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In terahertz (THz) wireless communication systems, non-diffraction vortex beams carrying an orbital angular momentum (OAM) have attracted extensive attention due to their ability to transmit information over long distances with high capacity. However, existing metasurfaces can only generate a single OAM mode non-diffracting vortex beam at reflection space for circular polarization (CP) incidence, limiting practical applications. To address this issue, we propose and design a polarization-frequency multiplexing transmissive THz metasurface to realize multi-mode non-diffracting vortex beams at linear polarization (LP) incidence. The meta-atom of this metasurface is composed of three anisotropic rectangular metallic structures embedded in vanadium dioxide (VO2) square rings, two circular aperture metallic grid layers, and four dielectric layers. By reasonably designing the size of the metal patch and the state of VO2, the designed metasurface can achieve polarization multiplexing and frequency multiplexing for LP incidence. Based on the phase response of the proposed meta-atoms, the transmissive metasurface can implement not only multi-mode non-diffraction vortex beams but also their space separation at two frequency ranges of 0.80–0.90 THz and 1.50–1.80 THz by changing the state of VO2. Therefore, the proposed multiple multiplexing metasurfaces can effectively shape the wavefront of non-diffraction vortex beams, which have broad application prospects in 6G THz communication. [ABSTRACT FROM AUTHOR]

With the gradual improvement of the future wireless communication technology, the demand for high information capacity and reliable links in communication systems is also ever-increasing. Programmable topological plasmonic metasurfaces, consisting of artificially engineered structures with robust propagation pathways control, have emerged as a revolutionary technology for stable microwave and on-chip communication systems. Programmable topological plasmonic metasurfaces offer unprecedented flexibility and adaptability in managing multiple communication channels as the propagation paths can be easily reconfigured to meet specific communication requirements. Here, we have experimentally demonstrated the ability to dynamically manipulate electromagnetic waves along eight distinct topological pathways for a multichannel direct communication system. The simulation results of topological plasmonic metasurfaces with different coding schemes have showcased their excellent performance in multichannel wavefront control. Experimental results have consistently aligned with the simulation findings, validating the effectiveness of multichannel topological routes. Furthermore, an eight-channel direct communication system based on a programmable topological plasmonic metasurface is designed and implemented to transmit different information. The proposed multichannel communication system based on a programmable topological plasmonic metasurface opens up new possibilities for high-capacity, efficient, and adaptive communication systems, which hold great potential in transformative applications in areas such as 6G, Internet of Things, and beyond. [ABSTRACT FROM AUTHOR]

Metasurfaces, due to their outstanding ability to control electromagnetic waves, have great application prospects in the field of wireless communication. This paper provides a comprehensive review of research work based on metasurface in three aspects: wireless power transfer, wireless information transmission, and novel wireless transceiver architectures. In the domain of wireless power transfer, several focusing metasurfaces and systems with unique performance are presented along with a new formula for calculating wireless power transfer. Concerning wireless information transmission section, the direct digital information transmission based on metasurface and the information transmission based on space-time-coding digital metasurface are introduced. Lastly, a simplified wireless transceiver with metasurfaces was introduced. The paper concludes with a discussion on the future directions of metasurfaces in the wireless communication domain. [ABSTRACT FROM AUTHOR]

The deployment of fifth-generation mobile network (5G), beyond 5G and sixth-generation mobile network platforms encounters challenges of blockage, interference, and path loss in radio mobile environments. Metasurfaces provide a promising solution to address these limitations. In this paper, we present a methodology for developing ultrathin flexible metasurface-based frequency selective surfaces (FSSs). Our approach combines thermal evaporation for metallic thin films with a macroscopic metasurface mask (something analogous to screen-printing but using thermal evaporation instead of inks). As a proof of concept, we fabricate a sub-6 GHz metasurface-based FSS using gold deposition on a flexible polyethylene terephthalate substrate. Experimental results are validated through numerical full-wave simulations using COMSOL Multiphysics and equivalent-circuit model simulations. The metasurface operates within the primary frequency band utilized in 5G networks (3–5 GHz), indicating its potential applicability across a wide range of flexible, conformal, and wearable devices. The fabricated FSS can be installed on surfaces of any shape, such as flat or curved windows, as well as on walls or other external surfaces. This methodology offers practical solutions for wireless communications and enhancing signal transmission in diverse environments. [ABSTRACT FROM AUTHOR]

Summary: In the world of emerging wireless networks, interference poses a significant challenge to reliable wireless communication. Additionally, these networks are prone to path loss and blockages, which can be addressed by utilizing the advanced technology of multihop communication with instantaneous relay (IR). However, scenarios involving IR‐assisted networks are considered instances of multihop communications that face potential obstacles caused by interference. As a result, multiple interference management approaches exist to tackle this interference issue, among which aligned interference neutralization (AIN) is a state‐of‐the‐art technology that seamlessly unifies two established interference management strategies: interference alignment (IA) and interference neutralization (IN). Therefore, this paper presents a novel tristaged AIN scheme to mitigate interference in a multicellular multiple‐input multiple‐output (MIMO) interference multiple access channel (IMAC). In the proposed scheme, the initial stage‐1 involves transmitting message signals from individual transmitters or users to the IR and the receiving base stations (BSs). In stage‐2, the IR neutralizes half of the interference signals by performing IN. Finally, in stage‐3, IA is carried out at the receiver BS terminals, aligning the remaining interference signals equally within the available dimensions. Based on this proposed approach, we determined that for an IR‐aided multicellular MIMO IMAC, the achievable degree of freedom (DoF) is 2N. The proposed approach's robustness and effectiveness have been analyzed through extensive simulations, and these simulation results indicated that the proposed approach outperforms other benchmark interference management techniques in terms of DoF and sum rate, thereby improving user performance. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach to optimize the thinning of an elliptical cylindrical array (ECA) composed of uniformly stimulated, isotropic antennas with the objective of achieving a directed beam characterized by a significantly reduced relative Sidelobe Level (SLL). The optimization process employs the Novel Particle Swarm Optimization (NPSO) method, which offers a fresh perspective on addressing electromagnetic optimization challenges by its ability to effectively explore solution spaces. By employing the NPSO algorithm, which emulates the collective behavior of swarming particles to search for optimal solutions, this study addresses complex optimization challenges inherent in antenna array design. This study focuses on identifying the optimal combination of ON–OFF components (use the minimum number of ON antenna elements) within the antenna array to produce a radiation pattern exhibiting the greatest decrease in SLL. Additionally, the First Null Beam Width (FNBW) is targeted for optimization without predefined values. The optimization approach also considers the effect of thinned array element spacing on the overall performance metrics. Out of total 36 elements, only 15 elements are switched ON and the remaining of the elements are OFF, so the total reduction or thinning of ECAA is 41.66%. Simulation results demonstrate that the proposed methodology enables a simultaneous reduction of more than half of the antenna array elements while achieving superior SLL minimization. This significant reduction in antenna elements not only contributes to simplifying the array design, but also enhances the array's beamforming capabilities. [ABSTRACT FROM AUTHOR]

The exploration of dielectric ceramics with excellent dielectric responses at Gigahertz band and Terahertz band is becoming urgent for the upcoming 6th generation wireless communication. In this work, we propose a new approach to design novel dielectric ceramics by using the density functional theory. According to the analysis of Electron Localization Functions (ELF), Density of States (DOS) and crystal bond lengths, it indicates that the strategy of co-doping with lithium and fluorine will contribute to a much more stable crystal structure of Li 0.5 NaY 9 (SiO 4) 6 O 2 F 0.5 as compared to that of NaY 9 (SiO 4) 6 O 2. Furthermore, we report the innovative synthesis of a Li 0.5 NaY 9 (SiO 4) 6 O 2 F 0.5 oxyfluoride ceramic, a solid solution with a wide sintering temperature range, along with an in-depth analysis of its crystal structure, dielectric responses at both Gigahertz band and Terahertz band, which shows the promising application of Li 0.5 NaY 9 (SiO 4) 6 O 2 F 0.5 in the 6G wireless communication. [ABSTRACT FROM AUTHOR]

Due to significant response contradictions, unidirectional carrier transmission of typical semiconductor p‐n junctions limits integrated sensors and artificial synapses in a monolithic device. In this work, a bipolar p‐n junction designed by employing the hydrogel/p‐GaN local contact interface with p‐GaN/(In,Ga)N heterojunction, demonstrating the bidirectional photocurrent and sensor/artificial synapse dual‐mode device successfully. After modifying Au nanoparticles, the negative (positive) photocurrent is increased by 900% (300%) under 365 nm (520 nm) light to achieve a more balanced bipolar carrier dynamic. Such a regulation of photocurrent is found to be attributed to the promotion of hydrogen evolution reaction (HER) at the hydrogel/Au/p‐GaN interface. Thus, the device achieves the ultrahigh paired‐pulse facilitation (PPF) index of 243% under self‐powered condition. Moreover, the implementation of plasticity from short‐term to long‐term demonstrates its adaptability in neural morphology visual recognition. Beyond independent working mode, the function of five classic logic gates is achieved under three‐terminal operation. Finally, an encrypted wireless communication system using dual‐channel light signals demonstrates the extensive application potential of the monolithic device. Therefore, this work presents a viable construction blueprint to meet the demands of next‐generation all‐in‐one optoelectronics for intricate application scenarios. [ABSTRACT FROM AUTHOR]

The Rician distribution, a well-known statistical distribution frequently encountered in fields like magnetic resonance imaging and wireless communications, is particularly useful for describing many real phenomena such as signal process data. In this paper, we introduce objective Bayesian inference for the Rician distribution parameters, specifically the Jeffreys rule and Jeffreys prior are derived. We proved that the obtained posterior for the first priors led to an improper posterior while the Jeffreys prior led to a proper distribution. To evaluate the effectiveness of our proposed Bayesian estimation method, we perform extensive numerical simulations and compare the results with those obtained from traditional moment-based and maximum likelihood estimators. Our simulations illustrate that the Bayesian estimators derived from the Jeffreys prior provide nearly unbiased estimates, showcasing the advantages of our approach over classical techniques. Additionally, our framework incorporates the S.A.F.E. principles – Sustainable, Accurate, Fair, and Explainable – ensuring robustness, fairness, and transparency in predictive modelling. [ABSTRACT FROM AUTHOR]

Wireless Powered Communication Networks (WPCNs) represent a transformative approach to address the energy demands of mobile and Internet of Things (IoT) devices. By integrating Nonorthogonal Multiple Access (NOMA) and Intelligent Reflecting Surfaces (IRS), we can significantly enhance system performance, extend coverage, and elevate the sum rate. NOMA efficiently utilizes the entire bandwidth by employing a power allocation strategy, whereas IRS, serving as an alternative to traditional relay amplification, further bolsters the sum rate. Despite these advancements, optimizing the sum rate introduces a nonconvex optimization challenge, primarily owing to the signal‐to‐interference‐plus‐noise ratio (SINR) complexities introduced by NOMA's Successive Interference Cancellation (SIC). Traditional convex optimization solvers, such as the CVX, struggle to address nonconvexity directly. Consequently, they were unable to produce the desired outcome. Moreover, the combination of multiple technologies to improve the sum rate complicates the optimization framework, necessitating a multitude of constraints that not only heightens the mathematical complexity but also induces errors through the requisite approximations for convexity conversion. To circumvent these hurdles, we advocate the application of a minimum constrained nonlinear multivariable function (Fmincon). This approach enables us to tackle the nonconvex problem head‐on, maintaining consistent simulation parameters while limiting constraints to two pivotal factors: joint optimization of the transmit power (PT) and transmit time (Tx). This strategic simplification mitigates complexity and minimizes errors. Our numerical analyses confirmed the efficacy of the proposed model and optimization technique. By co‐optimizing the transmission power and time, we achieved a notable sum rate. Comparative evaluations with extant models underscored the superior performance of our proposed framework, marking a significant stride in WPCN advancement. [ABSTRACT FROM AUTHOR]

Summary: The future wireless communication networks (beyond 5G) are intended to provide seamless connectivity, higher data rates, and lower latency. The intelligent reflecting surface (IRS) promises extended network coverage. The non‐orthogonal multiple access (NOMA) technique provides higher spectral efficiency and supports a larger number of users. In general, the cell‐edge users far from the base station are affected by severe fading, which may result in an outage. To overcome this issue, we propose an IRS‐aided device‐to‐device (D2D)‐enabled two cells coordinated NOMA system in which a common cell‐edge user acts as D2D receiver. The cell‐edge user receives the signals from near users, IRSs, and both base stations to achieve better diversity. We analyze the outage probability of cell‐edge user, while all the fading channels are assumed Nakagami‐ m and obtain a closed‐form expression at higher signal‐to‐noise ratios. We develop an algorithm to find the ergodic capacity of the cell‐edge user. We validate the mathematical expressions with simulation results and see a substantial improvement in outage performance over the existing systems. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a novel strategy of video communication over a 5G platform of new radio (NR) is developed, and it is named ViNR. With the support of optimization on the ViNR quality of service (QoS) system design, we stretched the outdated R‐D optimization to a novel delay‐distortion‐rate optimization (DDRO) control method. The entire model is partitioned with two types of coding: source coding and channel coding. For source coding, we affianced the inter‐frame prediction method of independent predicted frames (IPPPP) with Lagrange multiplier optimization. Channel coding is intricate with the minimization of delay‐distortion and getting the most out of the rate using resource allocation optimization in terms of sub‐slice allocation. To perform this sub‐slice resource assignment with optimization of DDR, the isolation resource allocation is premeditated in this work to ensure the service level profile of various groups of resource slots or grids dealing with the subject of middling delay and rate. The widespread simulation results divulge that the proposed algorithm NR‐DDRO achieves better QoS parameters of delay, distortion, and rate with the metrics of end‐to‐end distortion, encoding Y‐PSNR, encoding bit rate, encoding time, end‐to‐end PSNR, optimization time, and complete computation time. [ABSTRACT FROM AUTHOR]

Summary: Massive multiple‐input multiple‐output (MA‐MIMO) has been hailed as an auspicious technology for the future generation of wireless communications because it can considerably increase the capacity of the communication network. However, using the maximum likelihood (ML) direction‐of‐arrival (DOA) estimate method is severely constrained in actual systems because of the computationally expensive multi‐dimensional searching procedure. This paper proposes a novel approach to estimate DOA and channels by incorporating deep learning into the MA‐MIMO system. Here, a deep belief network (DBN) is used to learn both the spatial structures in the angle domain and the statistics of the wireless channel through both online and offline learning procedures. Also, a bald eagle search (BES) Optimization is used along with DBN to attain high precision through optimal training. The proposed model can estimate the channel based on the predicted DOA and the complex gain. According to numerical results, the suggested method performs significantly better than state‐of‐the‐art methods, particularly in tough conditions like low signal‐to‐noise ratio (SNR) and a finite number of snapshots. The proposed DBN‐BES technique accomplishes less root mean square error (RMSE) as 0.01 for SNR of 5 dB in elevation calculation and 0.02 for SNR of 5 dB in azimuth calculation. Also, the proposed algorithm greatly reduces computational complexity. [ABSTRACT FROM AUTHOR]

Summary: The increasing prevalence of MIMO technology in wireless communication networks is attributed to its ability to augment system capacity and dependability. Consequently, there is a notable enthusiasm for the advancement and implementation of S‐band applications. Nevertheless, the mutual coupling between numerous antennas presents a crucial obstacle to MIMO system performance. This paper presents a novel technique that utilizes a defective ground structure with parasitic components to increase antenna isolation and gain. Additionally, an L‐shaped slot is incorporated into the patch element to enhance the antennas impedance bandwidth. Antennas are intentionally placed in a perpendicular arrangement to minimize the impact of the coupling effects. The antenna exhibits an impedance bandwidth in the frequency range of 2.62–2.79 GHz. Furthermore, the utilization of a four‐element MIMO antenna setup with a defective ground structure yields outstanding isolation properties, with values notably lower than −25 dB. To achieve an optimal MIMO performance, we assessed various diversity parameters, including diversity gain, channel capacity loss, total active reflection coefficient, and envelope correlation coefficient. The parameter values were within acceptable limits (ECC < 0.04, DG = 10 dB, TARC < 0 dB, and CCL < 0.1 bits/s/Hz). This research paper therefore offers essential insights into the design and optimization of MIMO antennas specifically for 2.7 GHz applications. [ABSTRACT FROM AUTHOR]

The paper considers the problem of forming the maximum amplitude of the electric field strength at a required point using two identical one-dimensional linear antenna arrays located orthogonally to each other and focused at one point in space. Relationships have been obtained that allow us to determine the geometric dimensions of all areas. The results of theoretical calculations of the sizes of the zone of increased electric field intensity turned out to be close to the results of simulation. For example, the size of the zone of increased electric field intensity for two orthogonal antenna arrays consisting of 20 elements, the theoretical dimensions of the zone of increased intensity were 310 mm. The simulation results showed the dimensions of this zone to be equal to 325 mm, which is explained by taking into account the influence of radiation from the other antenna array. [ABSTRACT FROM AUTHOR]

Stationary in situ measurements conducted in close proximity to the shoreline present unique challenges. The shallow depth, automated profiling and accessibility for maintenance, particularly in the context of biofouling, are key considerations. The WInch for Long-term MOnitoring (WILMO), a solution designed to meet these requirements, is therefore presented. The fully automated system keeps the sensitive devices outside of the water until a profiling cycle is initiated, reducing the available settling time for species on the surface of the sensors. The design leverages common hardware and is structured in distinct units. This feature facilitates the interchangeability of individual hardware components and the implementation of a unifying software system capable of simultaneously managing all elements of WILMO. Using wireless broadband communications, WILMO can be fully controlled remotely, allowing for adjustments to the setup and monitoring of system functionality through a special web interface. The data are transmitted to a server with adjustable frequency and a post processing tool prepares them for analysis. The system underwent rigorous testing and demonstrated effective performance in northern Bali, Indonesia, between March and December 2022, gathering physical and biogeochemical time series data. The consistency of the data is validated through comparison with other instruments to ensure data quality. The results obtained are employed to ascertain the suitability of the special flow velocity sensor in this context. WILMO is a demonstrably reliable device, easily manageable and perfectly suited for long-term coastal monitoring. [ABSTRACT FROM AUTHOR]

As the demand for high-capacity and energy-efficient wireless communications grows, the exploration of cost-effective and power-optimized hybrid digital-analog beamforming techniques for millimeter-wave massive MIMO systems has gained substantial traction. Adopting low-resolution phase shifters offers a more practical solution in terms of reducing power consumption and implementation costs. We investigate hybrid beamforming strategies for mmWave massive MIMO systems that employ low-resolution phase shifters, with a specific focus on designing and optimizing the analog beamforming component. To exploit the full potential of analog phase shifter network (APSN) in mmWave massive MIMO system while maintaining low-power consumption, we propose a two-layer APSN with low-resolution PSs to replace the conventional single-layer APSN with high-resolution PSs. Under the constraints imposed by the two-layer APSN hardware architecture, we propose a two-level codebook structure and an adaptive-weighted cross-entropy optimization algorithm that offers superior performance while substantially reducing the computational burden compared to the conventional cross-entropy optimization algorithm. We further develop two alternative schemes through the maximal gain harvest method to reduce complexity. We also investigate the case that only one steering vector is shared in the inner beamformer and present two low-complexity beamforming algorithms. Through simulations, the proposed two-layer APSN structure and the proposed algorithms have been shown to outperform existing methods, with notable effectiveness in scenarios where low-resolution phase shifters are utilized. [ABSTRACT FROM AUTHOR]

As wireless communication systems increasingly require compact and efficient antennas, conventional antenna design methods are proving difficult to meet the rigorous demands of modern applications. For this purpose, this study introduces a methodology which uses pixelated Inverted-F Antenna (IFA) inspired designs optimised through genetic algorithms to enhance performance in constrained spatial environments. As pixels the antenna features the exemplary use of Einstein Hat-shaped tiles, enabling the antenna to efficiently utilize space. A with the proposed method optimised antenna is compared to traditional IFA designs and shows improved properties like enhanced antenna gain and efficiency as well as smaller reflection coefficient offering a promising solution for future compact antenna systems in the Internet of Things and beyond. Finally, a prototype was manufactured and the scattering parameters and antenna gain were measured within an anechoic chamber. [ABSTRACT FROM AUTHOR]

ABSTRACT This review examines the advanced development and implementation of intelligent reflecting surfaces (IRSs) in smart radio environments (SREs) to enhance secure communications. IRS technology, including intelligent walls and software‐controlled metasurfaces, is designed to manipulate electromagnetic waves, thereby significantly improving wireless communication. The study highlights the importance of dynamic, nearly passive IRS, which combine multiple elements to create surfaces capable of diverse wave manipulations. Cutting‐edge techniques such as nonorthogonal multiple access (NOMA) and machine learning are employed to optimize IRS functions, enhancing secrecy rates and resilience against eavesdropping. Despite their ease of reconfiguration and affordability, IRSs are vulnerable to several security threats, a concern that has not been extensively explored in current research. This review aims to fill this gap by offering a comprehensive analysis of the security challenges associated with IRS‐enabled wireless networks. The effectiveness of IRS is compared to traditional wireless relays, with special attention to the simultaneous transmitting and reflecting intelligent reflecting surface (STAR‐IRS) model that provides 360° coverage. Key findings suggest that IRS can greatly enhance secure communications, improving wireless network performance, reliability, and adaptability. This paper underscores the pivotal role of IRS technology in the future of wireless networks, presenting new opportunities for secure and efficient communication systems. [ABSTRACT FROM AUTHOR]

Nitride ferroelectrics have recently emerged as promising alternatives to oxide ferroelectrics due to their compatibility with mainstream semiconductor processing. ScAlN, in particular, has exhibited remarkable piezoelectric coupling strength (K2) comparable to that of lithium niobate, making it a valuable choice for RF filters in wireless communications. Recently, ScAlN has sparked interest in its use for nanophotonic devices, chiefly due to its large bandgap facilitating operation in blue wavelengths coupled with promises of enhanced nonlinear optical properties such as a large second-order susceptibility (χ(2)). It is still an open question whether ScAlN can outperform oxide ferroelectrics concerning the Pockels effect—an electro-optic coupling extensively utilized in optical communications devices. In this paper, we present a comprehensive theoretical analysis and experimental demonstration of ScAlN's Pockels effect. Our findings reveal that the electro-optic coupling of ScAlN, despite being weak at low Sc concentration, may be significantly enhanced and exceed LiNbO3 at high levels of Sc doping, which points the direction of continued research efforts to unlock the full potential of ScAlN. The authors predict the Pockels effect of ScAlN with varying Sc concentration, realizing a ScAlN-on-insulator-on-silicon material platform, which allows the formation of low-loss, electrically-tunable microring resonators for accurate measurement of ScAlN's Pockels coefficients. [ABSTRACT FROM AUTHOR]

5G and 6G promise to be catalysts for the Internet of Things (IoT), enabling ultra‐massive and mission‐critical IoT. The demands of new IoT applications and the large number of connected objects being announced will exacerbate the thorny issue of spectrum scarcity in wireless communications. Cognitive radio (CR) is a revolutionary technology that promises to mitigate the problem of spectrum scarcity through more efficient use of spectrum. Integrating CR into the IoT allows objects to opportunistically access spectrum resources already allocated to a Primary User (PU) without causing interference. Spectrum sensing (SS) allows objects to be aware of the PU's spectrum occupancy status. In radio environments where the PU signal is subject to multipath and shadowing effects that degrade the channel between the PU and objects, SS performed by a single object could be inaccurate and lead to incorrect decisions about the PU's status. Cooperative spectrum sensing (CSS) has been proposed to improve detection performance. However, this cooperation between objects has opened the way to a new form of attack known as the Spectrum Sensing Data Falsification (SSDF) or Byzantine attack. In a SSDF attack, attackers falsify their local sensing results before sharing them in the CSS. This attack is very harmful to the CSS and can lead to a loss of spectrum opportunities or interference with the PU. In this paper, from the attack point of view, a sophisticated Byzantine attack model that generalizes well the simple attack strategies has been proposed and allows an attacker to implement other attack strategies. From a defense point of view, a new and innovative Weighted Sequential Hypothesis Testing (WSPRT) scheme has been suggested. This ensures the security of the CSS while significantly reducing the average number of samples required for overall decision‐making in a very hostile IoT network. The results obtained from simulations carried out in various attacks scenarios show that the proposed secure CSS scheme requires at most six samples to detect the state of the PU without error when the proportion of attackers reaches 80%. This performance far exceeds that of other defense mechanisms such as classic WSPRT, SPRT, and majority rule, with which we have compared it under the same conditions. In general, for the classic WSPRT, SPRT, and majority rule mechanisms, the error rate starts to deteriorate at ratio 40% of attackers and the number of samples is greater than six and reaches 50. [ABSTRACT FROM AUTHOR]

Vectorial structured beam, which possesses diverse inhomogeneous spatial field distributions, has been developed into an advanced technology for particle trapping, optical communication, and quantum information. However, most of the related studies are based on static devices that can only generate structured light with fixed field distributions. To break through this restriction, the study proposes and experimentally demonstrates a reflection‐type spin‐independent programmable metasurface (SIPM) that can generate arbitrary vector vortex beams (VVBs) dynamically in microwave frequencies. By controlling the working states of loaded positive‐intrinsic‐negative (PIN) diodes, the metasurface can realize real‐time and spin‐independent manipulations of amplitude and phase of the reflected waves. Therefore, any desired VVBs can be achieved by dynamically controlling the superimposition of left‐ and right‐handed reflected circularly polarized vortexes. The proposed SIPM exhibits powerful abilities in modulating the vectorial structured beams in the microwave band, and may bring potential technological innovations for the future spintronics, imaging display, optical computing, and wireless communications. [ABSTRACT FROM AUTHOR]

Nowadays, efficient spectrum usage is one of the most important design principles to take into account in wireless communications due to the exponential growth of mobile devices. In that sense, solutions such as Non-Orthogonal Multiple Access (NOMA) and cognitive radio (CR) have been proposed. In essence, NOMA allows some interference level by using non-orthogonal resource allocation with a tolerable increase in receiver complexity employing successive interference cancellation (SIC). In this work, a novel mathematical model of teletraffic for users performing accessment, simultaneously, by means of Orthogonal Multiple Access (OMA) and NOMA, is developed using a Markovian process that considers bursts of arrivals to model the access schemes. This novel procedure implies a closed-form solution of the proposed system compared to other works where these parameters are estimated assuming the moment generating function obtained with approximation models. The model is validated with a discrete event simulator, considering different scenarios and simulation conditions. The simulation results are in agreement with the mathematical solution proposed. [ABSTRACT FROM AUTHOR]

Cellular network scheduling is crucial for wireless deployments like 4G, 5G, and 6G and is a challenging resource allocation task performed by the scheduler located at the base stations. The scheduler must balance two critical metrics, throughput and fairness, which often conflict, as maximizing throughput favors users with better channel conditions, while ensuring fairness requires allocating resources to those with poorer channel conditions. The proportional fairness metric is a prominent scheduling approach that aims to balance these competing metrics with minimal compromise. The common strategy to attain proportional fairness relies on a greedy approach in which each resource block is allocated to the user who maximizes the proportional fairness criterion. With such a strategy, the scheduler can ensure that the resources allocated to the users at each time instance maximize the proportional fairness metric. However, users can usually tolerate some delay and are willing to accept temporary fairness imbalances if they ultimately improve their performance, provided that the fairness criterion is maintained over time. In this paper, we propose a new scheduler that uses reinforcement learning to enhance proportional fairness. The suggested scheduler considers both current and predicted future channel conditions for each user, aiming to maximize the proportional fairness criterion over a set of predefined periodic time epochs. Specifically, by learning patterns in channel fluctuations, our reinforcement learning-based scheduler allocates each resource block not to the user who maximizes the instantaneous proportional fairness metric, but to the user who maximizes the expected proportional fairness metric at the end of the current time epoch. This approach achieves an improved balance between throughput and fairness across multiple slots. Simulations demonstrate that our approach outperforms standard proportional fairness scheduling. We further implemented the proposed scheme on a live 4G eNodeB station and observed similar gains. [ABSTRACT FROM AUTHOR]

This article examines the transformative potential of integrating reconfigurable intelligent surfaces (RISs) into sixth-generation (6G) wireless non-terrestrial networks (NTNs). The focus is on the RIS's capability to address diverse user requirements, including secure data transmission, power efficiency, extended coverage, and enhanced data rates. The paper delves into the synergy between RISs and NTNs, emphasizing key components like multiple-input multiple-output (MIMO) systems and advanced radio communications. Additionally, it highlights the crucial role of artificial intelligence (AI) and machine learning (ML) in optimizing RIS-based beamforming to solve scientific and engineering challenges while ensuring energy efficiency and sustainability in NTN operations. By positioning RISs as a key enabler in shaping the future of wireless communication systems, this research underscores their significance in unlocking the full potential of NTNs and advancing next-generation wireless communications. This paper contributes valuable insights and projections for future research directions, highlighting RISs' potential to revolutionize NTNs for 6G technologies. [ABSTRACT FROM AUTHOR]

With improvements in medical environments and the widespread use of smartphones, interest in wearable biosensors for continuous body monitoring is growing. We developed a wearable multiplexed bio-sensing system that non-invasively monitors body fluids and integrates with a smartphone application. The system includes sensors, readout circuits, and a microcontroller unit (MCU) for signal processing and wireless communication. Potentiometric and amperometric measurement methods were used, with calibration capabilities added to ensure accurate readings of analyte concentrations and temperature. Laser-induced graphene (LIG)-based sensors for glucose, lactate, Na+, K+, and temperature were developed for fast, cost-effective production. The LIG electrode's 3D porous structure provided an active surface area 16 times larger than its apparent area, resulting in enhanced sensor performance. The glucose and lactate sensors exhibited high sensitivity (168.15 and 872.08 μAmM−1cm−2, respectively) and low detection limits (0.191 and 0.167 μM, respectively). The Na+ and K+ sensors demonstrated sensitivities of 65.26 and 62.19 mVdec−1, respectively, in a concentration range of 0.01–100 mM. Temperature sensors showed an average rate of resistance change per °C of 0.25%/°C, within a temperature range of 20–40 °C, providing accurate body temperature monitoring. [ABSTRACT FROM AUTHOR]

This paper proposes a dual-band patch antenna with combined self-decoupling and filtering properties, designed to suppress mutual coupling between two antenna elements both within the same dual-band and across different dual-bands. Initially, a dual-band aperture-coupled filtering patch antenna is designed, featuring a forked short-circuited SIR feedline with a quarter-wavelength open-ended stub and a U-shaped patch with two U-slots, which generate three controllable radiation nulls while introducing two additional resonant modes. The design steps are also provided in detail. Subsequently, the low mutual coupling phenomenon of two vertically placed aperture-coupled patch antennas is investigated, successfully developing a high-isolated dual-band two-element MIMO array I. Furthermore, the other quad-band two-element MIMO array II is designed, which utilizes the filtering response to significantly reduce mutual coupling across four bands. Finally, a dual-band filtering patch antenna element and two two-element MIMO arrays are fabricated and measured. The measurements and simulations validate the antenna's low mutual coupling performance in multi-band MIMO arrays and demonstrate its strong potential for future wireless communication applications. [ABSTRACT FROM AUTHOR]

This paper employs the Sine Cosine Algorithm, a recent meta-heuristic method, to enhance the radiation properties of concentric elliptical antenna arrays in far-field applications, such as smart grid wireless communication and the Internet of Things. It focuses on minimizing the Sidelobe Level, a key parameter in antenna radiation, to mitigate unwanted signals and interference. The proposed method, known for its global optimization effectiveness, tackles the challenge of designing sparse multiple concentric elliptical arrays. By using the Sine Cosine Algorithm, the inter-element spacing and optimal determination of amplitude coefficients are achieved, resulting in a radiation pattern with reduced sidelobe level. To showcase the adaptability and superior performance of our proposed algorithm, we systematically evaluated its effectiveness across four distinct sets of concentric elliptical antenna arrays. These arrays comprise varying numbers of elements: (6, 12, 18 elements, 6, 12, 18, 24 elements, 6, 12, 18, 24, 30 elements and 6, 12, 18, 24, 30, 36 elements) with and without a central element. Using the sine cosine algorithm, we synthesize arrays and compare their sidelobe level and First Null Beam Width values with those from recent methods. Our findings consistently shows that the proposed algorithm consistently outperforms alternatives, yielding significantly lower sidelobe level values in all comparisons. [ABSTRACT FROM AUTHOR]

Massive multiple‐input multiple‐output and non‐orthogonal multiple access (MIMO‐NOMA) with low‐resolution analog‐to‐digital converters (ADCs) have been widely considered for the next‐generation wireless communication systems. However, the performance of the system including power‐scaling law has not been well investigated for the practical low complexity receivers. Employing the additive quantization noise model, we derive asymptotic approximate expressions of the spectrum efficiency for the system with group successive interference cancellation (GSIC) receivers over Rician fading channels. Based on these approximations, we conduct a unified asymptotic analysis for the system with linear, SIC, and GSIC receivers. The analysis reveals the transmission power can be scaled by the number of antennas for the system with GSIC receivers and shows the effects of crucial parameters including the number of groups, resolution bits, and antennas on the performance. Given a quality of service, the minimum data transmission power is also calculated for each user and the corresponding approximate power allocation is derived. The asymptotic analysis and the accuracy of the power allocation approximation are then verified by simulation results. Numerical results also demonstrate that high spectrum efficiency and energy efficiency can be achieved by the system with medium‐resolution ADCs and low complexity maximum ratio combining‐GSIC receivers with a small number of groups. [ABSTRACT FROM AUTHOR]

Recent advancements in wireless communication have markedly increased data throughput and decreased latency in progressing toward sixth‐generation (6G) networks, wherein the terahertz (THz) waveband offers significant potential. However, conventional THz sensors often suffer from high noise, low responsivity, and low spectrum efficiency, limiting their effectiveness for THz applications. Here, to address these challenges, a magnetic‐enhanced frequency‐selective is developed THz sensor by depositing an Au‐enhanced active layer of MoTe2 on a designed 3D printing high‐depth micro‐helical stepped structure. This sensor, featuring four characteristic frequency points and an effective area of 107.12 mm2, demonstrated noticeable improvements under a 0.145 mT magnetic field at 0.1 THz: optical responsivity improved by 413.23% (from 3.32 to 17.03 MV W−1), noise equivalent power decreased by 80.51% (from 49.16 to 9.58 pW Hz−1/2), and the detectivity reached 3.30 × 1010 cm·Hz1/2·W−1. This work highlights the potential of integrating 3D microstructures with novel topological materials for practical 6G communication. [ABSTRACT FROM AUTHOR]

As terahertz (THz) technology has been widely considered as a key candidate for future sixth‐generation wireless communication networks, THz modulators show profound significance in wireless communication, data storage, and imaging. In special, dynamic tuning of THz waves through 2D electron gas (2DEG) incorporated with a hybrid design of metasurface has attracted keen interest due to the combined merits of deliberate structural design, rapid switching speed and the process compatibility. Current meta‐modulator enables very high modulation depth but encounter limited bandwidth. In this paper, by taking into account the co‐functional effects of temperature and voltage‐dependent dynamic control on transmission amplitude, a 2DEG‐based GaN‐on‐Si modulator with two switchable operational states (or four modes) of active wave control is proposed. Under cryogenic temperature conditions, the proposed device exhibits prominent 2D plasmons characteristics with switchable transitions between the gated mode and ungated mode for active control. Under room temperature conditions, the proposed device exhibits non‐resonance broadband spectra characteristics with tunable transitions between the linearity mode and depletion mode for transmission control. The scheme provides an option for the development of the actively tunable THz meta‐modulator and paves a way for the robust multifunctionality of electrically controllable THz switching, and biosensors. [ABSTRACT FROM AUTHOR]

A novel compact rectangular fractal-shaped antenna for tri-band wireless communication applications is developed in this article. The proposed fractal shaped is achieved by cutting two rectangular slots in the rectangular monopole. Additionally, a stub is introduced in the bottom side of the antenna to enhance the impedance bandwidth of the acquired three bands. The developed antenna has a compact size 22 × 34 × 1.6 mm3. The CST MWS is used to design the antenna and its characteristics including S11, current distribution, radiation characteristics are exposed and analysed. To demonstrate that the simulation outcomes are reliable, the suggested antenna is manufactured and put through testing on an E5071C VNA. Additionally, the results of the experiments demonstrate that the designed antenna offers three impedance bandwidths 2.25–2.96 GHz, 3.56–4.01 GHz, and 4.6–5.86 GHz, which shields all the LTE, WLAN, WiMAX, and C-band applications. The proposed tri-band fractal antenna also provides good gain at the operating frequencies and an omnidirectional radiation pattern. [ABSTRACT FROM AUTHOR]

Switching-mode power amplifiers have provided unprecedented opportunities for modern wireless communication technology. However, its single-ended structure suffers from significant harmonic interferences on signal transmission; in some cases, higher return loss caused by the impedance mismatch may damage or even destroy the device directly. Here it shows, analytically and experimentally, a broadband push–pull parallel-circuit (PC) Class-E power amplifier (PA) which can present high efficiency and flatness gain over a wide frequency range. Based on the broadband capability of the proposed structure, a highly-efficient push–pull PC Class-E PA combining single reactance compensation technique and Chebyshev low-pass impedance matching network (MN) is designed and fabricated. Experimental results demonstrated that a drain efficiency of 93.71–94.62% operating from 7.0 to 9.4 MHz, as well as output power (Pout) of 42.1–44.57 dBm and power gain of 14.1–16.57 dB are obtained. The measurement results show good agreements with the simulation results, which may be a potential candidate for electronic article surveillance (EAS) applications operating in the high-frequency band. [ABSTRACT FROM AUTHOR]

Wireless rechargeable sensor network (WRSN) is one of the most important networks in today's world for extending network lifetime. To ensure a collision-free contention in WRSN, this paper proposes the Contention Window Optimization using the Cuttlefish Algorithm (CWO-CA) and addresses existing issues such as the capture effect, the fairness problem, and the queue hike. For safe channel access, the fitness function of CWO-CA is proposed using the retransmission count, queue size, and residual energy of the sensor node. The proposed algorithm divides the Contention Window interval into two halves based on the fitness function, and the nodes are assigned in either half to guarantee service differentiation. The fitness function among groups of the proposed algorithm constitutes the best fitness value. By selecting the best fitness value, the proposed algorithm facilitates adaptive contention management by dynamically balancing resource utilization of the network with the optimal result. The nodal behavior of CWO-CA has been modeled using a discrete Markov model and also simulated to measure throughput, packet delivery ratio, packet loss ratio, average queue size, residual energy, and delay. These results confirm that the proposed CWO-CA algorithm attained better performance than other existing algorithms. [ABSTRACT FROM AUTHOR]

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The infrastructure to support human societies' safety, health, and utility supply can not be negotiated, and to have basic reliability in monitoring tasks, plural or dual surveillance, rooted in biologic senses, is needed. To fit the contemporary wireless communication, MIMO (multi-in multi-out) being incorporated with suggested network prototypes, aimed especially on the naturally bipartite Honeycomb Tori (HT) for cellular communications, to prevent information loss, interference, unexpected changes caused by such as clogged water. The mutually independent Hamiltonian Path (MIHP) property can be used for parallel processing and supporting cipher coding to offer efficiency, integrity, and privacy. Isomorphism between Honeycomb Tori and Generalized Honeycomb Tori (GHT) is utilized; mathematical HT(m) m ≥ 2 can be presented as GHT (m, 6m, 3m). Setting rational configurations, incremental scalability qualifying, it is proved that GHT (m, n, n/2) "even m, n ≥ 12" and "odd m > 1, n ≥ 10," which naturally include full Honeycomb Tori, can have a property dual MIHP. [ABSTRACT FROM AUTHOR]

Ambulance-based telestroke may be a promising solution to improving stroke care. We assessed the technical feasibility and reliability of prehospital evaluations using commercial mobile phones with fifth-generation wireless communication technology. Six standardized patients portrayed scripted stroke scenarios during ambulance transport in an urban city and were remotely evaluated by independent raters using tablets (three neurologists and three emergency physicians) in a hospital, assisted by paramedics (trained in National Institute of Health Stroke Scale [NIHSS] assessment) in the ambulance; commercial cellular networks were utilized for videoconferencing transmission. The primary outcomes were mean difference (MD) and correlation of NIHSS scores between the face-to-face and remote assessments. We also examined the Bland-Altman plot for itemized NIHSS components, and Kaplan–Meier curves were used to compare the differences in the duration of the two evaluations between neurologists and emergency physicians. We conducted 32 ambulance runs and successfully completed all NIHSS examinations. No significant difference was found between the face-to-face and remote evaluations (MD, 0.782; 95% confidence interval [CI], −0.520–0.395). The correlation of NIHSS scores between the two methods was 0.994 (95% CI, 0.945–1.026), and three items exhibited the highest frequency of runs, with score differences between the two methods. There were no significant differences between neurologists and emergency physicians in the mean evaluation duration and NIHSS scores for the two methods. Prehospital evaluation using commercial mobile phones with fifth-generation wireless communication technology is feasible and reliable during ambulance transport in urban areas. Emergency physicians and neurologists performed similarly in stroke evaluations. [ABSTRACT FROM AUTHOR]

Beam-steered infrared (IR) light communication has gained tremendous attention as one of the solutions of congested wireless communication traffic. High performance active beam-steering devices play a crucial role in data allocation and exchange. Conventional beam-steering devices such as spatial light modulator (SLM) and micro-electrical mechanical system (MEMS) mirror and the current emerging nonmechanical beam-steering metasurface-based devices are challenging to realize a large tunable steering angle beyond several degrees, which significantly hinders the spatial application of optical wireless communications (OWC). Herein, an angle-magnified liquid crystal (LC) metadevice consisting of LC metasurfaces and a liquid crystal on silicon (LCoS) is proposed to realize active beam steering with a tunable large field of view (FOV). Based on the angle-magnified tunable LC metadevice, an intelligent bidirectional high-speed OWC system is experimentally demonstrated, achieving an actively enlarged FOV of 20° × 20°, with a data rate of 200 Gbps over the S/C/L band for both uplink and downlink transmission over a propagation distance of 1.5 m in free space. The proposed OWC system opens a new avenue for the future high performance wireless data transmission. [ABSTRACT FROM AUTHOR]

With the rapid increase in the number of various terminal devices in distribution systems, the important impact of communication networks on power supply reliability in cyber–physical distribution systems (CPDSs) is becoming increasingly prominent. The traditional wired communication method makes it difficult to meet the demand in some scenarios due to high cost and construction difficulty. For this reason, this study evaluated the reliability of power distribution cyber–physical systems, considering fifth-generation (5G) mobile communication technology wireless access conditions. First, a reliability model of a communication channel in a 5G communication network was established, and the indirect impact of information system failure on the power distribution system was analyzed. Secondly, a reliability assessment method based on the improved least path method was devised by combining switch action failure, self-healing processing, and load transfer. The simulation results show that 5G communication technology has significant advantages in improving system reliability, and the proposed method is closer to the development direction of future power distribution systems, which provides an effective reference basis for the optimized operation of power distribution cyber–physical systems. [ABSTRACT FROM AUTHOR]

Wireless Sensor Networks (WSNs) are rapidly being integrated into various fields, significantly impacting and facilitating many aspects of human life. However, the increasingly prominent security issues associated with WSNs have become a significant challenge. This paper provides an in-depth analysis of the security challenges faced by WSNs in resource constrained and open communication environments. As a key component of the Internet of Things (IoT), a WSN can perceive, collect and transmit physical environmental data in real-time, and is widely used in military, medical, agricultural and other fields. However, the insecurity of communication channels and unauthorized user access pose severe threats to network security and data integrity. To address these challenges, this paper proposes a provably secure two-factor authentication protocol. This protocol utilizes a Chebyshev chaotic map and a two-factor authentication mechanism, which not only enhances security in WSNs but also improves authentication efficiency. The protocol is validated through security proof and performance experiments, demonstrating excellent security, functionality and efficiency. This provides strong support for secure and efficient communication in WSNs across various application scenarios. [ABSTRACT FROM AUTHOR]

Traditional automatic modulation classification methods operate under the closed-set assumption, which proves to be impractical in real-world scenarios due to the diverse nature of wireless technologies and the dynamic characteristics of wireless propagation environments. Open-set environments introduce substantial technical challenges, particularly in terms of detection effectiveness and computational complexity. To address the limitations of modulation classification and recognition in open-set scenarios, this paper proposes a semi-supervised open-set recognition approach, termed SOAMC (Semi-Supervised Open-Set Automatic Modulation Classification). The primary objective of SOAMC is to accurately classify unknown modulation types, even when only a limited subset of samples is manually labeled. The proposed method consists of three key stages: (1) A signal recognition pre-training model is constructed using data augmentation and adaptive techniques to enhance robustness. (2) Feature extraction and embedding are performed via a specialized extraction network. (3) Label propagation is executed using a graph convolutional neural network (GCN) to efficiently annotate the unlabeled signal samples. Experimental results demonstrate that SOAMC significantly improves classification accuracy, particularly in challenging scenarios with limited amounts of labeled data and high signal similarity. These findings are critical for the practical identification of complex and diverse modulation signals in real-world wireless communication systems. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless communication and big data analysis technologies, the storage of massive amounts of data relies on third-party trusted storage, such as cloud storage. However, once data are stored on third-party servers, data owners lose physical control over their data, making it challenging to ensure data integrity and security. To address this issue, researchers have proposed integrity auditing mechanisms that allow for the auditing of data integrity on cloud servers without retrieving all the data. To further enhance the availability of data stored on cloud servers, multiple replicas of the original data are stored on the server. However, in existing multi-replica auditing schemes, there is a problem of server fraud, where the server does not actually store the corresponding data replicas. To tackle this issue, this paper presents a formal definition of authentic replicas along with a security model for the authentic-replica sampling mechanism. Based on time-lock puzzles, identity-based encryption (IBE) mechanisms, and succinct proof techniques, we design an authentic replica auditing mechanism. This mechanism ensures the authenticity of replicas and can resist outsourcing attacks and generation attacks. Additionally, our schemes replace the combination of random numbers and replica correspondence tables with Linear Feedback Shift Registers (LFSRs), optimizing the original client-side generation and uploading of replica parameters from being linearly related to the number of replicas to a constant level. Furthermore, our schemes allow for the public recovery of replica parameters, enabling any third party to verify the replicas through these parameters. As a result, the schemes achieve public verifiability and meet the efficiency requirements for authentic-replica sampling in multi-cloud environments. This makes our scheme more suitable for distributed storage environments. The experiments show that our scheme makes the time for generating copy parameters negligible while also greatly optimizing the time required for replica generation. As the amount of replica data increases, the time spent does not grow linearly. Due to the multi-party aggregation design, the verification time is also optimal. Compared to the latest schemes, the verification time is reduced by approximately 30%. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs), also known as drones, have become instrumental in various domains, including agriculture, geographic information systems, media, logistics, security, and defense. These UAVs often rely on wireless communication networks for data transmission, making them vulnerable to cyberattacks. To address these challenges, it is necessary to detect potential threats by analyzing the encrypted Wi-Fi traffic data generated by UAVs. This study aimed to develop a linear SVM model that is enhanced with explainable artificial intelligence (XAI) techniques and fine-tuned using Bayesian optimization for intrusion detection systems (IDSs); the model is specifically designed to identify malware threats targeting UAVs. This research utilized encrypted Wi-Fi traffic data derived from three different UAV networks, namely, Parrot Bebop 1, DBPower UDI, and DJI Spark, while considering unidirectional and bidirectional communication flow modes. SVM-based intrusion detection models have been modeled on these datasets, identified their key features using the local interpretable model-agnostic explanations (LIME) technique, and conducted a cost analysis of the proposed modeling approach. The incorporation of the LIME method enabled to highlight the features that are highly indicative of cyberattacks and provided valuable insights into the importance of each feature in the context of intrusion detection. In conclusion, this interpretable IDS model, fine-tuned with Bayesian optimization, demonstrated its superiority over the state-of-the-art methods, proving its efficacy in detecting and mitigating threats to UAVs while offering a cost-effective solution. [ABSTRACT FROM AUTHOR]

RF power amplifier (RF PA) finds its application in almost all the areas of electronics, mobile communication being identified as a major area. The paper performs a comparative efficiency analysis of RF power amplifiers operating with a fixed bias and an envelope tracking bias. Simulations are performed using Keysight advanced design system (ADS) tool. A class a RF PA operating at a 12 dB gain is fixed for the work. 16 QAM LTE signal operating at 5 MHz input frequency, with a peak to average power ratio (PAPR) of 6.0 dB is used as input signal. An envelope simulation at 2.5 GHz is performed on the RF power amplifier. Simulation result shows an improvement of 12% in power added efficiency (PAE) at 6 dB back-off and 6.422% in mean PAE while using envelope tracking power amplifiers, compared to RF PA with fixed supply. Envelope tracking power amplifiers reduced AM/AM distortions also by a factor of 0.248. The results obtained are much better than that obtained using a conventional RF PA with fixed bias. RF PA being the most power dissipative block in a mobile handset, improving its efficiency contributes directly to a great improvement in the battery lifetime of mobile phones. The major challenges faced by envelope tracking PA (ETPA) designers in achieving this efficiency improvement is also delineated in the paper. [ABSTRACT FROM AUTHOR]

In the domain of 5G/6G wireless communications, mobile edge computing (MEC) technology is widely utilized for efficient data transmission. Unmanned aerial vehicles (UAVs) have emerged as the most recent transmission carriers in this landscape. However, the challenges associated with UAV deployment and path planning are often regarded as NP-hard, nonconvex, and nonlinear problems. Traditional optimization techniques struggle to address these complexities effectively. To address this issue, this study proposes "Edge-UAV", a novel mobile edge computing system specifically designed for UAVs. The primary objective of Edge-UAV is to minimize energy consumption and optimize the operational efficiency of UAVs. To achieve this goal, this study introduces a two-stage optimization strategy and a nonhovering transmission strategy. First, the coordinate updating operation of the UAVs' hovering points is decoupled from the path planning task. Additionally, the perturbation-inheritance algorithm is employed to enhance the coordinate updating process. In the second stage, the nonhovering transmission strategy enables UAVs to perform data transmission tasks while in flight, effectively optimizing their working time. This paper provides a detailed elucidation of the roles played by these innovative strategies within the Edge-UAV system. To assess the superiority of the proposed strategies, eight sets of comparative experiments involving 60–200 individual devices awaiting data transmission are conducted. The experimental results demonstrate the significant advantages of the Edge-UAV system in terms of reducing total energy consumption and optimizing the operational hours of UAVs. Through comprehensive experimentation and analysis, this study contributes to the advancement of UAV-assisted mobile edge computing in 5G/6G wireless communication networks. The proposed strategies exhibit promising potential for enhancing the efficiency and performance of UAVs. [ABSTRACT FROM AUTHOR]