the block propagation time and reduces the efficiency advantage brought by the sharding mechanism. Therefore, we optimize a reputation-based sharding consensus model by multi-dimension trust and leverage the affinity propagation (AP) algorithm for gathering consensus nodes into shards. Given the minimal possibility to be at fault in the security of validation, clients can achieve real-time processing speed with assurance. The evaluation results show that the normalized mean square error (NMSE) between the estimated reputation value and the real reputation value of our reputation scheme is less than 0.02. Meanwhile, compared with the classical sharding scheme Omniledger, TPS performance can achieve 1.4 times promotion in the case of a large-scale blockchain network of 1000 nodes. Full article
(This article belongs to the Special Issue Feature Papers in "Networks" Section)
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19 pages, 5971 KiB  
Article
A Novel Single-Stage Common-Ground Transformerless Buck–Boost Inverter
by Dai-Van Vo, Minh-Khai Nguyen, Truong-Duy Duong, Tan-Tai Tran, Young-Cheol Lim and Joon-Ho Choi
Electronics 2022, 11(5), 829; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050829 - 07 Mar 2022
Cited by 8 | Viewed by 2331
Abstract
In this article, a novel single-stage transformerless buck–boost inverter is introduced. The proposed inverter can share a common ground between the DC input side and the grid; this leads to having a zero-leakage current. The proposed inverter also provides the buck and boost [...] Read more.
In this article, a novel single-stage transformerless buck–boost inverter is introduced. The proposed inverter can share a common ground between the DC input side and the grid; this leads to having a zero-leakage current. The proposed inverter also provides the buck and boost voltage capabilities. Additionally, the power switches are operated at high frequency in the half-cycle of the sinusoidal wave, so the efficiency of the proposed inverter can be improved. Operating analysis, design consideration, comparison, and simulation study are presented. Finally, a 500 W laboratory prototype is also built to confirm the correctness and feasibility of the proposed inverter. Full article
(This article belongs to the Special Issue Innovative Technologies in Power Converters)
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20 pages, 758 KiB  
Article
Modeling and Performance Analysis in UAV-Assisted Cellular Networks with Clustered Edge Users
by Yuanyuan Yao, Yunga Wu, Zhengyu Zhu, Xiaoqi Qin and Xinwei Yue
Electronics 2022, 11(5), 828; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050828 - 07 Mar 2022
Cited by 2 | Viewed by 3238
Abstract
A UAV-assisted cellular network can provide ubiquitous links to everything and it is considered to be one of the key technologies for 6G wireless networks. In this paper, we consider an uplink wireless network with a macrobase station (MBS) and cellular users. However, [...] Read more.
A UAV-assisted cellular network can provide ubiquitous links to everything and it is considered to be one of the key technologies for 6G wireless networks. In this paper, we consider an uplink wireless network with a macrobase station (MBS) and cellular users. However, the coverage equality of edge users cannot be guaranteed in scenarios where data service is dense. Specifically, a novel topology of the UAV-assisted wireless network is considered. UAVs are deployed upon the cell edge to serve edge users with poor communication quality. To avoid larger interference caused by users and UAVs in the overlapping area, the locations of these UAVs are modeled as a homogeneous Poisson point process (HPPP) under the Poisson cluster distance constraint (PCDC). In addition, we assume that edge users cluster around each UAV and model their locations as Poisson cluster processes (PCPs). Initially, the Laplace transforms of intra-cluster interference, inter-cluster interference, and other interference are derived. Subsequently, coverage probability and area spectrum efficiency are derived for UAVs and MBS using tools from stochastic geometry. Moreover, the energy efficiency of the system is obtained. Simulation results are examined to validate the accuracy of theoretical analysis and provide insights into the effects of the system parameters as well as useful guidelines for practical system design. Full article
(This article belongs to the Special Issue Unmanned Aerial Vehicle (UAV) Communication and Networking)
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29 pages, 13532 KiB  
Article
Employing a Wireless Sensing Network for AIoT Based on a 5G Approach
by Sung-Jung Hsiao
Electronics 2022, 11(5), 827; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050827 - 07 Mar 2022
Cited by 3 | Viewed by 4669
Abstract
In this paper, wireless sensing networks are considered in the context of the 5G communication architecture in order to ensure the transmission efficiency of the sensed data transmitted by the system. The various types of environmental sensors are very diverse. Wireless sensing networks [...] Read more.
In this paper, wireless sensing networks are considered in the context of the 5G communication architecture in order to ensure the transmission efficiency of the sensed data transmitted by the system. The various types of environmental sensors are very diverse. Wireless sensing networks may include many different types of sensing devices or data related to images or pattern transmission, among others, and are often limited by the problem of insufficient network bandwidth. By using 5G communications for data transmission, the problem of limited network bandwidth can be solved. In addition to the use of 5G transmission, when the NB-IoT method is used within the 5G network environment, it is much more efficient than that under the original LTE network conditions. Therefore, using 5G to transmit data provides the advantages of high transmission efficiency and data integrity. In this paper, in addition to analyzing the development of 5G technology, the proposed approach uses MATLAB software to simulate the generation of 5G signals under various parameter settings representing a range of conditions. Finally, our approach discusses the use of a 5G communication module, including driver installation and data transmission testing. At present, the 5G network architecture is still under construction worldwide. According to the transmission speed test data obtained in this study, the transmission efficiency of 5G is better than that of precursor generations. Full article
(This article belongs to the Special Issue Wireless Sensor Networks Applications in Internet of Things)
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13 pages, 4363 KiB  
Article
Performance Investigation of Power Inverter Components Submersed in Subcooled Liquid Nitrogen for Electric Aircraft
by M. S. Hassan, Tanemasa Asano, Masahito Shoyama and Gamal M. Dousoky
Electronics 2022, 11(5), 826; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050826 - 07 Mar 2022
Cited by 1 | Viewed by 2000
Abstract
Investigating the performance of power electronics devices and thus power inverters at cryogenic temperatures for electric aircraft systems are of great interest. Accordingly, the purpose of this study is to examine the inverter circuit technologies used in cryogenically-cooled electric aircraft applications from three [...] Read more.
Investigating the performance of power electronics devices and thus power inverters at cryogenic temperatures for electric aircraft systems are of great interest. Accordingly, the purpose of this study is to examine the inverter circuit technologies used in cryogenically-cooled electric aircraft applications from three perspectives: inverter topologies, power capabilities, and electromagnetic interference (EMI) that may occur. At a cryogenic temperature, the characteristics of five power semiconductor switches with different technologies (Si MOS, SiC MOS, and GaN HEMT) used in cryogenically-cooled electric aircraft inverters were tested and the results were presented. Furthermore, the low-temperature performance of three types of capacitors commonly used in power electronics inverters was investigated. The research findings provide crucial considerations for the research and development of power inverters cooled by sub-cooled liquid nitrogen for modern electric aircraft. Full article
(This article belongs to the Section Industrial Electronics)
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14 pages, 7013 KiB  
Article
A 130-to-220-GHz Frequency Quadrupler with 80 dB Dynamic Range for 6G Communication in 0.13-μm SiGe Process
by Tianxiang Wu, Zhiyuan Cao, Zhuofan Xu, Liuyao Dai, Wei Mao, Jin He, Shunli Ma and Hao Yu
Electronics 2022, 11(5), 825; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050825 - 07 Mar 2022
Viewed by 2096
Abstract
This paper presents a broadband frequency quadrupler (FQ) implemented with a standard 130-nm SiGe BiCMOS process. Two broadband push-push frequency doublers (×2) operate at an input frequency of 32.5–55 GHz and 65–110 GHz, respectively. To properly drive the two doublers with enough input [...] Read more.
This paper presents a broadband frequency quadrupler (FQ) implemented with a standard 130-nm SiGe BiCMOS process. Two broadband push-push frequency doublers (×2) operate at an input frequency of 32.5–55 GHz and 65–110 GHz, respectively. To properly drive the two doublers with enough input power and bandwidth, two transformer coupled power amplifiers (PAs) have been adopted. The former power amplifier is based on a neutralized capacitor structure and the latter is based on a transformer topology. A nonlinear device model and a systematic methodology to generate maximum power at second harmonic are proposed. By manipulating the device nonlinearity and optimizing the magnetically and capacitively coupled resonator (MCCR) matching networks, optimum conditions for harmonic power generation are provided. The measurement results show that the proposed quadrupler provides a 90-GHz bandwidth with an 80-dB dynamic range and a high energy efficiency η of 3.7% at 210 GHz. Full article
(This article belongs to the Special Issue Feature Papers in "Networks" Section)
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20 pages, 11518 KiB  
Article
Design and Analysis of Anti-Noise Parameter-Variable Zeroing Neural Network for Dynamic Complex Matrix Inversion and Manipulator Trajectory Tracking
by Peng Zhou, Mingtao Tan, Jianbo Ji and Jie Jin
Electronics 2022, 11(5), 824; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050824 - 07 Mar 2022
Cited by 6 | Viewed by 1626
Abstract
Dynamic complex matrix inversion (DCMI) problems frequently arise in the territories of mathematics and engineering, and various recurrent neural network (RNN) models have been reported to effectively find the solutions of the DCMI problems. However, most of the reported works concentrated on solving [...] Read more.
Dynamic complex matrix inversion (DCMI) problems frequently arise in the territories of mathematics and engineering, and various recurrent neural network (RNN) models have been reported to effectively find the solutions of the DCMI problems. However, most of the reported works concentrated on solving DCMI problems in ideal no noise environment, and the inevitable noises in reality are not considered. To enhance the robustness of the existing models, an anti-noise parameter-variable zeroing neural network (ANPVZNN) is proposed by introducing a novel activation function (NAF). Both of mathematical analysis and numerical simulation results demonstrate that the proposed ANPVZNN model possesses fixed-time convergence and robustness for solving DCMI problems. Besides, a successful ANPVZNN-based manipulator trajectory tracking example further verifies its robustness and effectiveness in practical applications. Full article
(This article belongs to the Special Issue Analog AI Circuits and Systems)
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19 pages, 1236 KiB  
Article
Coprime Transformed Nested Array with Enhanced DOFs and Reduced Mutual Coupling Based on the Difference and Sum Coarray
by Junchi Ma, Shunan Zhong, Zhe Peng, Wei Gao, Weijiang Wang and Xiaohua Wang
Electronics 2022, 11(5), 823; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050823 - 06 Mar 2022
Cited by 1 | Viewed by 1290
Abstract
Recently, the concept of the difference and sum coarray has attracted increasing interest in the direction of the arrival estimation field because it can generate enhanced degrees of freedom. In this paper, we propose an improved transformed nested array design strategy by relaxing [...] Read more.
Recently, the concept of the difference and sum coarray has attracted increasing interest in the direction of the arrival estimation field because it can generate enhanced degrees of freedom. In this paper, we propose an improved transformed nested array design strategy by relaxing the constraints on the dense subarray of the transformed nested array. Then, three conditions are given for the array design to ensure the continuity of the difference and sum coarray. Based on the strategy, we develop a novel nested configuration named coprime transformed nested array (CTNA) whose dense subarray is a coprime structure, and the closed-form expressions for the sensor positions and the range of consecutive coarray are derived. CTNA can increase the number of degrees of freedom (DOFs) compared to the existing nested arrays, while the mutual coupling effect can be maintained at the same low level as the coprime arrays, which indicates that CTNA has the merits of both nested array and coprime array. Numerical simulations are performed to verify the superiority of the proposed array configuration in terms of the number of DOFs, mutual coupling and direction of arrival (DOA) estimation accuracy. Full article
(This article belongs to the Section Circuit and Signal Processing)
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17 pages, 8314 KiB  
Article
Transient Modulation for the Step-Load-Change Process in a Dual-Bridge Series Resonant Converter
by Hui Xu, Shengzhi Zhou, Xiaodong Li, Hao Chen and Song Hu
Electronics 2022, 11(5), 822; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050822 - 06 Mar 2022
Cited by 1 | Viewed by 1605
Abstract
A phase-shifted dual-bridge series resonant DC-DC converter (DBSRC) is a competitive candidate for applications of an energy storage system. At the request of a step-load-change command such as the start-up and power-level change, the converter may suffer from large-amplitude transient oscillations due to [...] Read more.
A phase-shifted dual-bridge series resonant DC-DC converter (DBSRC) is a competitive candidate for applications of an energy storage system. At the request of a step-load-change command such as the start-up and power-level change, the converter may suffer from large-amplitude transient oscillations due to improper transient modulation. Furthermore, the DC bias current and overshoot current/voltage in the resonant tank and transformer caused by oscillations may result in transformer saturation and poor dynamic performance. To solve these problems, two fast transient modulation (FTM) methods are proposed in this paper. First, based on the steady-state analysis of the converter with phase-shift control, the current and voltage trajectory of the resonant capacitor can be obtained. Then, the detailed principles of two FTM methods are explained for achieving a smooth transition. Through the adjustment of the durations of the adjacent switching intervals temporarily, the transient trajectory can be predicted and is expected to match the destination trajectory within one switching period. Consequently, the proposed FTM methods enable the converter to move from one steady state to another instantly and the step-load-change transition can be an overshoot-free procedure. Finally, both simulation and experimental tests prove that the two modulation methods can effectively eliminate DC bias current and overshoot current/voltage in the DBSRC transient process and obtain a fast transient response. Full article
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19 pages, 8998 KiB  
Article
A Novel Meander Bowtie-Shaped Antenna with Multi-Resonant and Rejection Bands for Modern 5G Communications
by Yanal S. Faouri, Sarosh Ahmad, Naser Ojaroudi Parchin, Chan Hwang See and Raed Abd-Alhameed
Electronics 2022, 11(5), 821; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050821 - 06 Mar 2022
Cited by 32 | Viewed by 2621
Abstract
To support various fifth generation (5G) wireless applications, a small, printed bowtie-shaped microstrip antenna with meandered arms is reported in this article. Because it spans the broad legal range, the developed antenna can serve or reject a variety of applications such as wireless [...] Read more.
To support various fifth generation (5G) wireless applications, a small, printed bowtie-shaped microstrip antenna with meandered arms is reported in this article. Because it spans the broad legal range, the developed antenna can serve or reject a variety of applications such as wireless fidelity (Wi-Fi), sub-6 GHz, and ultra-wideband (UWB) 5G communications due to its multiband characterization and optimized rejection bands. The antenna is built on an FR-4 substrate and powered via a 50-Ω microstrip feed line linked to the right bowtie’s side. The bowtie’s left side is coupled via a shorting pin to a partial ground at the antenna’s back side. A gradually increasing meandering microstrip line is connected to both sides of the bowtie to enhance the rejection and operating bands. The designed antenna has seven operating frequency bands of (2.43–3.03) GHz, (3.71–4.23) GHz, (4.76–5.38) GHz, (5.83–6.54) GHz, (6.85–7.44) GHz, (7.56–8.01) GHz, and (9.27–13.88) GHz. The simulated scattering parameter S11 reveals six rejection bands with percentage bandwidths of 33.87%, 15.73%, 11.71, 7.63%, 6.99%, and 12.22%, respectively. The maximum gain of the proposed antenna is 4.46 dB. The suggested antenna has been built, and the simulation and measurement results are very similar. The reported antenna is expanded to a four-element design to investigate its MIMO characteristics. Full article
(This article belongs to the Special Issue Antenna Designs for 5G/IoT and Space Applications)
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23 pages, 2754 KiB  
Review
A Comprehensive Review of Channel Modeling for Land Mobile Satellite Communications
by Mauro Tropea and Floriano De Rango
Electronics 2022, 11(5), 820; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050820 - 06 Mar 2022
Cited by 11 | Viewed by 4363
Abstract
As demands on the network continue to grow, it is increasingly important to upgrade the existing infrastructure in order to offer higher bandwidth and service level guarantees to users. Next generation networks (NGNs) represent a fully IP-based architecture that is able to support [...] Read more.
As demands on the network continue to grow, it is increasingly important to upgrade the existing infrastructure in order to offer higher bandwidth and service level guarantees to users. Next generation networks (NGNs) represent a fully IP-based architecture that is able to support different technologies. In this context, the satellite networks are considered a fundamental part for future hybrid architectures. In this scenario, knowing satellite channel propagation characteristics in order to be able to design a communication system to respond to new user needs is of fundamental importance. Many papers in the literature show channel models in different satellite scenarios both for fixed and mobile applications; however, to the best of our knowledge, nobody presents an overview on different satellite models based on Markov chains. This paper wants to present a comprehensive review of the most recent developments in satellite channel communications related to mobile services and, in particular, for the land mobile satellite systems. The work presents all different types of Markov models, from single-state to multi-state models, that have been proposed in the literature from the early 1980s. Full article
(This article belongs to the Special Issue State-of-the-Art in Satellite Communication Networks)
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16 pages, 2359 KiB  
Article
Finite-Time Parameter Observer-Based Sliding Mode Control for a DC/DC Boost Converter with Constant Power Loads
by Wei He and Yukai Shang
Electronics 2022, 11(5), 819; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050819 - 05 Mar 2022
Cited by 7 | Viewed by 1767
Abstract
Constant power loads have negative impedance characteristics, which reduce the damping of DC/DC converter systems and have negative effects on the stability of the DC microgrid. In this paper, a finite-time parameter observer-based sliding mode controller is proposed for a boost converter with [...] Read more.
Constant power loads have negative impedance characteristics, which reduce the damping of DC/DC converter systems and have negative effects on the stability of the DC microgrid. In this paper, a finite-time parameter observer-based sliding mode controller is proposed for a boost converter with constant power loads. Firstly, a non-singular terminal sliding-mode controller is designed based on the flatness of the differential and sliding mode control theory. Secondly, a finite-time observer is designed to estimate the input voltage and tunes the parameter of the controller in time. Thirdly, the finite-time stability of the closed-loop system is proved through the proposed controller. Finally, the effectiveness and robustness of the proposed controller with unknown input voltage are verified by simulation. The proposed controller can guarantee finite-time convergence without input voltage sensors, which can reduce system cost and improve system reliability. Full article
(This article belongs to the Special Issue Power Electronics Converter Topologies and Control Techniques)
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15 pages, 1057 KiB  
Article
Water Is a Viable Data Storage Medium: A Security and Privacy Viewpoint
by Shahzaib Tahir, Hasan Tahir, Ruhma Tahir, Muttukrishnan Rajarajan and Haider Abbas
Electronics 2022, 11(5), 818; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050818 - 05 Mar 2022
Viewed by 6614
Abstract
The security of IoT devices is a major concern that needs to be addressed for their wide adoption. Users are constantly seeking devices that are faster and capable of holding large amounts of data securely. It is purported that water has memory of [...] Read more.
The security of IoT devices is a major concern that needs to be addressed for their wide adoption. Users are constantly seeking devices that are faster and capable of holding large amounts of data securely. It is purported that water has memory of its own and the ability to retain memory of the substances that are dissolved into it, even after being substantially and serially diluted. It was also observed in the lab setting that the microscopic pattern of water obtained from the same vessel by different people is unique but can easily distinguish those individuals if the same experiment is executed repeatedly. Furthermore, extensive research is already underway that explores the storage of data on water and liquids. This leads to the requirement of taking the security and privacy concerns related to the storage of data on water into consideration, especially when the real-time collection of data related to water through the IoT devices is of interest. Otherwise, the water memory aspect may lead to leakage of the data and, consequently, the data owners identity. Therefore, this article for the first time highlights the security and privacy implications related to water memory and discusses the possible countermeasures to effectively handle these potential threats. This article also presents a framework to securely store sensitive data on water. The proof-of-concept prototype is implemented and tested over a real-world dataset to analyze the feasibility of the proposed framework. The performance analysis yields that the proposed framework can be deployed once data storage on water is widely used. Full article
(This article belongs to the Special Issue Security and Privacy in Blockchain/IoT)
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4 pages, 173 KiB  
Editorial
High-Frequency Vacuum Electron Devices
by Jinjun Feng, Yubin Gong, Chaohai Du and Adrian Cross
Electronics 2022, 11(5), 817; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050817 - 05 Mar 2022
Cited by 2 | Viewed by 2070
Abstract
Vacuum electron devices at frequencies of millimeter waves and terahertz play highly important roles in the modern high-data rate and broadband communication system, high-resolution detection and imaging, medical diagnostics, magnetically confined nuclear fusion, etc [...] Full article
(This article belongs to the Special Issue High-Frequency Vacuum Electron Devices)
14 pages, 598 KiB  
Article
Fast Design Space Exploration and Multi-Objective Optimization of Wide-Band Noise-Canceling LNAs
by Karim Elmeligy and Hesham Omran
Electronics 2022, 11(5), 816; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050816 - 05 Mar 2022
Cited by 6 | Viewed by 3199
Abstract
Design optimization of RF low-noise amplifiers (LNAs) remains a time-consuming and complex process. Iterations are needed to adjust impedance matching, gain, and noise figure (NF) simultaneously. The process can involve more iterations to adjust the non-linear behavior of the circuit which can be [...] Read more.
Design optimization of RF low-noise amplifiers (LNAs) remains a time-consuming and complex process. Iterations are needed to adjust impedance matching, gain, and noise figure (NF) simultaneously. The process can involve more iterations to adjust the non-linear behavior of the circuit which can be represented by the input-referred third-order intercept (IIP3). In this work, we present a variation-aware automated design and optimization flow for a wide-band noise-canceling LNA. We include the circuit non-linearity in the optimization flow without using a simulator in the loop. By describing the transistors using precomputed lookup tables (LUTs), a design database that contains 200,000 design points is generated in 3 s only without non-linearity computation and 10 s when non-linearity is taken into account. Using a gm/ID-based correct-by-construction design procedure, the generated design points automatically satisfy proper biasing, input matching, and gain matching requirements. The generated database enables the designer to visualize the design space and explore the design trade-offs. Moreover, multi-objective optimization across corners for a given set of specifications is applied to find the Pareto-optimal fronts of the design figures-of-merit. We demonstrate the presented flow using two design examples in a 65 nm process and the results are verified using Cadence Spectre. Full article
(This article belongs to the Special Issue Feature Papers in Circuit and Signal Processing)
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27 pages, 11649 KiB  
Article
Renewable Energy Micro-Grid Interfacing: Economic and Environmental Issues
by Adel A. Abou El-Ela, Ragab A. El-Sehiemy, Sohir M. Allam, Abdullah M. Shaheen, Nadia A. Nagem and Adel M. Sharaf
Electronics 2022, 11(5), 815; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050815 - 05 Mar 2022
Cited by 21 | Viewed by 2052
Abstract
This paper presents a study on the technical, economic, and environmental aspects of renewable energy resources-based distributed generation units (DGs). These units are connected to the medium-voltage network to create a new structure called a microgrid (MG). Renewable energies, especially wind and solar, [...] Read more.
This paper presents a study on the technical, economic, and environmental aspects of renewable energy resources-based distributed generation units (DGs). These units are connected to the medium-voltage network to create a new structure called a microgrid (MG). Renewable energies, especially wind and solar, are the most important generation units among DGs. The stochastic behavior of renewable resources increases the need to find the optimum operation of the MG. The optimal operation of a typical MG aims to simultaneously minimize the operational costs and the accompanied emission pollutants over a daily scheduling horizon. Several renewable DGs are investigated in the MG, consisting of biomass generators (BGs), wind turbines (WTs), and photovoltaics (PV). For the proposed operating strategy of the MG, a recent equilibrium optimization (EO) technique is developed and is inspired by the mass balance models for a control volume that are used to estimate their dynamic and equilibrium states. The uncertainties of wind speed and solar irradiation are considered via the Weibull and Beta-probability density functions (PDF) with different states of mean and standard deviation for each hour, respectively. Based on the developed EO, the hourly output powers of the PV, WT, and BGs are optimized, as are the associated power factors of the BGs. The proposed MG operating strategy based on the developed EO is tested on the IEEE 33-bus system and the practical large-scale 141-bus system of AES-Venezuela in the metropolitan area of Caracas. The simulation results demonstrate the significant benefits of the optimal operation of a typical MG using the developed EO by minimizing the operational costs and emissions while preserving the penetration level of the DGs by 60%. Additionally, the voltage profile of the MG operation for each hour is highly enhanced where the minimum voltage at each hour is corrected within the permissible limit of [0.95–1.05] Pu. Moreover, the active power losses per hour are greatly reduced. Full article
(This article belongs to the Special Issue Energy Harvesting and Energy Storage Systems)
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16 pages, 3754 KiB  
Article
Robust Terminal Sliding Mode Control on SE(3) for Gough–Stewart Flight Simulator Motion Platform with Payload Uncertainty
by Binhai Xie and Shuling Dai
Electronics 2022, 11(5), 814; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050814 - 04 Mar 2022
Cited by 4 | Viewed by 1846
Abstract
This work proposes a robust terminal sliding mode control scheme on Lie group space SE(3) for Gough–Stewart flight simulator motion systems with payload uncertainty. A complete dynamic model with geometric mechanical structures and a computer dynamic model built in the MATLAB/Simulink package are [...] Read more.
This work proposes a robust terminal sliding mode control scheme on Lie group space SE(3) for Gough–Stewart flight simulator motion systems with payload uncertainty. A complete dynamic model with geometric mechanical structures and a computer dynamic model built in the MATLAB/Simulink package are briefly presented. The robust control strategy on the Lie group SE(3) is applied at the workspace level to counteract the effects of imperfect compensation due to model simplification and payload uncertainty in flight simulator application. With exponential coordinates for configuration error and adjoint operator on Lie algebra se(3), the robust control strategy is designed to guarantee almost global finite-time convergence over state space through the Lyapunov stability theory. Finally, a describing function and a step acceleration response to characterize the performance of a flight simulator motion base are employed to compare the robustness performance of the proposed controller on SE(3) with the conventional terminal sliding mode controller on Cartesian space. The comparison experimental results verify that the proposed controller on SE(3) provides better robustness than the conventional controller on Cartesian space, which means higher bandwidth in two degrees of freedom and faster response with smaller tracking error in six degrees of freedom. Full article
(This article belongs to the Special Issue Nonlinear Control in Robotics)
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12 pages, 531 KiB  
Article
‘Should I Turn on My Video Camera?’ The Students’ Perceptions of the use of Video Cameras in Synchronous Distant Learning
by Živilė Sederevičiūtė-Pačiauskienė, Ilona Valantinaitė and Vaida Asakavičiūtė
Electronics 2022, 11(5), 813; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050813 - 04 Mar 2022
Cited by 17 | Viewed by 3384
Abstract
One of the challenges teachers and students face in online synchronous learning is not turning on their video cameras. The reasons are multitasking, being concerned about the background, psychological barriers, and poor internet connection. In this study, social presence theory (SPT) was employed [...] Read more.
One of the challenges teachers and students face in online synchronous learning is not turning on their video cameras. The reasons are multitasking, being concerned about the background, psychological barriers, and poor internet connection. In this study, social presence theory (SPT) was employed as the theoretical lens to understand the possible impacts of video cameras in synchronous online learning. Social presence allows individuals to make personal characteristics visible to the community. Students experience greater levels of trust and rapport because of verbal and nonverbal cues that occur when video cameras are turned on in video conferencing. The use of video cameras in synchronous distant learning creates intimacy and immediacy, leading to teacher–learner social presence, which leads to dialog. The phenomenographic study was carried out to analyze the students’ perceptions of the phenomena. The eighty-two first-year undergraduate and doctoral students took part in the study. It showed that students perceive a video camera as a tool for cooperation, as well as for self-discipline and self-control. The students relate the use of video cameras with quality studies, the ability to interact, and to be a part of the process. They feel less inclined to participate when their cameras are off. That leads to the weaker student–teacher relationship, which is achieved with a higher social presence. It is essential to see one other to strengthen students’ motivation, sense of belonging, and community in the courses for first-year students who are still developing learning habits and social networks. Full article
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17 pages, 12551 KiB  
Article
Incorporation of Synthetic Data Generation Techniques within a Controlled Data Processing Workflow in the Health and Wellbeing Domain
by Mikel Hernandez, Gorka Epelde, Andoni Beristain, Roberto Álvarez, Cristina Molina, Xabat Larrea, Ane Alberdi, Michalis Timoleon, Panagiotis Bamidis and Evdokimos Konstantinidis
Electronics 2022, 11(5), 812; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050812 - 04 Mar 2022
Cited by 14 | Viewed by 9190
Abstract
To date, the use of synthetic data generation techniques in the health and wellbeing domain has been mainly limited to research activities. Although several open source and commercial packages have been released, they have been oriented to generating synthetic data as a standalone [...] Read more.
To date, the use of synthetic data generation techniques in the health and wellbeing domain has been mainly limited to research activities. Although several open source and commercial packages have been released, they have been oriented to generating synthetic data as a standalone data preparation process and not integrated into a broader analysis or experiment testing workflow. In this context, the VITALISE project is working to harmonize Living Lab research and data capture protocols and to provide controlled processing access to captured data to industrial and scientific communities. In this paper, we present the initial design and implementation of our synthetic data generation approach in the context of VITALISE Living Lab controlled data processing workflow, together with identified challenges and future developments. By uploading data captured from Living Labs, generating synthetic data from them, developing analysis locally with synthetic data, and then executing them remotely with real data, the utility of the proposed workflow has been validated. Results have shown that the presented workflow helps accelerate research on artificial intelligence, ensuring compliance with data protection laws. The presented approach has demonstrated how the adoption of state-of-the-art synthetic data generation techniques can be applied for real-world applications. Full article
(This article belongs to the Special Issue Recent Advances in Synthetic Data Generation)
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12 pages, 2975 KiB  
Article
Theory of Peer-to-Peer Locking of High-Power Gyrotron Oscillators Coupled with Delay
by Asel B. Adilova and Nikita M. Ryskin
Electronics 2022, 11(5), 811; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050811 - 04 Mar 2022
Cited by 2 | Viewed by 1172
Abstract
Peer-to-peer locking is a promising way to combine the power of high-power microwave oscillators. The peer-to-peer locking of gyrotrons is especially important because arrays of coupled gyrotrons are of special interest for fusion and certain other applications. However, in case of coupled microwave [...] Read more.
Peer-to-peer locking is a promising way to combine the power of high-power microwave oscillators. The peer-to-peer locking of gyrotrons is especially important because arrays of coupled gyrotrons are of special interest for fusion and certain other applications. However, in case of coupled microwave oscillators, the effect of delay in coupling is very significant and should be taken into account. In this article, we present the model of two delay-coupled gyrotrons. We develop an approximate theory of phase locking based on the generalized Adler’s equation, which allows for the treatment of in-phase and anti-phase locking modes. We also present a more rigorous bifurcation analysis of phase locking by using XPPAUT software under the limitation of small delay time. The structure of the phase-locking domains on the frequency-mismatch–coupling-strength plane of parameters is examined. Finally, we verify the results by numerical simulations in the case of finite delay time. The simulations reveal various regimes, including peer-to-peer locking, the suppression of one gyrotron by another, as well as the excitation of one gyrotron by another. Full article
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22 pages, 805 KiB  
Article
Robust Latent Common Subspace Learning for Transferable Feature Representation
by Shanhua Zhan, Weijun Sun and Peipei Kang
Electronics 2022, 11(5), 810; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050810 - 04 Mar 2022
Cited by 4 | Viewed by 1257
Abstract
This paper proposes a novel robust latent common subspace learning (RLCSL) method by integrating low-rank and sparse constraints into a joint learning framework. Specifically, we transform the data from source and target domains into a latent common subspace to perform the data reconstruction, [...] Read more.
This paper proposes a novel robust latent common subspace learning (RLCSL) method by integrating low-rank and sparse constraints into a joint learning framework. Specifically, we transform the data from source and target domains into a latent common subspace to perform the data reconstruction, i.e., the transformed source data is used to reconstruct the transformed target data. We impose joint low-rank and sparse constraints on the reconstruction coefficient matrix which can achieve following objectives: (1) the data from different domains can be interlaced by using the low-rank constraint; (2) the data from different domains but with the same label can be aligned together by using the sparse constraint. In this way, the new feature representation in the latent common subspace is discriminative and transferable. To learn a suitable classifier, we also integrate the classifier learning and feature representation learning into a unified objective and thus the high-level semantics label (data label) is fully used to guide the learning process of these two tasks. Experiments are conducted on diverse data sets for image, object, and document classifications, and encouraging experimental results show that the proposed method outperforms some state-of-the-arts methods. Full article
(This article belongs to the Special Issue Recent Advances in Representation Learning)
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22 pages, 605 KiB  
Article
Automatic and Interactive Program Parallelization Using the Cetus Source to Source Compiler Infrastructure v2.0
by Akshay Bhosale, Parinaz Barakhshan, Miguel Romero Rosas and Rudolf Eigenmann
Electronics 2022, 11(5), 809; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050809 - 04 Mar 2022
Cited by 4 | Viewed by 2217
Abstract
This paper presents an overview and evaluation of the existing and newly added analysis and transformation techniques in the Cetus source-to-source compiler infrastructure. Cetus is used for research on compiler optimizations for multi-cores with an emphasis on automatic parallelization. The compiler has gone [...] Read more.
This paper presents an overview and evaluation of the existing and newly added analysis and transformation techniques in the Cetus source-to-source compiler infrastructure. Cetus is used for research on compiler optimizations for multi-cores with an emphasis on automatic parallelization. The compiler has gone through several iterations of benchmark studies and implementations of those techniques that could improve the parallel performance of these programs. This work seeks to measure the impact of the existing Cetus techniques on the newer versions of some of these benchmarks. In addition, we describe and evaluate the recent advances made in Cetus, which are the capability of analyzing subscripted subscripts and a feature for interactive parallelization. Cetus started as a class project in the 1990s and grew with support from Purdue University and from the National Science Foundation (NSF), as well as through countless volunteer projects by enthusiastic students. While many Version-1 releases were distributed via the Purdue download site, Version 2 is being readied for release from the University of Delaware. Full article
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20 pages, 5097 KiB  
Article
A Simple Commutation Method and a Cost-Effective Clamping Circuit for Three-to-Five-Phase Indirect-Matrix Converters
by Kotb B. Tawfiq, Mohamed N. Ibrahim and Peter Sergeant
Electronics 2022, 11(5), 808; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050808 - 04 Mar 2022
Cited by 3 | Viewed by 1884
Abstract
This article presents and analyzes a three-to-five-phase indirect matrix converter (IMC) structure for directly supplying a five-phase static RL load from a three-phase supply. The IMC topology offers a lower number of switches, a simple commutation procedure and a cost-effective clamping [...] Read more.
This article presents and analyzes a three-to-five-phase indirect matrix converter (IMC) structure for directly supplying a five-phase static RL load from a three-phase supply. The IMC topology offers a lower number of switches, a simple commutation procedure and a cost-effective clamping circuit in comparison to the direct matrix converter (DMC). A simple clamping circuit with one ultrafast diode and one small capacitor is proposed to protect the switches of the IMC from overvoltage. The issues of powering up the IMC with the simple clamping circuit is discussed in detail. The instructions for the safe start-up of the IMC with the proposed clamping circuit is introduced based on the simulated and the measured analyses. Moreover, a carrier-based pulse-width-modulation (CBPWM) method is also presented in order to control the switches of the IMC. The presented CBPWM method creates PWM pulses for both the inverter and the rectifier legs by using only one symmetric and triangular carrier signal. Finally, experimental and simulation testing with a five-phase R–L load demonstrate the viability and the efficiency of the introduced CBPWM algorithm for the suggested IMC. Full article
(This article belongs to the Special Issue Power Electronic Converters in a Multiphase Drive Systems)
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18 pages, 14452 KiB  
Article
A Tunable Microstrip Bandpass Filter with Two Concurrently Tuned Transmission Zeros
by Mirosław Magnuski, Dariusz Wójcik, Maciej Surma and Artur Noga
Electronics 2022, 11(5), 807; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050807 - 04 Mar 2022
Cited by 1 | Viewed by 2777
Abstract
In this paper, an electrically small tunable microstrip bandpass filter with two concurrently tuned transmission zeros (TZs) is presented. The filter consists of two coupled resonators and varactors as tuning elements. An application of a multipath coupling network results in TZs on both [...] Read more.
In this paper, an electrically small tunable microstrip bandpass filter with two concurrently tuned transmission zeros (TZs) is presented. The filter consists of two coupled resonators and varactors as tuning elements. An application of a multipath coupling network results in TZs on both sides of the passband. The filter controlled by a single voltage has a wide tuning range from 370 MHz to 800 MHz and a low insertion loss ranging from 1.9 dB to 3.4 dB. To achieve high attenuation in the stopband, two sections of the designed filter were cascaded. Both one-section and two-section filters were validated by measurements. The obtained results are in a very good agreement with simulations. Full article
(This article belongs to the Special Issue Feature Papers in Circuit and Signal Processing)
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21 pages, 10858 KiB  
Article
Dual-Band 6 × 6 MIMO Antenna System for Glasses Applications Compatible with Wi-Fi 6E and 7 Wireless Communication Standards
by Ming-An Chung and Cheng-Wei Hsiao
Electronics 2022, 11(5), 806; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050806 - 04 Mar 2022
Cited by 4 | Viewed by 2896
Abstract
Multi-user multiple-input and multiple-output (MU-MIMO) systems are the mainstream of current antenna design. This paper proposes a dual-band 6 × 6 MIMO glasses antenna for Wi-Fi 6E and Wi-Fi 7 indoor wireless communication. The six antennas have the same structure, all of which [...] Read more.
Multi-user multiple-input and multiple-output (MU-MIMO) systems are the mainstream of current antenna design. This paper proposes a dual-band 6 × 6 MIMO glasses antenna for Wi-Fi 6E and Wi-Fi 7 indoor wireless communication. The six antennas have the same structure, all of which are F-shaped monopole antennas. They are on the left and right temples, at the upper and lower ends of the left and right frames, which effectively uses the space of the glasses. The substrate uses FR4 (εr=4.4, tanδ=0.02). The antenna design is compact (9 mm × 50 mm × 0.8 mm) and the glasses model is made of FR4. The overall model is similar to virtual reality (VR) glasses, which are convenient for a user to wear. The proposed antenna has three working frequency bands, at 2.4 GHz, 5 GHz, and 6 GHz. Through matching and optimization, the reflection coefficient can be lower than −10 dB. In addition, this paper evaluates two usage environments for simulation and measurement on the head and free space. The measurement results show that when the operating frequency band is at 2.45 GHz, the antenna efficiency is 86.1%, and the antenna gain is 1.9 dB. At 5.5 GHz, the antenna efficiency is 86.5%, and the antenna gain is 4.4 dB. At 6.7 GHz, the antenna efficiency is 85.4%, and the antenna gain is 3.7 dB. When the isolation of the MIMO antenna system is optimized, the low-frequency band is better than −10 dB, and the high-frequency band is better than −20 dB. The measured envelope correlation coefficient (ECC) values are all lower than 0.1. Full article
(This article belongs to the Special Issue Antenna Design and Integration in Wireless Communications)
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17 pages, 3098 KiB  
Article
Adoption of IP Truncation in a Privacy-Based Decision Tree Pruning Design: A Case Study in Network Intrusion Detection System
by Yee Jian Chew, Shih Yin Ooi, Kok-Seng Wong, Ying Han Pang and Nicholas Lee
Electronics 2022, 11(5), 805; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics11050805 - 04 Mar 2022
Cited by 5 | Viewed by 2047
Abstract
A decision tree is a transparent model where the rules are visible and can represent the logic of classification. However, this structure might allow attackers to infer confidential information if the rules carry some sensitive information. Thus, a tree pruning methodology based on [...] Read more.
A decision tree is a transparent model where the rules are visible and can represent the logic of classification. However, this structure might allow attackers to infer confidential information if the rules carry some sensitive information. Thus, a tree pruning methodology based on an IP truncation anonymisation scheme is proposed in this paper to prune the real IP addresses. However, the possible drawback of carelessly designed tree pruning might degrade the performance of the original tree as some information is intentionally opted out for the tree’s consideration. In this work, the 6-percent-GureKDDCup’99, full-version-GureKDDCup’99, UNSW-NB15, and CIDDS-001 datasets are used to evaluate the performance of the proposed pruning method. The results are also compared to the original unpruned tree model to observe its tolerance and trade-off. The tree model adopted in this work is the C4.5 tree. The findings from our empirical results are very encouraging and spell two main advantages: the sensitive IP addresses can be “pruned” (hidden) throughout the classification process to prevent any potential user profiling, and the number of nodes in the tree is tremendously reduced to make the rule interpretation possible while maintaining the classification accuracy. Full article
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