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
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
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
Position sensitive device(PSD)sensor is a vital optical element that is mainly used in tracking systems for visible light communication(VLC).Recently,a new reconfigurable PSD architecture emerged.The proposed architec...Position sensitive device(PSD)sensor is a vital optical element that is mainly used in tracking systems for visible light communication(VLC).Recently,a new reconfigurable PSD architecture emerged.The proposed architecture makes the PSD perform more functions by modifying its architecture.As the PSD is mainly formed of an array of photodiodes.The primary concept involves employing transistors to alternate between the operating modes of the photodiodes(photoconductive and photovoltaic).Additionally,alternating among output pins can be done based on the required function.This paper presents the mathematical modeling and simulation of a reconfigurable-multifunctional optical sensor which can perform energy harvesting and data acquisition,as well as positioning,which is not available in the traditional PSDs.Simulation using the MATLAB software tool was achieved to demonstrate the modeling.The simulation results confirmed the validity of the mathematical modeling and proved that the modified sensor architecture,as depicted by the equations,accurately describes its behavior.The proposed sensor is expected to extend the battery's lifecycle,reduce its physical size,and increase the integration and functionality of the system.The presented sensor might be used in free space optical(FSO)communication like cube satellites or even in underwater wireless optical communication(UWOC).展开更多
With the rapid development of holographic technology,metasurface-based holographic communication schemes have demonstrated immense potential for electromagnetic(EM)multifunctionality.However,traditional passive metasu...With the rapid development of holographic technology,metasurface-based holographic communication schemes have demonstrated immense potential for electromagnetic(EM)multifunctionality.However,traditional passive metasurfaces are severely limited by their lack of reconfigurability,hindering the realization of versatile holographic applications.Origami,an art form that mechanically induces spatial deformations,serves as a platform for multifunctional devices and has garnered significant attention in optics,physics,and materials science.The Miura-ori folding paradigm,characterized by its continuous reconfigurability in folded states,remains unexplored in the context of holographic imaging.Herein,we integrate the principles of Rosenfeld with L-and D-metal chiral enantiomers on a Miura-ori surface to tailor the aperture distribution.Leveraging the continuously tunable nature of the Miura-ori's folded states,the chiral response of the metallic structures varies across different folding configurations,enabling distinct EM holographic imaging functionalities.In the planar state,holographic encryption is achieved.Under specific folding conditions and driven by spin circularly polarized(CP)waves at a particular frequency,multiplexed holographic images can be reconstructed on designated focal planes with CP selectivity.Notably,the fabricated origami metasurface exhibits a large negative Poisson ratio,facilitating portability and deployment and offering novel avenues for spin-selective systems,camouflage,and information encryption.展开更多
In recent years,as the dimensions of the conventional semiconductor technology is approaching the physical limits,while the multifunction circuits are restricted by the relatively fixed characteristics of the traditio...In recent years,as the dimensions of the conventional semiconductor technology is approaching the physical limits,while the multifunction circuits are restricted by the relatively fixed characteristics of the traditional metal−oxide−semiconductor field-effect transistors,reconfigurable devices that can realize reconfigurable characteristics and multiple functions at device level have been seen as a promising method to improve integration density and reduce power consumption.Owing to the ultrathin structure,effective control of the electronic characteristics and ability to modulate structural defects,two-dimensional(2D)materials have been widely used to fabricate reconfigurable devices.In this review,we summarize the working principles and related logic applications of reconfigurable devices based on 2D materials,including generating tunable anti-ambipolar responses and demonstrating nonvolatile operations.Furthermore,we discuss the analog signal processing applications of anti-ambipolar transistors and the artificial intelligence hardware implementations based on reconfigurable transistors and memristors,respectively,therefore highlighting the outstanding advantages of reconfigurable devices in footprint,energy consumption and performance.Finally,we discuss the challenges of the 2D materials-based reconfigurable devices.展开更多
This article presents a compact crab-shaped reconfigurable antenna(CSRA)designed for 5G sub-6 GHz wireless applications. The antenna achieves enhanced gain in a miniaturized form factor by incorporating a hexagonal sp...This article presents a compact crab-shaped reconfigurable antenna(CSRA)designed for 5G sub-6 GHz wireless applications. The antenna achieves enhanced gain in a miniaturized form factor by incorporating a hexagonal split-ring structure controlled via two radio frequency(RF) positive-intrinsicnegative(PIN) diodes(BAR64-02V). While the antenna is primarily designed to operate at 3.50 GHz for sub-6 GHz 5G applications, RF switching enables the CSRA to cover a broader frequency spectrum, including the S-band, X-band, and portions of the Ku-band. The proposed antenna offers several advantages: It is low-cost(fabricated on an FR-4 substrate), compact(achieving 64.07% size reduction compared to conventional designs), and features both frequency and gain reconfigurability through digitally controlled PIN diode switching. The reflection coefficients of the antenna, both without diodes and across all four switching states, were experimentally validated in the laboratory using a Keysight Field Fox microwave analyzer(N9916A, 14 GHz). The simulated radiation patterns and gain characteristics closely matched the measured values, demonstrating an excellent agreement. This study bridges the gap between traditional and next-generation antenna designs by offering a compact,cost-effective, and high-performance solution for multiband, reconfigurable wireless communication systems. The integration of double-split-ring resonators and dynamic reconfigurability makes the proposed antenna a strong candidate for various applications, including S-band and X-band systems, as well as the emerging lower 6G band(7.125 GHz–8.400 GHz).展开更多
In this work,a flexible battery structure is fabricated using soft lithography and three-dimensional(3D) printing technology.Ga_(52.5)Sn_(39.5)Zn_(8) anode material,Bi_(67)In_(33) cathode material,and alkaline hydroge...In this work,a flexible battery structure is fabricated using soft lithography and three-dimensional(3D) printing technology.Ga_(52.5)Sn_(39.5)Zn_(8) anode material,Bi_(67)In_(33) cathode material,and alkaline hydrogel electrolyte are introduced to form the flexible battery.A variety of circuit structures are fabricated to realize the series-parallel integration of different numbers of single cells and achieve the fabrication of batteries with different voltages and powers,with a maximum open-circuit voltage(OCV) of 4.6 V and a maximum output power of 1.193 mW.A reconfigurable soft battery group is proposed,and the regulation of the battery voltage has been realized through the microfluidic perfusion process without the need for an external variable-voltage circuit.We have also fabricated an EGaIn-NaOH microfluidic switch to achieve the control of the light emitting diode(LED).In addition,a wristband with a flexible battery is demonstrated to realize power supply to a liquid crystal display(LCD) with a clock or a temperature sensor.展开更多
Cable-driven parallel robots(CDPRs)have advantages of larger workspace and load capacity than conventional parallel robots while existing interference problems among cables,workpieces and the end-effector.In order to ...Cable-driven parallel robots(CDPRs)have advantages of larger workspace and load capacity than conventional parallel robots while existing interference problems among cables,workpieces and the end-effector.In order to avoid collision and improve the flexibility of the robots,this study proposes a reconfigurable cable-driven parallel robot(RCDPR)having characteristics of large load-to-weight ratio,easy modularity and variable stiffness.Adjustable brackets are connected to the moving platform to adjust the position of the pull-out point with the movement of the end-effector.In addition,a variable stiffness actuator(VSA)accompanied by finite element analysis is designed to optimize the cable tension to adapt different task requirements.Firstly,a new idea of reconfiguration is given,and an inverse kinematic model is established using the vector closure principle to derive its inverse kinematic expressions focusing on one of the configurations.Second,the VSA is attached to each cable to achieve stiffness adjustment,and the system stiffness is derived in detail.Finally,the rationality and accuracy of the robot are verified through numerical analysis,providing a reference for subsequent trajectory planning with implications.展开更多
With the growing demand for compute-intensive applications such as artificial intelligence(AI)and video processing,traditional reconfigurable array processors fail to meet the requirements of high-performance computin...With the growing demand for compute-intensive applications such as artificial intelligence(AI)and video processing,traditional reconfigurable array processors fail to meet the requirements of high-performance computing and related domains,primarily due to their high power consumption and low energy efficiency.To address this limitation,this paper proposes an accuracy-adaptive approxi-mate reconfigurable array architecture featuring preset dual thresholds and support for four computa-tional accuracy levels,enabling flexible adaptation to diverse application needs.The architecture in-tegrates a self-adaptive mechanism that dynamically adjusts computational precision based on real-time error threshold feedback.To evaluate the proposed architecture,the you only look once version 5(YOLOv5)deep neural network algorithm is parallelized and deployed on the approximate recon-figurable array.Experimental results demonstrate that the architecture achieves an 18.93%reduc-tion in power consumption compared with conventional reconfigurable structures operating in full-pre-cision mode.Additionally,the design exhibits superior energy efficiency and reduced computational resource utilization,thereby significantly enhancing the overall performance and applicability of reconfigurable array processors in power-sensitive scenarios.展开更多
Dear Editor,As the Internet of things(IoT)and autonomous driving continue to evolve,positioning technology faces increasing demands for higher accuracy and reliability.Traditional positioning methods often struggle in...Dear Editor,As the Internet of things(IoT)and autonomous driving continue to evolve,positioning technology faces increasing demands for higher accuracy and reliability.Traditional positioning methods often struggle in complex signal environments with multipath interference and non-line-of-sight(NLOS)conditions.Reconfigurable intelligent surfaces(RIS),an innovative technology that can flexibly control signal propagation,offer new possibilities for positioning systems.展开更多
When deploying Reconfigurable Intelligent Surface(RIS)to improve System Sum-Rate(SSR),the timeliness and accuracy of SSR optimization methods are difficult to achieve simultaneously through a single algorithm.Some alg...When deploying Reconfigurable Intelligent Surface(RIS)to improve System Sum-Rate(SSR),the timeliness and accuracy of SSR optimization methods are difficult to achieve simultaneously through a single algorithm.Some algorithms focus on timeliness,while some focus on accuracy.In this paper,in order to take into account the timeliness and accuracy of the system comprehensively,we construct SSR analysis model of RIS-assisted multiuser downlink communication system and propose several new optimization methods.The goal is to maximize SSR by using the proposed algorithms to jointly optimize power allocation and reflection coefficients.To solve this comprehensive problem,two sets of Alternating Optimization(AO)-based timeliness algorithms and one set of Monotonic Optimization(MO)-based accuracy algorithms are proposed separately to jointly optimize system performance.First,the Water-Filling(WF)-based and penalty-based low complexity algorithms are developed to optimize power allocation and reflection coefficients respectively.To improve the reality of the calculation,penalty-based algorithm cleverly considers residual noise that is difficult to calculate.Then,for further improve the timeliness,a new Successive Convex Approximation(SCA)-based low complexity algorithm is designed to further optimize reflection coefficients and its convergence is proved.Third,in order to verify the effectiveness of the proposed timeliness algorithms,we further propose MO-based accuracy algorithms,in which,the Polyblock Outer Approximation(POA)algorithm,the Semidefinite Relaxation(SDR)method,and the bisection search algorithm are combined in a novel way.Numerical results confirm the timeliness of AO-based algorithms and the accuracy of MO-based algorithms.They supervise and complement each other.展开更多
Current research on reconfigurable parallel mechanisms(RPMs)primarily focuses on achieving limited configuration changes,while mechanisms capable of extensive mode switching with distinct motion branches remain challe...Current research on reconfigurable parallel mechanisms(RPMs)primarily focuses on achieving limited configuration changes,while mechanisms capable of extensive mode switching with distinct motion branches remain challenging to design.Conventional kinematotropic chains offer limited reconfigurability,underscoring the need for novel designs that enable broader operational adaptability.In this research,a novel diamond-like chain(DLC)with metamorphic units is proposed developed from generalized diamond kinematotropic chains.By altering the axes of the metamorphic units,the DLC realizes three distinct configurations,each corresponding to one of five motion branches characterized by bifurcation and metamorphic transitions.This DLC serves as the fundamental building block for constructing a reconfigurable hybrid limb.Using screw theory,the constraint properties of the limb in its five phases are analyzed and classified into three types:unconstrained limbs,limbs applying constraint forces,and limbs applying constraint couples.Based on this analysis,a RPM consisting of three reconfigurable limbs is developed.Its reconfigurability stems from the inherent bifurcation and metamorphic capabilities of the DLC-based limbs.This research introduces a RPM capable of controlled switching among ten distinct motion modes,with mobility ranging from three to six degrees of freedom.The proposed mechanism demonstrates high versatility and practical feasibility,offering a promising solution for applications requiring variable motion characteristics and adaptive performance.展开更多
A polarization converter with broadband polarization characteristics and capable of dynamic reconfiguration is proposed.By introducing out-of-plane degrees of freedom,dynamically tunable broadband and high-efficiency ...A polarization converter with broadband polarization characteristics and capable of dynamic reconfiguration is proposed.By introducing out-of-plane degrees of freedom,dynamically tunable broadband and high-efficiency linear polarization conversion within the wavelength range of 2000-2800 nm is achieved.Research results indicate that when a two-dimensional(2D)split-ring resonator(SRR)is irradiated by a low-dose focused ion beam,it will deform upward and transform into a three-dimensional(3D)SRR,achieving a linear polarization conversion efficiency of over 90%.The 3D SRR can be driven by electrostatic force to return to the 2D SRR state,thereby realizing the dynamic reconfiguration of this polarization converter.By changing the applied voltage and adjusting the structural parameters,a tailored polarization converter that exhibits broadband performance and high polarization conversion efficiency is also achieved.The results may provide novel ideas and technical methodologies for various applications such as polarized optical imaging,emerging display technologies,polarized optical communication,and optical sensing.展开更多
Progressing beyond the stowage and deployment of reflectors and designing for multiple deployed states result in reflector shape reconfiguration,thus allowing for new functions including radiation pattern reconfigurat...Progressing beyond the stowage and deployment of reflectors and designing for multiple deployed states result in reflector shape reconfiguration,thus allowing for new functions including radiation pattern reconfiguration,and is valuable for space applications such as satellite-based radar and communications.This paper introduces a concept for achieving the deployment and shape reconfiguration of a paraboloid reflector using a 7R-8R(revolute joint)truss network.By realizing reconfigurability mechanically,complex electronic systems such as phased arrays can be avoided,and adopting a single-degree-of-freedom(DOF)design further reduces the number of required actuators.The proposed reflector is axisymmetric and can be doubly curved.It comprises a flexible mesh surface supported by a rigid truss network constructed from 7R and 8R linkages.Approximation of multiple target surfaces is achieved by synthesizing the truss network dimensions using a multiobjective optimization approach.The non-dominated sorting genetic algorithm is used in conjunction with analytical dimension parameterization and forward kinematics computation to determine the optimal dimensions for the truss network.In the resulting designs,the reflector follows a single-DOF trajectory,on which it unfolds from a compact stowed bundle toward a deployed state approximating a doubly curved target surface,then onwards to additional deployed states approximating different target surfaces.Design studies are conducted to demonstrate the reflector’s ability to approximate different target surfaces and continuously transform between such surfaces.This study proposes a new method for reconfiguring reflector shape mechanically,thus uniquely reconfiguring the shape of a doubly curved surface and achieving both deployment and shape reconfiguration under a unified single-DOF motion.展开更多
Planar lightwave circuit(PLC)splitters have long been foundational components in passive optical communication networks,achieving commercial success since the 1990s.However,their inherent fixed splitting ratios impose...Planar lightwave circuit(PLC)splitters have long been foundational components in passive optical communication networks,achieving commercial success since the 1990s.However,their inherent fixed splitting ratios impose significant limitations on capacity expansion,often requiring physical replacement and causing service disruptions.Thermally tunable optical splitters address this challenge by enabling adjustable splitting ratios,but their operation is contingent upon a continuous power supply and complex driving systems.In this work,we present a novel,non-volatile tunable PLC platform based on Sb_(2)S_(3)phase-change materials.The proposed device,which incor-porates a Mach-Zehnder interferometer(MZI)optical switch structure,offers tunable splitting ratios via laser-direct writing or ohmic heating,providing flexible reconfiguration capabilities.Experimental results demonstrate non-volatile power splitting ranging from 50∶50 to 20∶80,with a modest increase of approximately 1 dB in additional loss.This work highlights the potential of the proposed platform for low-power,high-efficiency,and reconfigurable photonic networks.展开更多
Dual-output power amplifiers(PAs)have shown great potential in the area of radar,satellite and wireless communication systems.However,the flexibility of the power allocation in a dual-output PA without sacrificing eff...Dual-output power amplifiers(PAs)have shown great potential in the area of radar,satellite and wireless communication systems.However,the flexibility of the power allocation in a dual-output PA without sacrificing efficiency and circuit complexity still needs further investigation.This paper presents a digitally dual-input dual-output(DIDO)PA with reconfigurable modes for power allocation application.The proposed DIDO PA is consist of two identical sub-amplifiers and a 90◦coupler,showing a simple circuit topology.The input amplitudes of the two sub-amplifiers and their phase difference is dynamically controlled leveraging on the dual-input technique,leading to reconfigurable operation modes from power allocation to Doherty.In the power allocation mode,flexible power allocation between two output ports can be obtained by the DIDO PA without sacrificing drain efficiency(DE).On the other hand,flexible power transferring and enhanced back-off DE can be simultaneously achieved by the DIDO PA when it is in the Doherty mode.As a proof of concept,a DIDO PA operating at 2.4 GHz is fabricated and measured in this paper.In the power allocation mode,the DIDO PA achieves a DE of more than 71.8%with a total output power of larger than 44 dBm.Moreover,when the DIDO PA operates in the Doherty mode,it could deliver a maximum output power of more than 44 dBm with a saturation DE of more than 73.9%and a 6 dB back-off DE of more than 61.2%.展开更多
With digital coding technology,reconfigurable intelligent surfaces(RISs)become powerful real-time sys-tems for manipulating electromagnetic(EM)waves.However,most automatic RIS designs involve exten-sive numerical simu...With digital coding technology,reconfigurable intelligent surfaces(RISs)become powerful real-time sys-tems for manipulating electromagnetic(EM)waves.However,most automatic RIS designs involve exten-sive numerical simulations of the unit,including the passive pattern and active devices,requiring high data acquisition and training costs.In addition,for passive patterns,the widely employed random pixe-lated method presents design efficiency and effectiveness challenges due to the massive pixel combina-tions and blocked excitation current flow in discrete patterns.To overcome these two critical problems,we propose a versatile RIS design paradigm with efficient topology representation and a separate design architecture.First,a non-uniform rational B-spline(NURBS)is introduced to represent continuous pat-terns and solve excitation current flow issues.This representation makes it possible to finely tune con-tinuous patterns with several control points,greatly reducing the pattern solution space by 20-fold and facilitating RIS optimization.Then,employing multiport network theory to separate the passive pat-tern and active device from the unit,the separate design architecture significantly reduces the dataset acquisition cost by 62.5%.Through multistep multiport calculation,the multistate EM responses of the RIS under different structural combinations can be quickly obtained with only one prediction of pattern response,thereby achieving dataset and model reuse for different RIS designs.With a hybrid continuous-discrete optimization algorithm,three examples—including two typical high-performance RISs and an ultra-wideband multilayer RIS—are provided to validate the superiority of our paradigm.Our work offers an efficient solution for RIS automatic design,and the resulting structure is expected to boost RIS appli-cations in the fields of wireless communication and sensing.展开更多
Reconfigurable intelligent surface(RIS)is a promising candidate technology of the upcoming Sixth Generation(6G)communication system for its ability to provide unprecedented spectral and energy efficiency increment thr...Reconfigurable intelligent surface(RIS)is a promising candidate technology of the upcoming Sixth Generation(6G)communication system for its ability to provide unprecedented spectral and energy efficiency increment through passive beamforming.However,it is challenging to obtain instantaneous channel state information(I-CSI)for RIS,which obliges us to use statistical channel state information(S-CSI)to achieve passive beamforming.In this paper,RIS-aided multiple-input single-output(MISO)multi-user downlink communication system with correlated channels is investigated.Then,we formulate the problem of joint beamforming design at the AP and RIS to maximize the sum ergodic spectral efficiency(ESE)of all users to improve the network capacity.Since it is too hard to compute sum ESE,an ESE approximation is adopted to reformulate the problem into a more tractable form.Then,we present two joint beamforming algorithms,namely the singular value decomposition-gradient descent(SVD-GD)algorithm and the fractional programming-gradient descent(FP-GD)algorithm.Simulation results show the effectiveness of our proposed algorithms and validate that 2-bits quantizer is enough for RIS phase shifts implementation.展开更多
Reconfigurable intelligent surface(RIS)has proven to be promising for future wireless communication.Due to its ability to manipulate electromagnetic(EM)waves,RIS provides a flexible and programmable way to implement i...Reconfigurable intelligent surface(RIS)has proven to be promising for future wireless communication.Due to its ability to manipulate electromagnetic(EM)waves,RIS provides a flexible and programmable way to implement intelligent wireless environments.While path loss modeling has been conducted in some prior research,an issue remaining unknown is the characteristics of multi-beam path loss for RIS.In this paper,we model,simulate and measure the multi-beam path loss in RIS-assisted broadcast communication scenarios.We propose two specific configurations of RIS and derive the path loss models,which reveal that the incident beam can be equally divided into multiple beams without power loss through rational design of the phase coding.The proposed path loss model is validated through simulation subsequently.To further verify our conclusions,we build a millimeter wave(mmWave)measurement system with a 35 GHz fabricated RIS.The measurement result corresponds well with the simulation,which shows a difference of about 3 dB in the received signal power of quad-beam compared with dual-beam,as well as dual-beam compared with single-beam,except for the impact of radiation patterns of the antennas and RIS elements.展开更多
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 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.
文摘Position sensitive device(PSD)sensor is a vital optical element that is mainly used in tracking systems for visible light communication(VLC).Recently,a new reconfigurable PSD architecture emerged.The proposed architecture makes the PSD perform more functions by modifying its architecture.As the PSD is mainly formed of an array of photodiodes.The primary concept involves employing transistors to alternate between the operating modes of the photodiodes(photoconductive and photovoltaic).Additionally,alternating among output pins can be done based on the required function.This paper presents the mathematical modeling and simulation of a reconfigurable-multifunctional optical sensor which can perform energy harvesting and data acquisition,as well as positioning,which is not available in the traditional PSDs.Simulation using the MATLAB software tool was achieved to demonstrate the modeling.The simulation results confirmed the validity of the mathematical modeling and proved that the modified sensor architecture,as depicted by the equations,accurately describes its behavior.The proposed sensor is expected to extend the battery's lifecycle,reduce its physical size,and increase the integration and functionality of the system.The presented sensor might be used in free space optical(FSO)communication like cube satellites or even in underwater wireless optical communication(UWOC).
基金financial supports from National Key Research and Development Program of China(No.2022YFB3806200)。
文摘With the rapid development of holographic technology,metasurface-based holographic communication schemes have demonstrated immense potential for electromagnetic(EM)multifunctionality.However,traditional passive metasurfaces are severely limited by their lack of reconfigurability,hindering the realization of versatile holographic applications.Origami,an art form that mechanically induces spatial deformations,serves as a platform for multifunctional devices and has garnered significant attention in optics,physics,and materials science.The Miura-ori folding paradigm,characterized by its continuous reconfigurability in folded states,remains unexplored in the context of holographic imaging.Herein,we integrate the principles of Rosenfeld with L-and D-metal chiral enantiomers on a Miura-ori surface to tailor the aperture distribution.Leveraging the continuously tunable nature of the Miura-ori's folded states,the chiral response of the metallic structures varies across different folding configurations,enabling distinct EM holographic imaging functionalities.In the planar state,holographic encryption is achieved.Under specific folding conditions and driven by spin circularly polarized(CP)waves at a particular frequency,multiplexed holographic images can be reconstructed on designated focal planes with CP selectivity.Notably,the fabricated origami metasurface exhibits a large negative Poisson ratio,facilitating portability and deployment and offering novel avenues for spin-selective systems,camouflage,and information encryption.
基金support from the National Key Research and Development Program of China(Grant nos.2024YFA1409700 and 2023YFA1407000)the National Natural Science Foundation of China(Grant no.62374158).
文摘In recent years,as the dimensions of the conventional semiconductor technology is approaching the physical limits,while the multifunction circuits are restricted by the relatively fixed characteristics of the traditional metal−oxide−semiconductor field-effect transistors,reconfigurable devices that can realize reconfigurable characteristics and multiple functions at device level have been seen as a promising method to improve integration density and reduce power consumption.Owing to the ultrathin structure,effective control of the electronic characteristics and ability to modulate structural defects,two-dimensional(2D)materials have been widely used to fabricate reconfigurable devices.In this review,we summarize the working principles and related logic applications of reconfigurable devices based on 2D materials,including generating tunable anti-ambipolar responses and demonstrating nonvolatile operations.Furthermore,we discuss the analog signal processing applications of anti-ambipolar transistors and the artificial intelligence hardware implementations based on reconfigurable transistors and memristors,respectively,therefore highlighting the outstanding advantages of reconfigurable devices in footprint,energy consumption and performance.Finally,we discuss the challenges of the 2D materials-based reconfigurable devices.
文摘This article presents a compact crab-shaped reconfigurable antenna(CSRA)designed for 5G sub-6 GHz wireless applications. The antenna achieves enhanced gain in a miniaturized form factor by incorporating a hexagonal split-ring structure controlled via two radio frequency(RF) positive-intrinsicnegative(PIN) diodes(BAR64-02V). While the antenna is primarily designed to operate at 3.50 GHz for sub-6 GHz 5G applications, RF switching enables the CSRA to cover a broader frequency spectrum, including the S-band, X-band, and portions of the Ku-band. The proposed antenna offers several advantages: It is low-cost(fabricated on an FR-4 substrate), compact(achieving 64.07% size reduction compared to conventional designs), and features both frequency and gain reconfigurability through digitally controlled PIN diode switching. The reflection coefficients of the antenna, both without diodes and across all four switching states, were experimentally validated in the laboratory using a Keysight Field Fox microwave analyzer(N9916A, 14 GHz). The simulated radiation patterns and gain characteristics closely matched the measured values, demonstrating an excellent agreement. This study bridges the gap between traditional and next-generation antenna designs by offering a compact,cost-effective, and high-performance solution for multiband, reconfigurable wireless communication systems. The integration of double-split-ring resonators and dynamic reconfigurability makes the proposed antenna a strong candidate for various applications, including S-band and X-band systems, as well as the emerging lower 6G band(7.125 GHz–8.400 GHz).
基金supported by the Science and Technology Program from State Grid Corporation of China through the Development of Flexible Liquid Metal Based Micro-Sensor with Anti-Electromagnetic Interference Ability for Power Engineering Applications under Grant 5700-202155453A-00-00。
文摘In this work,a flexible battery structure is fabricated using soft lithography and three-dimensional(3D) printing technology.Ga_(52.5)Sn_(39.5)Zn_(8) anode material,Bi_(67)In_(33) cathode material,and alkaline hydrogel electrolyte are introduced to form the flexible battery.A variety of circuit structures are fabricated to realize the series-parallel integration of different numbers of single cells and achieve the fabrication of batteries with different voltages and powers,with a maximum open-circuit voltage(OCV) of 4.6 V and a maximum output power of 1.193 mW.A reconfigurable soft battery group is proposed,and the regulation of the battery voltage has been realized through the microfluidic perfusion process without the need for an external variable-voltage circuit.We have also fabricated an EGaIn-NaOH microfluidic switch to achieve the control of the light emitting diode(LED).In addition,a wristband with a flexible battery is demonstrated to realize power supply to a liquid crystal display(LCD) with a clock or a temperature sensor.
基金Supported by National Natural Science Foundation of China(Grant Nos.52335002,52205014,52275033)the Fundamental Research Funds for the Central Universities(Grant No.JZ2024HGTB0245).
文摘Cable-driven parallel robots(CDPRs)have advantages of larger workspace and load capacity than conventional parallel robots while existing interference problems among cables,workpieces and the end-effector.In order to avoid collision and improve the flexibility of the robots,this study proposes a reconfigurable cable-driven parallel robot(RCDPR)having characteristics of large load-to-weight ratio,easy modularity and variable stiffness.Adjustable brackets are connected to the moving platform to adjust the position of the pull-out point with the movement of the end-effector.In addition,a variable stiffness actuator(VSA)accompanied by finite element analysis is designed to optimize the cable tension to adapt different task requirements.Firstly,a new idea of reconfiguration is given,and an inverse kinematic model is established using the vector closure principle to derive its inverse kinematic expressions focusing on one of the configurations.Second,the VSA is attached to each cable to achieve stiffness adjustment,and the system stiffness is derived in detail.Finally,the rationality and accuracy of the robot are verified through numerical analysis,providing a reference for subsequent trajectory planning with implications.
基金Supported by the National Science and Technology Major Project(No.2022ZD0119001)the National Natural Science Foundation of China(No.61834005,61802304)the Key R&D Program Projects in Shaanxi Province(No.2024GX-YBXM-100).
文摘With the growing demand for compute-intensive applications such as artificial intelligence(AI)and video processing,traditional reconfigurable array processors fail to meet the requirements of high-performance computing and related domains,primarily due to their high power consumption and low energy efficiency.To address this limitation,this paper proposes an accuracy-adaptive approxi-mate reconfigurable array architecture featuring preset dual thresholds and support for four computa-tional accuracy levels,enabling flexible adaptation to diverse application needs.The architecture in-tegrates a self-adaptive mechanism that dynamically adjusts computational precision based on real-time error threshold feedback.To evaluate the proposed architecture,the you only look once version 5(YOLOv5)deep neural network algorithm is parallelized and deployed on the approximate recon-figurable array.Experimental results demonstrate that the architecture achieves an 18.93%reduc-tion in power consumption compared with conventional reconfigurable structures operating in full-pre-cision mode.Additionally,the design exhibits superior energy efficiency and reduced computational resource utilization,thereby significantly enhancing the overall performance and applicability of reconfigurable array processors in power-sensitive scenarios.
基金supported by the Open Fund Project of Key Laboratory of Ocean Observation Technology,MNR(2023klootA01).
文摘Dear Editor,As the Internet of things(IoT)and autonomous driving continue to evolve,positioning technology faces increasing demands for higher accuracy and reliability.Traditional positioning methods often struggle in complex signal environments with multipath interference and non-line-of-sight(NLOS)conditions.Reconfigurable intelligent surfaces(RIS),an innovative technology that can flexibly control signal propagation,offer new possibilities for positioning systems.
基金supported in part by Natural Science Foundation of China(92367102)in part by National Science and Technology Major Project(2024ZD1300400).
文摘When deploying Reconfigurable Intelligent Surface(RIS)to improve System Sum-Rate(SSR),the timeliness and accuracy of SSR optimization methods are difficult to achieve simultaneously through a single algorithm.Some algorithms focus on timeliness,while some focus on accuracy.In this paper,in order to take into account the timeliness and accuracy of the system comprehensively,we construct SSR analysis model of RIS-assisted multiuser downlink communication system and propose several new optimization methods.The goal is to maximize SSR by using the proposed algorithms to jointly optimize power allocation and reflection coefficients.To solve this comprehensive problem,two sets of Alternating Optimization(AO)-based timeliness algorithms and one set of Monotonic Optimization(MO)-based accuracy algorithms are proposed separately to jointly optimize system performance.First,the Water-Filling(WF)-based and penalty-based low complexity algorithms are developed to optimize power allocation and reflection coefficients respectively.To improve the reality of the calculation,penalty-based algorithm cleverly considers residual noise that is difficult to calculate.Then,for further improve the timeliness,a new Successive Convex Approximation(SCA)-based low complexity algorithm is designed to further optimize reflection coefficients and its convergence is proved.Third,in order to verify the effectiveness of the proposed timeliness algorithms,we further propose MO-based accuracy algorithms,in which,the Polyblock Outer Approximation(POA)algorithm,the Semidefinite Relaxation(SDR)method,and the bisection search algorithm are combined in a novel way.Numerical results confirm the timeliness of AO-based algorithms and the accuracy of MO-based algorithms.They supervise and complement each other.
基金Supported by National Natural Science Foundation of China(Grant No.52175019)Beijing Municipal Natural Science Foundation(Grant Nos.L222038,20240484699)+1 种基金Joint Funds of Industry-university-research of Shanghai Academy of Spaceflight Technology(Grant No.SAST2022-017)Beijing Municipal Key Laboratory of Space-ground Interconnection and Convergence of China and Key Laboratory of IoT Monitoring and Early Warning,Ministry of Emergency Management,Project‘Vice President of Science and Technology’of Changping District,Beijing.
文摘Current research on reconfigurable parallel mechanisms(RPMs)primarily focuses on achieving limited configuration changes,while mechanisms capable of extensive mode switching with distinct motion branches remain challenging to design.Conventional kinematotropic chains offer limited reconfigurability,underscoring the need for novel designs that enable broader operational adaptability.In this research,a novel diamond-like chain(DLC)with metamorphic units is proposed developed from generalized diamond kinematotropic chains.By altering the axes of the metamorphic units,the DLC realizes three distinct configurations,each corresponding to one of five motion branches characterized by bifurcation and metamorphic transitions.This DLC serves as the fundamental building block for constructing a reconfigurable hybrid limb.Using screw theory,the constraint properties of the limb in its five phases are analyzed and classified into three types:unconstrained limbs,limbs applying constraint forces,and limbs applying constraint couples.Based on this analysis,a RPM consisting of three reconfigurable limbs is developed.Its reconfigurability stems from the inherent bifurcation and metamorphic capabilities of the DLC-based limbs.This research introduces a RPM capable of controlled switching among ten distinct motion modes,with mobility ranging from three to six degrees of freedom.The proposed mechanism demonstrates high versatility and practical feasibility,offering a promising solution for applications requiring variable motion characteristics and adaptive performance.
基金supported by the National Natural Science Foundation of China(Nos.T2325005,62375016,62475250)the Science and Technology Project of Guangdong(No.2020B010190001)。
文摘A polarization converter with broadband polarization characteristics and capable of dynamic reconfiguration is proposed.By introducing out-of-plane degrees of freedom,dynamically tunable broadband and high-efficiency linear polarization conversion within the wavelength range of 2000-2800 nm is achieved.Research results indicate that when a two-dimensional(2D)split-ring resonator(SRR)is irradiated by a low-dose focused ion beam,it will deform upward and transform into a three-dimensional(3D)SRR,achieving a linear polarization conversion efficiency of over 90%.The 3D SRR can be driven by electrostatic force to return to the 2D SRR state,thereby realizing the dynamic reconfiguration of this polarization converter.By changing the applied voltage and adjusting the structural parameters,a tailored polarization converter that exhibits broadband performance and high polarization conversion efficiency is also achieved.The results may provide novel ideas and technical methodologies for various applications such as polarized optical imaging,emerging display technologies,polarized optical communication,and optical sensing.
基金Supported by National Natural Science Foundation of China(Grant Nos.52320105005,52035008)the New Cornerstone Science Foundation through the Xplorer Prize(Grant No.XPLORER-2020-1035).
文摘Progressing beyond the stowage and deployment of reflectors and designing for multiple deployed states result in reflector shape reconfiguration,thus allowing for new functions including radiation pattern reconfiguration,and is valuable for space applications such as satellite-based radar and communications.This paper introduces a concept for achieving the deployment and shape reconfiguration of a paraboloid reflector using a 7R-8R(revolute joint)truss network.By realizing reconfigurability mechanically,complex electronic systems such as phased arrays can be avoided,and adopting a single-degree-of-freedom(DOF)design further reduces the number of required actuators.The proposed reflector is axisymmetric and can be doubly curved.It comprises a flexible mesh surface supported by a rigid truss network constructed from 7R and 8R linkages.Approximation of multiple target surfaces is achieved by synthesizing the truss network dimensions using a multiobjective optimization approach.The non-dominated sorting genetic algorithm is used in conjunction with analytical dimension parameterization and forward kinematics computation to determine the optimal dimensions for the truss network.In the resulting designs,the reflector follows a single-DOF trajectory,on which it unfolds from a compact stowed bundle toward a deployed state approximating a doubly curved target surface,then onwards to additional deployed states approximating different target surfaces.Design studies are conducted to demonstrate the reflector’s ability to approximate different target surfaces and continuously transform between such surfaces.This study proposes a new method for reconfiguring reflector shape mechanically,thus uniquely reconfiguring the shape of a doubly curved surface and achieving both deployment and shape reconfiguration under a unified single-DOF motion.
基金sponsored by the National Key Research and Development Program of China(2020YFA0714504,2019YFA0709100)the program of the National Natural Science Foundation of China(U24A20309,62305043).
文摘Planar lightwave circuit(PLC)splitters have long been foundational components in passive optical communication networks,achieving commercial success since the 1990s.However,their inherent fixed splitting ratios impose significant limitations on capacity expansion,often requiring physical replacement and causing service disruptions.Thermally tunable optical splitters address this challenge by enabling adjustable splitting ratios,but their operation is contingent upon a continuous power supply and complex driving systems.In this work,we present a novel,non-volatile tunable PLC platform based on Sb_(2)S_(3)phase-change materials.The proposed device,which incor-porates a Mach-Zehnder interferometer(MZI)optical switch structure,offers tunable splitting ratios via laser-direct writing or ohmic heating,providing flexible reconfiguration capabilities.Experimental results demonstrate non-volatile power splitting ranging from 50∶50 to 20∶80,with a modest increase of approximately 1 dB in additional loss.This work highlights the potential of the proposed platform for low-power,high-efficiency,and reconfigurable photonic networks.
基金supported in part by the National Natural Science Foundation of China(No.62201100).
文摘Dual-output power amplifiers(PAs)have shown great potential in the area of radar,satellite and wireless communication systems.However,the flexibility of the power allocation in a dual-output PA without sacrificing efficiency and circuit complexity still needs further investigation.This paper presents a digitally dual-input dual-output(DIDO)PA with reconfigurable modes for power allocation application.The proposed DIDO PA is consist of two identical sub-amplifiers and a 90◦coupler,showing a simple circuit topology.The input amplitudes of the two sub-amplifiers and their phase difference is dynamically controlled leveraging on the dual-input technique,leading to reconfigurable operation modes from power allocation to Doherty.In the power allocation mode,flexible power allocation between two output ports can be obtained by the DIDO PA without sacrificing drain efficiency(DE).On the other hand,flexible power transferring and enhanced back-off DE can be simultaneously achieved by the DIDO PA when it is in the Doherty mode.As a proof of concept,a DIDO PA operating at 2.4 GHz is fabricated and measured in this paper.In the power allocation mode,the DIDO PA achieves a DE of more than 71.8%with a total output power of larger than 44 dBm.Moreover,when the DIDO PA operates in the Doherty mode,it could deliver a maximum output power of more than 44 dBm with a saturation DE of more than 73.9%and a 6 dB back-off DE of more than 61.2%.
基金supported by the National Key Research and Development Program of China(2023YFB3811502)the National Science Foundation of China(62225108)+5 种基金the Fundamental Research Funds for the Central Universities(2242022k60003)the National Natural Science Foundation of China(62288101 and 62201139)the Jiangsu Province Frontier Leading Technology Basic Research Project(BK20212002)the Jiangsu Provincial Scientific Research Center of Applied Mathematics(BK20233002)the Fundamental Research Funds for the Central Universities(2242024RCB0005 and 2242024K30009)the 111 Project(111-2-05).
文摘With digital coding technology,reconfigurable intelligent surfaces(RISs)become powerful real-time sys-tems for manipulating electromagnetic(EM)waves.However,most automatic RIS designs involve exten-sive numerical simulations of the unit,including the passive pattern and active devices,requiring high data acquisition and training costs.In addition,for passive patterns,the widely employed random pixe-lated method presents design efficiency and effectiveness challenges due to the massive pixel combina-tions and blocked excitation current flow in discrete patterns.To overcome these two critical problems,we propose a versatile RIS design paradigm with efficient topology representation and a separate design architecture.First,a non-uniform rational B-spline(NURBS)is introduced to represent continuous pat-terns and solve excitation current flow issues.This representation makes it possible to finely tune con-tinuous patterns with several control points,greatly reducing the pattern solution space by 20-fold and facilitating RIS optimization.Then,employing multiport network theory to separate the passive pat-tern and active device from the unit,the separate design architecture significantly reduces the dataset acquisition cost by 62.5%.Through multistep multiport calculation,the multistate EM responses of the RIS under different structural combinations can be quickly obtained with only one prediction of pattern response,thereby achieving dataset and model reuse for different RIS designs.With a hybrid continuous-discrete optimization algorithm,three examples—including two typical high-performance RISs and an ultra-wideband multilayer RIS—are provided to validate the superiority of our paradigm.Our work offers an efficient solution for RIS automatic design,and the resulting structure is expected to boost RIS appli-cations in the fields of wireless communication and sensing.
基金partially supported by the National Key Research and Development Project under Grant 2020YFB1806805Science and Technology on Communication Networks Laboratorysupported by China Scholarship Council.
文摘Reconfigurable intelligent surface(RIS)is a promising candidate technology of the upcoming Sixth Generation(6G)communication system for its ability to provide unprecedented spectral and energy efficiency increment through passive beamforming.However,it is challenging to obtain instantaneous channel state information(I-CSI)for RIS,which obliges us to use statistical channel state information(S-CSI)to achieve passive beamforming.In this paper,RIS-aided multiple-input single-output(MISO)multi-user downlink communication system with correlated channels is investigated.Then,we formulate the problem of joint beamforming design at the AP and RIS to maximize the sum ergodic spectral efficiency(ESE)of all users to improve the network capacity.Since it is too hard to compute sum ESE,an ESE approximation is adopted to reformulate the problem into a more tractable form.Then,we present two joint beamforming algorithms,namely the singular value decomposition-gradient descent(SVD-GD)algorithm and the fractional programming-gradient descent(FP-GD)algorithm.Simulation results show the effectiveness of our proposed algorithms and validate that 2-bits quantizer is enough for RIS phase shifts implementation.
基金supported in part by the National Key Research and Development Program of China under Grants 2023YFB3811505in part by the National Natural Science Foundation of China(NSFC)under Grants 62261160576,62201138,62301156,and 62401137+4 种基金in part by the Key Technologies R&D Program of Jiangsu(Prospective and Key Technologies for Industry)under Grants BE2023022-1 and BE2023022in part by the Natural Science Foundation of Jiangsu Province under Grant BK20220809 and BK20241281in part by the Fundamental Research Funds for the Central Universities under Grant 2242023K5003in part by the China National Postdoctoral Program for Innovative Talents under Grant BX20230065in part by the Jiangsu Excellent Postdoctoral Program under Grant 2023ZB476.
文摘Reconfigurable intelligent surface(RIS)has proven to be promising for future wireless communication.Due to its ability to manipulate electromagnetic(EM)waves,RIS provides a flexible and programmable way to implement intelligent wireless environments.While path loss modeling has been conducted in some prior research,an issue remaining unknown is the characteristics of multi-beam path loss for RIS.In this paper,we model,simulate and measure the multi-beam path loss in RIS-assisted broadcast communication scenarios.We propose two specific configurations of RIS and derive the path loss models,which reveal that the incident beam can be equally divided into multiple beams without power loss through rational design of the phase coding.The proposed path loss model is validated through simulation subsequently.To further verify our conclusions,we build a millimeter wave(mmWave)measurement system with a 35 GHz fabricated RIS.The measurement result corresponds well with the simulation,which shows a difference of about 3 dB in the received signal power of quad-beam compared with dual-beam,as well as dual-beam compared with single-beam,except for the impact of radiation patterns of the antennas and RIS elements.
