This paper proposes a quantitative reconfigurability evaluation method for control systems with actuator saturation and additive faults from the perspective of system stability.Placing the saturated feedback law in th...This paper proposes a quantitative reconfigurability evaluation method for control systems with actuator saturation and additive faults from the perspective of system stability.Placing the saturated feedback law in the convex hull of a group of auxiliary linear controls,the sufficient reconfigurability conditions for the system under additive faults are derived using invariant sets.These conditions are then expressed as linear matrix inequalities(LMIs)and applied to quantify the degree of reconfigurability for the fault system.The largest fault magnitude for which the system can be stabilized,the largest initial state domain from which all the trajectories are convergent,and the minimum final state domain to which the trajectories will converge are investigated.The effectiveness of the proposed method is illustrated through an application example.展开更多
The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and dynamic.Modular Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in ...The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and dynamic.Modular Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in several aspects,and may become the next generation of spacecraft systems with efficient design,fast deployment,flexible application,and convenient management.This paper reviews the development and technology of MRS from three aspects:Modularity,reconfigurability,and autonomy.Despite the progress of research on MRS,there is still a lack of unified standards and little understanding of related concepts.Based on the understanding of basic concepts,the studies conducted on MRS are reviewed to identify technical requirements and solutions.Aiming at the future development trend of MRS,a novel modular selfreconfigurable spacecraft,referred to as MagicSat,is proposed.Furthermore,the MagicSat system composition,advantages,and application prospects are studied.The enabling technologies and major challenges of MRS are further analyzed in terms of modularization,integrated management,and self-reconfiguration technologies.Finally,the future development trend of MRS technology is predicted,and corresponding suggestions are provided.展开更多
The photonic frequency-interleaving(PFI)technique has shown great potential for broadband signal acquisition,effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interlea...The photonic frequency-interleaving(PFI)technique has shown great potential for broadband signal acquisition,effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interleaving paradigm.However,current comb-based PFI schemes have complex system architectures and face challenges in achieving large bandwidth,dense channelization,and flexible reconfigurability simultaneously,which impedes practical applications.In this work,we propose and demonstrate a broadband PFI scheme with high reconfigurability and scalability by exploiting multiple free-running lasers for dense spectral slicing with high crosstalk suppression.A dedicated system model is developed through a comprehensive analysis of the system non-idealities,and a cross-channel signal reconstruction algorithm is developed for distortion-free signal reconstruction,based on precise calibrations of intra-and inter-channel impairments.The system performance is validated through the reception of multi-format broadband signals,both digital and analog,with a detailed evaluation of signal reconstruction quality,achieving inter-channel phase differences of less than 2°.The reconfigurability and scalability of the scheme are demonstrated through a dual-band radar imaging experiment and a three-channel interleaving implementation with a maximum acquisition bandwidth of 4 GHz.To the best of our knowledge,this is the first demonstration of a practical radio-frequency(RF)application enabled by PFI.Our work provides an innovative solution for next-generation software-defined broadband RF receivers.展开更多
This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raph...This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raphson search rule(NRSR)to boost the exploration process,especially in search spaces with more local regions,and boost the exploitation with adaptive parameters alternating with random parameters in the original Puma.The effectiveness of the introduced IPuma is confirmed through comprehensive evaluations on the CEC’20 benchmark problems.It shows superior performance compared to both established and modern metaheuristic algorithms in terms of effectively navigating the search space and achieving convergence towards near-optimal regions.The findings indicated that the IPuma algorithm demonstrates considerable statistical promise and surpasses the performance of competing algorithms.In addition,the proposed IPuma is utilized to reconfigure a 9×9 PV array that operates under different shade patterns,such as lower triangular(LT),long wide(LW),and short wide(SW).In addition to other programmed approaches,such as the Whale optimization algorithm(WOA),grey wolf optimizer(GWO),Harris Hawks optimization(HHO),particle swarm optimization(PSO),gravitational search algorithm(GSA),biogeography-based optimization(BBO),sine cosine algorithm(SCA),equilibrium optimizer(EO),and original Puma,the indicated method is contrasted to the traditional configurations of TCT and Sudoku.In addition,the metrics of mismatch power loss,maximum efficiency improvement,efficiency improvement ratio,and peak-to-mean ratio are calculated to assess the effectiveness of the indicated approach.The proposed IPuma improved the generated power by 36.72%,28.03%,and 40.97%for SW,LW,and LT,respectively,outperforming the TCT configuration.In addition,it achieved the best maximum efficiency improvement among the algorithms considered,with 26.86%,21.89%,and 29.07%for the examined patterns.The results highlight the superiority and competence of the proposed approach in both convergence rates and stability,as well as applicability to dynamically reconfigure the PV system and enhance its harvested energy.展开更多
Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations...Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations remain in unit-level reconfiguration,multiaxial force and motion sensing,and robust operation across dynamically changing or irregular surfaces.Herein,we develop a reconfigurable omnidirectional triboelectric whisker sensor array(RO-TWSA)comprising multiple sensing units that integrate a triboelectric whisker structure(TWS)with an untethered hydro-sealing vacuum sucker(UHSVS),enabling reversibly portable deployment and omnidirectional perception across diverse surfaces.Using a simple dual-triangular electrode layout paired with MXene/silicone nanocomposite dielectric layer,the sensor unit achieves precise omnidirectional force and motion sensing with a detection threshold as low as 0.024 N and an angular resolution of 5°,while the UHSVS provides reliable and reversible multi-surface anchoring for the sensor units by involving a newly designed hydrogel combining high mechanical robustness and superior water absorption.Extensive experiments demonstrate the effectiveness of RO-TWSA across various interactive scenarios,including teleoperation,tactile diagnostics,and robotic autonomous exploration.Overall,RO-TWSA presents a versatile and high-resolution tactile interface,offering new avenues for intelligent perception and interaction in complex real-world environments.展开更多
The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the ...The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the uncertainties in train driving and operation,this paper analyzes the relationship between the safety of heavy-haul electric locomotive hauled trains and driving and operation.It studies the auxiliary intelligent driving safety operation control methods.Through K-means to identify the characteristics of drivers'driving manipulation,the hidden Markov model adaptively adjusts the train driving and operation sequence,and conducts auxiliary driving reconstruction for heavy-haul locomotive driving and operation.Based on the train running curve and the locomotive traction/braking characteristics,it smoothly controls the exertion of the traction/braking force of heavy-haul locomotives,thereby optimizing the driving safety control of heavy-haul trains in the vehicle-environment-track system.Finally,the train operation simulation and optimized driving verification are carried out by simulating some track sections.The results show that the proposed method can correct and pre-optimize driving operations,improving the smoothness of heavy-haul trains by approximately 10%.It verifies the effectiveness of the proposed train assisted driving control reconstruction method,facilitating the smooth and safe operation of heavy-haul trains.展开更多
Three-dimensional porous foams and aerogels with high compressibilityand elasticity hold great promise for applications in pressure sensing,electromagnetic interference(EMI)shielding,and thermal insulation.However,the...Three-dimensional porous foams and aerogels with high compressibilityand elasticity hold great promise for applications in pressure sensing,electromagnetic interference(EMI)shielding,and thermal insulation.However,their widespread application is often hindered by compromised structural stabilityand inadequate fatigue resistance under repeated compression.Herein,asustainable“top-down”cell wall reconfiguration strategy is proposed to fabricatehighly elastic,fatigue-resistant,and electrically conductive lamellar wood spongefrom natural balsa wood.This strategy involves the conversion of the intrinsiccellular structure of wood into an arch-shaped lamellar architecture reinforcedby chemical cross-linking,followed by coating the lamellar scaffold with conductivepolypyrrole(PPy)via in situ polymerization.The resulting PPy-coatedcross-linked wood sponge(CWS@PPy)demonstrates reversible compressibility,excellent fatigue resistance(∼3.5%plastic deformation after 10,000 cyclesat 40%strain).The strain-induced conductivity changes in CWS@PPy enabletunable EMI shielding effectiveness under cyclic compression and also facilities high-sensitivity pressure sensing(0.72 kPa^(-1)).Additionally,CWS@PPy exhibits a low through-plane thermal conductivity of 0.037 W m^(-1)K^(-1),which can be dynamically tuned for adaptivethermal management.The proposed mechanically robust and conductive wood sponge provides a versatile and sustainable platform fornext-generation smart devices.展开更多
Reconfigurable intelligent surfaces(RISs)not only assist communication but also help the localization of user equipment(UE).This study focuses on indoor localization of UE with a single access point(AP)and multiple RI...Reconfigurable intelligent surfaces(RISs)not only assist communication but also help the localization of user equipment(UE).This study focuses on indoor localization of UE with a single access point(AP)and multiple RISs.First,we propose a two-stage channel estimation scheme where RIS phase shifts are tuned to obtain multiple channel soundings.In the first stage,the newtonized orthogonal matching pursuit algorithm extracts the parameters of multiple paths from the received signals.Then,the LOS path and RISreflected paths are identified.In the second stage,the estimated path gains of RIS-reflected paths with different phase shifts are utilized to determine the angle of arrival(AOA)at the RIS by obtaining the angular pseudo spectrum.Consequently,by taking the AP and RISs as reference points,the linear least squares estimator can locate UE with the estimated AOAs.Simulation results show that the proposed algorithm can realize centimeter-level localization accuracy in the discussed scenarios.Moreover,the higher accuracy of pseudo spectrum,a larger number of channel soundings,and a larger number of reference points can realize higher localization accuracy of UE.展开更多
Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2)...Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2) management in life-support systems of confined space.Here,a micro/nano-reconfigurable robot is constructed from the CO_(2) molecular hunters,temperature-sensitive molecular switch,solar photothermal conversion,and magnetically-driven function engines.The molecular hunters within the molecular extension state can capture 6.19 mmol g^(−1) of CO_(2) to form carbamic acid and ammonium bicarbonate.Interestingly,the molecular switch of the robot activates a molecular curling state that facilitates CO_(2) release through nano-reconfiguration,which is mediated by the temperature-sensitive curling of Pluronic F127 molecular chains during the photothermal desorption.Nano-reconfiguration of robot alters the amino microenvironment,including increasing surface electrostatic potential of the amino group and decreasing overall lowest unoccupied molecular orbital energy level.This weakened the nucleophilic attack ability of the amino group toward the adsorption product derivatives,thereby inhibiting the side reactions that generate hard-to-decompose urea structures,achieving the lowest regeneration temperature of 55℃ reported to date.The engine of the robot possesses non-contact magnetically-driven micro-reconfiguration capability to achieve efficient photothermal regeneration while avoiding local overheating.Notably,the robot successfully prolonged the survival time of mice in the sealed container by up to 54.61%,effectively addressing the issue of carbon suffocation in confined spaces.This work significantly enhances life-support systems for deep-space exploration,while stimulating innovations in sustainable carbon management technologies for terrestrial extreme environments.展开更多
The integration of High-Altitude Platform Stations(HAPS)with Reconfigurable Intelligent Surfaces(RIS)represents a critical advancement for next-generation wireless networks,offering unprecedented opportunities for ubi...The integration of High-Altitude Platform Stations(HAPS)with Reconfigurable Intelligent Surfaces(RIS)represents a critical advancement for next-generation wireless networks,offering unprecedented opportunities for ubiquitous connectivity.However,existing research reveals significant gaps in dynamic resource allocation,joint optimization,and equitable service provisioning under varying channel conditions,limiting practical deployment of these technologies.This paper addresses these challenges by proposing a novel Fairness-Aware Deep Q-Learning(FAIRDQL)framework for joint resource management and phase configuration in HAPS-RIS systems.Our methodology employs a comprehensive three-tier algorithmic architecture integrating adaptive power control,priority-based user scheduling,and dynamic learning mechanisms.The FAIR-DQL approach utilizes advanced reinforcement learning with experience replay and fairness-aware reward functions to balance competing objectives while adapting to dynamic environments.Key findings demonstrate substantial improvements:9.15 dB SINR gain,12.5 bps/Hz capacity,78%power efficiency,and 0.82 fairness index.The framework achieves rapid 40-episode convergence with consistent delay performance.These contributions establish new benchmarks for fairness-aware resource allocation in aerial communications,enabling practical HAPS-RIS deployments in rural connectivity,emergency communications,and urban networks.展开更多
Vehicular communication systems rely on secure vehicle-to-vehicle(V2V)communications for safety-critical information exchange.However,the presence of eavesdropping vehicles poses a significant challenge.This paper inv...Vehicular communication systems rely on secure vehicle-to-vehicle(V2V)communications for safety-critical information exchange.However,the presence of eavesdropping vehicles poses a significant challenge.This paper investigates the security of V2V communications in reconfigurable intelligent surface(RIS)-assisted vehicular communication systems with spectrum sharing.It proposes a three-stage alternating optimization(TSAO)algorithm to address the complex problem of multiple eavesdropped V2V links that reuse the spectrum already occupied by vehicle-toinfrastructure(V2I)links.To solve the mixed-integer and non-convex optimization problem due to coupled variables and complex constraints,the algorithm decomposes the original problem into three easily solvable sub-problems:RIS reflection coefficient optimization,vehicle transmission power optimization,and spectrum sharing optimization.First,the RIS reflection coefficients are optimized by using the penalty convex-concave procedure(CCP)method.Second,the optimal power points are determined in the power optimization sub-problem.Finally,the spectrum sharing optimization sub-problem is constructed as a weighted bipartite graph matching problem and solved by using the optimal matching algorithm.The TSAO algorithm not only maximizes the sum V2V secrecy rate but also ensures the quality-of-service(QoS)requirements of the V2I links.Simulation results validate the superiority of the proposed algorithm and highlight the improvement in the sum V2V secrecy rate achieved by utilizing RIS technology in vehicular communication systems with spectrum sharing.展开更多
Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of e...Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of editable superconducting diodes could unlock transformative applications,including dynamically reconfigurable quantum circuits that adapt to operational requirements.Here,we report the first observation of the superconducting diode effect(SDE)in LaAlO_(3)/KTaO_(3) heterostructures—a two-dimensional oxide interface superconductor with exceptional tunability.We observe a strong SDE in Hall-bar(or strip-shaped)devices under perpendicular magnetic fields(<15 Oe),with efficiencies above 40%and rectification signals exceeding 10 mV.Through conductive atomic force microscope lithography,we demonstrate reversible nanoscale editing of the SDE’s polarity and efficiency by locally modifying the superconducting channel edges.This approach enables multiple nonvolatile configurations within a single device,realizing an editable superconducting diode.Our work establishes LaAlO_(3)/KTaO_(3) as a platform for vortex-based nonreciprocal transport and provides a pathway toward designer quantum circuits with on-demand functionalities.展开更多
In the era of big data and artificial intelligence,optical neural networks(ONNs)have emerged as a promising alternative to conventional electronic approaches,offering superior parallelism,ultrafast processing speeds,a...In the era of big data and artificial intelligence,optical neural networks(ONNs)have emerged as a promising alternative to conventional electronic approaches,offering superior parallelism,ultrafast processing speeds,and high energy efficiency[1-3].However,a major bottleneck in the practical implementation of ONNs is the absence of effective nonlinear activation functions.Self-driven photodetectors have emerged as versatile optical to electrical converters,opening innovative avenues for energy-effective and flexibly integrated activation functions in ONNs through their reconfigurable optoelectronic nonlinearity.展开更多
Unmanned Aerial Vehicle(UAV)-aided communication,prized for its network reconfigurability,operational flexibility,and cost-effectiveness,is a key enabler of the low-altitude economy.However,the high possibilities of l...Unmanned Aerial Vehicle(UAV)-aided communication,prized for its network reconfigurability,operational flexibility,and cost-effectiveness,is a key enabler of the low-altitude economy.However,the high possibilities of line-of-sight links and the broadcast nature of air-ground UAV communications make it vulnerable and prone to eavesdropping by malicious nodes.展开更多
In recent years,physical unclonable function(PUF)has emerged as a lightweight solution in the Internet of Things security.However,conventional PUFs based on complementary metal oxide semiconductor(CMOS)present challen...In recent years,physical unclonable function(PUF)has emerged as a lightweight solution in the Internet of Things security.However,conventional PUFs based on complementary metal oxide semiconductor(CMOS)present challenges such as insufficient randomness,significant power and area overhead,and vulnerability to environmental factors,leading to reduced reliability.In this study,we realize a strong,highly reliable and reconfigurable PUF with resistance against machine-learning attacks in a 1 kb spinorbit torque magnetic random access memory fabricated using a 180 nm CMOS process.This strong PUF achieves a challenge-response pair capacity of 10^(9) through a computing-in-memory approach.The results demonstrate that the proposed PUF exhibits near-ideal performance metrics:50.07% uniformity,50% diffuseness,49.89% uniqueness,and a bit error rate of 0%,even in a 375 K environment.The reconfigurability of PUF is demonstrated by a reconfigurable Hamming distance of 49.31% and a correlation coefficient of less than 0.2,making it difficult to extract output keys through side-channel analysis.Furthermore,resistance to machine-learning modeling attacks is confirmed by achieving an ideal accuracy prediction of approximately 50% in the test set.展开更多
Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capa...Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capabilities.The Uniform Circular Array(UCA)enables concurrent estimation of the Direction of Arrival(DOA)in both azimuth and elevation.Given the paramount importance of stability and real-time performance in interference localization,this work proposes an innovative approach to reduce the complexity and increase the robustness of the DOA estimation.The proposed method reduces computational complexity by selecting a reduced number of array elements to reconstruct a non-uniform sparse array from a UCA.To ensure DOA estimation accuracy,minimizing the Cramér-Rao Bound(CRB)is the objective,and the Spatial Correlation Coefficient(SCC)is incorporated as a constraint to mitigate side-lobe.The optimization model is a quadratic fractional model,which is solved by Semi-Definite Relaxation(SDR).When the array has perturbations,the mathematical expressions for CRB and SCC are re-derived to enhance the robustness of the reconstructed array.Simulation and hardware experiments validate the effectiveness of the proposed method in estimating interference DOA,showing high robustness and reductions in hardware and computational costs associated with DOA estimation.展开更多
In this data explosion era,ensuring the secure storage,access,and transmission of information is imperative,encom-passing all aspects ranging from safeguarding personal devices to formulating national information secu...In this data explosion era,ensuring the secure storage,access,and transmission of information is imperative,encom-passing all aspects ranging from safeguarding personal devices to formulating national information security strategies.Leverag-ing the potential offered by dual-type carriers for transportation and employing optical modulation techniques to develop high reconfigurable ambipolar optoelectronic transistors enables effective implementation of information destruction after read-ing,thereby guaranteeing data security.In this study,a reconfigurable ambipolar optoelectronic synaptic transistor based on poly(3-hexylthiophene)(P3HT)and poly[[N,N-bis(2-octyldodecyl)-napthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)](N2200)blend film was fabricated through solution-processed method.The resulting transistor exhib-ited a relatively large ON/OFF ratio of 10^(3) in both n-and p-type regions,and tunable photoconductivity after light illumination,particularly with green light.The photo-generated carriers could be effectively trapped under the gate bias,indicating its poten-tial application in mimicking synaptic behaviors.Furthermore,the synaptic plasticity,including volatile/non-volatile and excita-tory/inhibitory characteristics,could be finely modulated by electrical and optical stimuli.These optoelectronic reconfigurable properties enable the realization of information light assisted burn after reading.This study not only offers valuable insights for the advancement of high-performance ambipolar organic optoelectronic synaptic transistors but also presents innovative ideas for the future information security access systems.展开更多
The 6G smart Fog Radio Access Network(F-RAN)is an integration of 6G network intelligence technologies and the F-RAN architecture.Its aim is to provide low-latency and high-performance services for massive access devic...The 6G smart Fog Radio Access Network(F-RAN)is an integration of 6G network intelligence technologies and the F-RAN architecture.Its aim is to provide low-latency and high-performance services for massive access devices.However,the performance of current 6G network intelligence technologies and its level of integration with the architecture,along with the system-level requirements for the number of access devices and limitations on energy consumption,have impeded further improvements in the 6G smart F-RAN.To better analyze the root causes of the network problems and promote the practical development of the network,this study used structured methods such as segmentation to conduct a review of the topic.The research results reveal that there are still many problems in the current 6G smart F-RAN.Future research directions and difficulties are also discussed.展开更多
In this paper,we examine an illegal wireless communication network consisting of an illegal user receiving illegal signals from an illegal station and propose an active reconfigurable intelligent surface(ARIS)-assiste...In this paper,we examine an illegal wireless communication network consisting of an illegal user receiving illegal signals from an illegal station and propose an active reconfigurable intelligent surface(ARIS)-assisted multi-antenna jamming(MAJ)scheme denoted by ARIS-MAJ to interfere with the illegal signal transmission.In order to strike a balance between the jamming performance and the energy consumption,we consider a so-called jamming energy efficiency(JEE)which is defined as the ratio of achievable rate reduced by the jamming system to the corresponding power consumption.We formulate an optimization problem to maximize the JEE for the proposed ARIS-MAJ scheme by jointly optimizing the jammer’s beamforming vector and ARIS’s reflecting coefficients under the constraint that the jamming power received at the illegal user is lower than the illegal user’s detection threshold.To address the non-convex optimization problem,we propose the Dinkelbach-based alternating optimization(AO)algorithm by applying the semidefinite relaxation(SDR)algorithm with Gaussian randomization method.Numerical results validate that the proposed ARIS-MAJ scheme outperforms the passive reconfigurable intelligent surface(PRIS)-assisted multi-antenna jamming(PRIS-MAJ)scheme and the conventional multiantenna jamming scheme without RIS(NRIS-MAJ)in terms of the JEE.展开更多
基金This work was supported by the National Natural Science Funds for Distinguished Young Scholars of China(61525301)the National Natural Science Fund for Excellent Young Scholars of China(62022013)the National Natural Science Foundation of China(61690215).
文摘This paper proposes a quantitative reconfigurability evaluation method for control systems with actuator saturation and additive faults from the perspective of system stability.Placing the saturated feedback law in the convex hull of a group of auxiliary linear controls,the sufficient reconfigurability conditions for the system under additive faults are derived using invariant sets.These conditions are then expressed as linear matrix inequalities(LMIs)and applied to quantify the degree of reconfigurability for the fault system.The largest fault magnitude for which the system can be stabilized,the largest initial state domain from which all the trajectories are convergent,and the minimum final state domain to which the trajectories will converge are investigated.The effectiveness of the proposed method is illustrated through an application example.
基金supported by the National Defense Science and Technology Innovation Zone of China(No.00205501).
文摘The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and dynamic.Modular Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in several aspects,and may become the next generation of spacecraft systems with efficient design,fast deployment,flexible application,and convenient management.This paper reviews the development and technology of MRS from three aspects:Modularity,reconfigurability,and autonomy.Despite the progress of research on MRS,there is still a lack of unified standards and little understanding of related concepts.Based on the understanding of basic concepts,the studies conducted on MRS are reviewed to identify technical requirements and solutions.Aiming at the future development trend of MRS,a novel modular selfreconfigurable spacecraft,referred to as MagicSat,is proposed.Furthermore,the MagicSat system composition,advantages,and application prospects are studied.The enabling technologies and major challenges of MRS are further analyzed in terms of modularization,integrated management,and self-reconfiguration technologies.Finally,the future development trend of MRS technology is predicted,and corresponding suggestions are provided.
基金National Key Research and Development Program of China(2021YFB2800800)National Key Laboratory Program(E13D01012F)+4 种基金National Natural Science Foundation of China(62104232,62327806,61988102)Key Research Program of Frontier Sciences,CAS(ZDBS-LYJSC016)Guangdong Province Key Field RD Program Project(2020B0101110002)Science and Technology Planning Project of Guangdong Province(2019B090909011)Program of GBA Branch of AIRCAS(E0Z2D10600)。
文摘The photonic frequency-interleaving(PFI)technique has shown great potential for broadband signal acquisition,effectively overcoming the challenges of clock jitter and channel mismatch in the conventional time-interleaving paradigm.However,current comb-based PFI schemes have complex system architectures and face challenges in achieving large bandwidth,dense channelization,and flexible reconfigurability simultaneously,which impedes practical applications.In this work,we propose and demonstrate a broadband PFI scheme with high reconfigurability and scalability by exploiting multiple free-running lasers for dense spectral slicing with high crosstalk suppression.A dedicated system model is developed through a comprehensive analysis of the system non-idealities,and a cross-channel signal reconstruction algorithm is developed for distortion-free signal reconstruction,based on precise calibrations of intra-and inter-channel impairments.The system performance is validated through the reception of multi-format broadband signals,both digital and analog,with a detailed evaluation of signal reconstruction quality,achieving inter-channel phase differences of less than 2°.The reconfigurability and scalability of the scheme are demonstrated through a dual-band radar imaging experiment and a three-channel interleaving implementation with a maximum acquisition bandwidth of 4 GHz.To the best of our knowledge,this is the first demonstration of a practical radio-frequency(RF)application enabled by PFI.Our work provides an innovative solution for next-generation software-defined broadband RF receivers.
基金funded by the Deanship of Scientific Research and Libraries,Princess Nourah bint Abdulrahman University,through the Program of Research Project Funding After Publication,grant No.(RPFAP-82-1445)。
文摘This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raphson search rule(NRSR)to boost the exploration process,especially in search spaces with more local regions,and boost the exploitation with adaptive parameters alternating with random parameters in the original Puma.The effectiveness of the introduced IPuma is confirmed through comprehensive evaluations on the CEC’20 benchmark problems.It shows superior performance compared to both established and modern metaheuristic algorithms in terms of effectively navigating the search space and achieving convergence towards near-optimal regions.The findings indicated that the IPuma algorithm demonstrates considerable statistical promise and surpasses the performance of competing algorithms.In addition,the proposed IPuma is utilized to reconfigure a 9×9 PV array that operates under different shade patterns,such as lower triangular(LT),long wide(LW),and short wide(SW).In addition to other programmed approaches,such as the Whale optimization algorithm(WOA),grey wolf optimizer(GWO),Harris Hawks optimization(HHO),particle swarm optimization(PSO),gravitational search algorithm(GSA),biogeography-based optimization(BBO),sine cosine algorithm(SCA),equilibrium optimizer(EO),and original Puma,the indicated method is contrasted to the traditional configurations of TCT and Sudoku.In addition,the metrics of mismatch power loss,maximum efficiency improvement,efficiency improvement ratio,and peak-to-mean ratio are calculated to assess the effectiveness of the indicated approach.The proposed IPuma improved the generated power by 36.72%,28.03%,and 40.97%for SW,LW,and LT,respectively,outperforming the TCT configuration.In addition,it achieved the best maximum efficiency improvement among the algorithms considered,with 26.86%,21.89%,and 29.07%for the examined patterns.The results highlight the superiority and competence of the proposed approach in both convergence rates and stability,as well as applicability to dynamically reconfigure the PV system and enhance its harvested energy.
基金supported by the National Natural Science Foundation of China(General Program)under Grant 52571385National Key R&D Program of China(Grant No.2024YFC2815000 and No.2024YFB3816000)+12 种基金Open Fund of State Key Laboratory of Deep-sea Manned Vehicles(Grant No.2025SKLDMV07)Shenzhen Science and Technology Program(WDZC20231128114452001,JCYJ20240813112107010 and JCYJ20240813111910014)the Tsinghua SIGS Scientific Research Startup Fund(QD2022021C)the Dreams Foundation of Jianghuai Advance Technology Center(2023-ZM 01 Z006)the Ocean Decade International Cooperation Center(ODCC)(GHZZ3702840002024020000026)Shenzhen Key Laboratory of Advanced Technology for Marine Ecology(ZDSYS20230626091459009)Shenzhen Science and Technology Program(No.KJZD20240903100905008)the National Natural Science Foundation of China(No.22305141)Pearl River Talent Program(No.2023QN10C114)General Program of Guangdong Province(No.2025A1515011700)the Guangdong Innovative and Entrepreneurial Research Team Program(2023ZT10C040)Scientific Research Foundation from Shenzhen Finance Bureau(No.GJHZ20240218113600002)Tsinghua University(JC2023001).
文摘Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations remain in unit-level reconfiguration,multiaxial force and motion sensing,and robust operation across dynamically changing or irregular surfaces.Herein,we develop a reconfigurable omnidirectional triboelectric whisker sensor array(RO-TWSA)comprising multiple sensing units that integrate a triboelectric whisker structure(TWS)with an untethered hydro-sealing vacuum sucker(UHSVS),enabling reversibly portable deployment and omnidirectional perception across diverse surfaces.Using a simple dual-triangular electrode layout paired with MXene/silicone nanocomposite dielectric layer,the sensor unit achieves precise omnidirectional force and motion sensing with a detection threshold as low as 0.024 N and an angular resolution of 5°,while the UHSVS provides reliable and reversible multi-surface anchoring for the sensor units by involving a newly designed hydrogel combining high mechanical robustness and superior water absorption.Extensive experiments demonstrate the effectiveness of RO-TWSA across various interactive scenarios,including teleoperation,tactile diagnostics,and robotic autonomous exploration.Overall,RO-TWSA presents a versatile and high-resolution tactile interface,offering new avenues for intelligent perception and interaction in complex real-world environments.
基金Project(U2034211)supported by the National Natural Science Foundation of ChinaProject(20232ACE01013)supported by the Major Scientific and Technological Research and Development Special Project of Jiangxi Province,China。
文摘The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the uncertainties in train driving and operation,this paper analyzes the relationship between the safety of heavy-haul electric locomotive hauled trains and driving and operation.It studies the auxiliary intelligent driving safety operation control methods.Through K-means to identify the characteristics of drivers'driving manipulation,the hidden Markov model adaptively adjusts the train driving and operation sequence,and conducts auxiliary driving reconstruction for heavy-haul locomotive driving and operation.Based on the train running curve and the locomotive traction/braking characteristics,it smoothly controls the exertion of the traction/braking force of heavy-haul locomotives,thereby optimizing the driving safety control of heavy-haul trains in the vehicle-environment-track system.Finally,the train operation simulation and optimized driving verification are carried out by simulating some track sections.The results show that the proposed method can correct and pre-optimize driving operations,improving the smoothness of heavy-haul trains by approximately 10%.It verifies the effectiveness of the proposed train assisted driving control reconstruction method,facilitating the smooth and safe operation of heavy-haul trains.
基金supported by the National Natural Science Foundation of China(Grant Nos.32371796 and W2521030).
文摘Three-dimensional porous foams and aerogels with high compressibilityand elasticity hold great promise for applications in pressure sensing,electromagnetic interference(EMI)shielding,and thermal insulation.However,their widespread application is often hindered by compromised structural stabilityand inadequate fatigue resistance under repeated compression.Herein,asustainable“top-down”cell wall reconfiguration strategy is proposed to fabricatehighly elastic,fatigue-resistant,and electrically conductive lamellar wood spongefrom natural balsa wood.This strategy involves the conversion of the intrinsiccellular structure of wood into an arch-shaped lamellar architecture reinforcedby chemical cross-linking,followed by coating the lamellar scaffold with conductivepolypyrrole(PPy)via in situ polymerization.The resulting PPy-coatedcross-linked wood sponge(CWS@PPy)demonstrates reversible compressibility,excellent fatigue resistance(∼3.5%plastic deformation after 10,000 cyclesat 40%strain).The strain-induced conductivity changes in CWS@PPy enabletunable EMI shielding effectiveness under cyclic compression and also facilities high-sensitivity pressure sensing(0.72 kPa^(-1)).Additionally,CWS@PPy exhibits a low through-plane thermal conductivity of 0.037 W m^(-1)K^(-1),which can be dynamically tuned for adaptivethermal management.The proposed mechanically robust and conductive wood sponge provides a versatile and sustainable platform fornext-generation smart devices.
基金supported in part by the Fundamental Research Funds for the Central Universities under Grant 2242022k60004in part by the National Natural Science Foundation of China(NSFC)under Grants 62261160576,624B2036,W2421087,62422105+1 种基金in part by the Young Elite Scientists Sponsorship Program by CAST 2022QNRC001,and the“Zhishan”Scholars Programs of Southeast Universityin part by the Key Technologies R&D Program of Jiangsu(Prospective and Key Technologies for Industry)under Grants BE2023022,BE2023022-1 and BE2023022-2.
文摘Reconfigurable intelligent surfaces(RISs)not only assist communication but also help the localization of user equipment(UE).This study focuses on indoor localization of UE with a single access point(AP)and multiple RISs.First,we propose a two-stage channel estimation scheme where RIS phase shifts are tuned to obtain multiple channel soundings.In the first stage,the newtonized orthogonal matching pursuit algorithm extracts the parameters of multiple paths from the received signals.Then,the LOS path and RISreflected paths are identified.In the second stage,the estimated path gains of RIS-reflected paths with different phase shifts are utilized to determine the angle of arrival(AOA)at the RIS by obtaining the angular pseudo spectrum.Consequently,by taking the AP and RISs as reference points,the linear least squares estimator can locate UE with the estimated AOAs.Simulation results show that the proposed algorithm can realize centimeter-level localization accuracy in the discussed scenarios.Moreover,the higher accuracy of pseudo spectrum,a larger number of channel soundings,and a larger number of reference points can realize higher localization accuracy of UE.
基金supported by the National Natural Science Foundation of China(22168008,22378085)the Guangxi Natural Science Foundation(2024GXNSFDA010053)+1 种基金the Technology Development Project of Guangxi Bossco Environmental Protection Technology Co.,Ltd(202100039)Innovation Project of Guangxi Graduate Education(YCBZ2024065).
文摘Strategically coupling nanoparticle hybrids and internal thermosensitive molecular switches establishes an innovative paradigm for constructing micro/nanoscale-reconfigurable robots,facilitating energyefficient CO_(2) management in life-support systems of confined space.Here,a micro/nano-reconfigurable robot is constructed from the CO_(2) molecular hunters,temperature-sensitive molecular switch,solar photothermal conversion,and magnetically-driven function engines.The molecular hunters within the molecular extension state can capture 6.19 mmol g^(−1) of CO_(2) to form carbamic acid and ammonium bicarbonate.Interestingly,the molecular switch of the robot activates a molecular curling state that facilitates CO_(2) release through nano-reconfiguration,which is mediated by the temperature-sensitive curling of Pluronic F127 molecular chains during the photothermal desorption.Nano-reconfiguration of robot alters the amino microenvironment,including increasing surface electrostatic potential of the amino group and decreasing overall lowest unoccupied molecular orbital energy level.This weakened the nucleophilic attack ability of the amino group toward the adsorption product derivatives,thereby inhibiting the side reactions that generate hard-to-decompose urea structures,achieving the lowest regeneration temperature of 55℃ reported to date.The engine of the robot possesses non-contact magnetically-driven micro-reconfiguration capability to achieve efficient photothermal regeneration while avoiding local overheating.Notably,the robot successfully prolonged the survival time of mice in the sealed container by up to 54.61%,effectively addressing the issue of carbon suffocation in confined spaces.This work significantly enhances life-support systems for deep-space exploration,while stimulating innovations in sustainable carbon management technologies for terrestrial extreme environments.
基金supported by the Princess Nourah bint Abdulrahman University Researchers Supporting Project,number PNURSP2025R757Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘The integration of High-Altitude Platform Stations(HAPS)with Reconfigurable Intelligent Surfaces(RIS)represents a critical advancement for next-generation wireless networks,offering unprecedented opportunities for ubiquitous connectivity.However,existing research reveals significant gaps in dynamic resource allocation,joint optimization,and equitable service provisioning under varying channel conditions,limiting practical deployment of these technologies.This paper addresses these challenges by proposing a novel Fairness-Aware Deep Q-Learning(FAIRDQL)framework for joint resource management and phase configuration in HAPS-RIS systems.Our methodology employs a comprehensive three-tier algorithmic architecture integrating adaptive power control,priority-based user scheduling,and dynamic learning mechanisms.The FAIR-DQL approach utilizes advanced reinforcement learning with experience replay and fairness-aware reward functions to balance competing objectives while adapting to dynamic environments.Key findings demonstrate substantial improvements:9.15 dB SINR gain,12.5 bps/Hz capacity,78%power efficiency,and 0.82 fairness index.The framework achieves rapid 40-episode convergence with consistent delay performance.These contributions establish new benchmarks for fairness-aware resource allocation in aerial communications,enabling practical HAPS-RIS deployments in rural connectivity,emergency communications,and urban networks.
基金National Natural Science Foundation of China(Nos.61772130,71171045 and 61901104)Innovation Program of Shanghai Municipal Education Commission,China(No.14YZ130)。
文摘Vehicular communication systems rely on secure vehicle-to-vehicle(V2V)communications for safety-critical information exchange.However,the presence of eavesdropping vehicles poses a significant challenge.This paper investigates the security of V2V communications in reconfigurable intelligent surface(RIS)-assisted vehicular communication systems with spectrum sharing.It proposes a three-stage alternating optimization(TSAO)algorithm to address the complex problem of multiple eavesdropped V2V links that reuse the spectrum already occupied by vehicle-toinfrastructure(V2I)links.To solve the mixed-integer and non-convex optimization problem due to coupled variables and complex constraints,the algorithm decomposes the original problem into three easily solvable sub-problems:RIS reflection coefficient optimization,vehicle transmission power optimization,and spectrum sharing optimization.First,the RIS reflection coefficients are optimized by using the penalty convex-concave procedure(CCP)method.Second,the optimal power points are determined in the power optimization sub-problem.Finally,the spectrum sharing optimization sub-problem is constructed as a weighted bipartite graph matching problem and solved by using the optimal matching algorithm.The TSAO algorithm not only maximizes the sum V2V secrecy rate but also ensures the quality-of-service(QoS)requirements of the V2I links.Simulation results validate the superiority of the proposed algorithm and highlight the improvement in the sum V2V secrecy rate achieved by utilizing RIS technology in vehicular communication systems with spectrum sharing.
基金supported by the National Key R&D Program of China (Grant No.2023YFA1406400)the National Natural Science Foundation of China (Grant Nos.12534005 and 12325402)。
文摘Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of editable superconducting diodes could unlock transformative applications,including dynamically reconfigurable quantum circuits that adapt to operational requirements.Here,we report the first observation of the superconducting diode effect(SDE)in LaAlO_(3)/KTaO_(3) heterostructures—a two-dimensional oxide interface superconductor with exceptional tunability.We observe a strong SDE in Hall-bar(or strip-shaped)devices under perpendicular magnetic fields(<15 Oe),with efficiencies above 40%and rectification signals exceeding 10 mV.Through conductive atomic force microscope lithography,we demonstrate reversible nanoscale editing of the SDE’s polarity and efficiency by locally modifying the superconducting channel edges.This approach enables multiple nonvolatile configurations within a single device,realizing an editable superconducting diode.Our work establishes LaAlO_(3)/KTaO_(3) as a platform for vortex-based nonreciprocal transport and provides a pathway toward designer quantum circuits with on-demand functionalities.
基金supported by the National Natural Science Foundation of China(52422107,T2394471,and 62571319)Beijing Nova Program(20240484531)+1 种基金China Postdoctoral Science Foundation(2022M710074)and Open Research Fund Program of Beijing National Research Center for Information Science and Technology(04410304023).
文摘In the era of big data and artificial intelligence,optical neural networks(ONNs)have emerged as a promising alternative to conventional electronic approaches,offering superior parallelism,ultrafast processing speeds,and high energy efficiency[1-3].However,a major bottleneck in the practical implementation of ONNs is the absence of effective nonlinear activation functions.Self-driven photodetectors have emerged as versatile optical to electrical converters,opening innovative avenues for energy-effective and flexibly integrated activation functions in ONNs through their reconfigurable optoelectronic nonlinearity.
文摘Unmanned Aerial Vehicle(UAV)-aided communication,prized for its network reconfigurability,operational flexibility,and cost-effectiveness,is a key enabler of the low-altitude economy.However,the high possibilities of line-of-sight links and the broadcast nature of air-ground UAV communications make it vulnerable and prone to eavesdropping by malicious nodes.
基金supported by the National Natural Science Foundation of China(92164206,52261145694,T2394474,T2394470,623B2015,62271026,62401026,and 62404013)the National Key Research and Development Program of China(2022YFB4400200)+1 种基金the New Cornerstone Science Foundation through the XPLORER PRIZE,the National Postdoctoral Program for Innovative Talents(BX20220374 and BX20240455)the China Postdoctoral Science Foundation Funded Project(2023M740177 and 2022M720345).
文摘In recent years,physical unclonable function(PUF)has emerged as a lightweight solution in the Internet of Things security.However,conventional PUFs based on complementary metal oxide semiconductor(CMOS)present challenges such as insufficient randomness,significant power and area overhead,and vulnerability to environmental factors,leading to reduced reliability.In this study,we realize a strong,highly reliable and reconfigurable PUF with resistance against machine-learning attacks in a 1 kb spinorbit torque magnetic random access memory fabricated using a 180 nm CMOS process.This strong PUF achieves a challenge-response pair capacity of 10^(9) through a computing-in-memory approach.The results demonstrate that the proposed PUF exhibits near-ideal performance metrics:50.07% uniformity,50% diffuseness,49.89% uniqueness,and a bit error rate of 0%,even in a 375 K environment.The reconfigurability of PUF is demonstrated by a reconfigurable Hamming distance of 49.31% and a correlation coefficient of less than 0.2,making it difficult to extract output keys through side-channel analysis.Furthermore,resistance to machine-learning modeling attacks is confirmed by achieving an ideal accuracy prediction of approximately 50% in the test set.
基金the financial support from the National Key Research and Development Program of China(No.2023YFB3907001)the National Natural Science Foundation of China(Nos.U2233217,62371029)the UK Engineering and Physical Sciences Research Council(EPSRC),China(Nos.EP/M026981/1,EP/T021063/1 and EP/T024917/)。
文摘Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capabilities.The Uniform Circular Array(UCA)enables concurrent estimation of the Direction of Arrival(DOA)in both azimuth and elevation.Given the paramount importance of stability and real-time performance in interference localization,this work proposes an innovative approach to reduce the complexity and increase the robustness of the DOA estimation.The proposed method reduces computational complexity by selecting a reduced number of array elements to reconstruct a non-uniform sparse array from a UCA.To ensure DOA estimation accuracy,minimizing the Cramér-Rao Bound(CRB)is the objective,and the Spatial Correlation Coefficient(SCC)is incorporated as a constraint to mitigate side-lobe.The optimization model is a quadratic fractional model,which is solved by Semi-Definite Relaxation(SDR).When the array has perturbations,the mathematical expressions for CRB and SCC are re-derived to enhance the robustness of the reconstructed array.Simulation and hardware experiments validate the effectiveness of the proposed method in estimating interference DOA,showing high robustness and reductions in hardware and computational costs associated with DOA estimation.
基金the National Natural-Science Foundation of China(Grant No.62304137)Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2023A1515012479,2024A1515011737,and 2024A1515010006)+4 种基金the Science and Technology Innovation Commission of Shenzhen(Grant No.JCYJ20220818100206013)RSC Researcher Collaborations Grant(Grant No.C23-2422436283)State Key Laboratory of Radio Frequency Heterogeneous Integration(Independent Scientific Research Program No.2024010)the Project on Frontier and Interdisciplinary Research Assessment,Academic Divisions of the Chinese Academy of Sciences(Grant No.XK2023XXA002)NTUT-SZU Joint Research Program.
文摘In this data explosion era,ensuring the secure storage,access,and transmission of information is imperative,encom-passing all aspects ranging from safeguarding personal devices to formulating national information security strategies.Leverag-ing the potential offered by dual-type carriers for transportation and employing optical modulation techniques to develop high reconfigurable ambipolar optoelectronic transistors enables effective implementation of information destruction after read-ing,thereby guaranteeing data security.In this study,a reconfigurable ambipolar optoelectronic synaptic transistor based on poly(3-hexylthiophene)(P3HT)and poly[[N,N-bis(2-octyldodecyl)-napthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)](N2200)blend film was fabricated through solution-processed method.The resulting transistor exhib-ited a relatively large ON/OFF ratio of 10^(3) in both n-and p-type regions,and tunable photoconductivity after light illumination,particularly with green light.The photo-generated carriers could be effectively trapped under the gate bias,indicating its poten-tial application in mimicking synaptic behaviors.Furthermore,the synaptic plasticity,including volatile/non-volatile and excita-tory/inhibitory characteristics,could be finely modulated by electrical and optical stimuli.These optoelectronic reconfigurable properties enable the realization of information light assisted burn after reading.This study not only offers valuable insights for the advancement of high-performance ambipolar organic optoelectronic synaptic transistors but also presents innovative ideas for the future information security access systems.
基金supported by the National Natural Science Foundation of China(62202215)Liaoning Province Applied Basic Research Program(Youth Special Project,2023JH2/101600038)+2 种基金Shenyang Youth Science and Technology Innovation Talent Support Program(RC220458)Guangxuan Program of Shenyang Ligong University(SYLUGXRC202216)Basic Research Special Funds for Undergraduate Universities in Liaoning Province(LJ212410144067).
文摘The 6G smart Fog Radio Access Network(F-RAN)is an integration of 6G network intelligence technologies and the F-RAN architecture.Its aim is to provide low-latency and high-performance services for massive access devices.However,the performance of current 6G network intelligence technologies and its level of integration with the architecture,along with the system-level requirements for the number of access devices and limitations on energy consumption,have impeded further improvements in the 6G smart F-RAN.To better analyze the root causes of the network problems and promote the practical development of the network,this study used structured methods such as segmentation to conduct a review of the topic.The research results reveal that there are still many problems in the current 6G smart F-RAN.Future research directions and difficulties are also discussed.
基金supported in part by the National Natural Science Foundation of China under Grant 62071253,Grant 62371252 and Grant 62271268in part by the Jiangsu Provincial Key Research and Development Program under Grant BE2022800in part by the Jiangsu Provincial 333 Talent Project.
文摘In this paper,we examine an illegal wireless communication network consisting of an illegal user receiving illegal signals from an illegal station and propose an active reconfigurable intelligent surface(ARIS)-assisted multi-antenna jamming(MAJ)scheme denoted by ARIS-MAJ to interfere with the illegal signal transmission.In order to strike a balance between the jamming performance and the energy consumption,we consider a so-called jamming energy efficiency(JEE)which is defined as the ratio of achievable rate reduced by the jamming system to the corresponding power consumption.We formulate an optimization problem to maximize the JEE for the proposed ARIS-MAJ scheme by jointly optimizing the jammer’s beamforming vector and ARIS’s reflecting coefficients under the constraint that the jamming power received at the illegal user is lower than the illegal user’s detection threshold.To address the non-convex optimization problem,we propose the Dinkelbach-based alternating optimization(AO)algorithm by applying the semidefinite relaxation(SDR)algorithm with Gaussian randomization method.Numerical results validate that the proposed ARIS-MAJ scheme outperforms the passive reconfigurable intelligent surface(PRIS)-assisted multi-antenna jamming(PRIS-MAJ)scheme and the conventional multiantenna jamming scheme without RIS(NRIS-MAJ)in terms of the JEE.
