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arXiv 2025年

作者： Qin, Cheng-Gang Tan, Yu-Jie Lu, Xiao-Yu Liu, Tong Yang, Yan-Rui Li, Qin Shao, Cheng-Gang MOE Key Laboratory of Fundamental Physical Quantities Measurement Hubei Key Laboratory of Gravitation and Quantum Physics PGMF School of Physics Huazhong University of Science and Technology Wuhan430074 China Henan International Joint Laboratory of MXene Materials Microstructure College of Physics and Electronic Engineering Nanyang Normal University Nanyang473061 China Key Laboratory Of Space Utilization Technology And Engineering Center For Space Utilization Chinese Academy Of Sciences Beijing100094 China

Lorentz symmetry is a cornerstone of both the General relativity and Standard Model and its experimental verification deepens our understanding of nature. This paper focuses on the investigation of Lorentz violations with the context of clock comparison experiments in the framework of Standard Model Extension (SME). Considering matter-gravity coupling sector, we provide a generic frame to study the sensitivities of Lorentz-violating coefficients for three distinct types of clock redshift tests, including the traditional gravitational redshift test, null-redshift test I and null-redshift test II. Each of these tests is sensitivity to different combinations of Lorentz-violating coefficients. By using the current clock comparison results, we estimate the limits of SME coefficients at level of parts in 104 down to parts in 107. Better sensitivity may be achieved in the clock comparisons by using the state-of-the-art optical clocks. Additionally considering relativistic factors in null-redshift I, the frequency comparison result of E2 and E3 transitions of Yb+ can set the limit ce00 = (7.4±9.3)×10−9 in the electron sector. Our analysis demonstrates that clock-comparison redshift experiments may contribute to explore the vast parameters space on searching for the Lorentz violation. Copyright © 2025, The Authors. All rights reserved.

关键词： Relativity

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Wide measurement range and high sensitivity spongy MWCNT/polydimethylsiloxane pressure sensor based on a single-electrode enhanced triboelectric nanogenerator

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science China(Technological sciences) 2023年第6期66卷 1734-1745页

作者： XIE Xin HOU XiaoJuan QIAN Shuo HOU JianWei ZHANG Jie BI XiaoXue GENG WenPing MU JiLiang HE Jian CHOU XiuJian Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051China School of Software North University of ChinaTaiyuan 030051China

Flexible pressure sensors have broad application prospects,such as human motion monitoring and personalized ***,their applicability is limited by complex structures,low output performance,low sensitivity,and narrow measurement *** this study,we report a single-electrode spongy triboelectric sensor(SSTS)mainly composed of spongy composite multi-walled carbon nanotubes/polydimethylsiloxane(MWCNT/PDMS)film and conductive fabric,which can simultaneously generate contact electrification and electrostatic induction coupling in a single-electrode contact-separation *** SSTS combines the triboelectric effect,properties of doping material,and spongy porous structure(soft sugar as a sacrificial template).An SSTS with an MWCNT content of 10 wt%and a porosity of 64%exhibits high sensitivity,a wide measurement range,and excellent *** also displays two sensitivity regions(slopes):1.324 V/kPa from 1.5 to 28 kPa in the low-pressure range and 0.096 V/kPa from 28 to 316.5 kPa in the high-pressure range,with linearities of 0.980 and 0.979,***,the SSTS delivers a high-performance output and high stability,thus enhancing the monitoring of hand pressure changes,human movement,personalized spatial recognition,and other detection *** new strategy for human motion monitoring shows great potential in the healthcare fields,sports rehabilitation,and human-computer interactions.

关键词： triboelectric nanogenerator spongy pressure sensor single-electrode high sensitivity wide measurement range

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Flexible multilayer MEMS coils and their application in energy harvesters

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science China(Technological sciences) 2024年第4期67卷 1282-1293页

作者： ZHANG Jie HOU XiaoJuan QIAN Shuo BI XiaoXue HU DongXu LIU JianJun GENG WenPing MU JiLiang HE Jian CHOU XiuJian Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051China School of Software North University of ChinaTaiyuan 030051China

Electromagnetic vibration energy harvesters are promising for the power supply of wireless sensor nodes,small electronic devices,and wearable *** electromagnetic harvesters usually increase output by increasing the size of coils and magnets,limiting the improvement of energy conversion efficiency and power *** this study,multilayer microelectromechanical system(MEMS)coils were prepared using flexible electronics,and their high integration performance in arbitrary space was utilized to greatly improve the utilization of the space magnetic field by the electromagnetic *** core magnet of the generator was magnetically balanced to achieve levitation,which improved the sensitivity and reduced fatigue damage compared with traditional spring *** wound coils on the top and bottom of the magnet and the flexible coils on the sides worked together to improve the energy efficiency and output of the *** output performance of the device with different number distributions was simulated using mathematical models to obtain the optimal structural *** results show that by introducing flexible multilayer MEMS coils on the side surface of the energy harvester,the open-circuit voltage of the energy generators increased from 7 to 10 V by more than 43%.Flexible multilayer MEMS coils can enhance energy conversion rates and possess compact dimensions,making them suitable for integration onto complex *** the vibration energy harvesting system testing,the maximum peak power of the harvester was 7.1 m W at an acceleration of1 g and a resonant frequency of 11 Hz with a resistor of 3.5 kΩinternal ***,a 470μF capacitor can be charged to 3.5 V within 10 s to drive a hygrothermograph to work for more than 80 s and can supply a light bulb *** strategy shows the great potential of vibration-energy-driven electromagnetic generators for powering small electronics in limited spaces.

关键词： electromagnetic harvester mechanical energy harvesting multilayer MEMS coils magnetic levitation overall space magnetic field flexible planar coils

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A high-sensitivity flexible bionic tentacle sensor for multidimensional force sensing and autonomous obstacle avoidance applications

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Microsystems & Nanoengineering 2024年第5期10卷 265-276页

作者： Xinyu Liu Kunru Li Shuo Qian Lixin Niu Wei Chen Hui Wu Xiaoguang Song Jie Zhang Xiaoxue Bi Junbin Yu Xiaojuan Hou Jian He Xiujian Chou Science and Technology on Electronic Test and Measurement Laboratory North University of China030051 TaiyuanChina School of Software North University of China030051 TaiyuanChina

Bionic tentacle sensors are important in various fields,including obstacle avoidance,human-machine interfaces,and soft ***,most traditional tentacle sensors are based on rigid substrates,resulting in diffculty in detecting multidirectional forces originating from the external environment,which limits their application in complex ***,we proposed a high-sensitivity flexible bionic tentacle sensors(FBTSs).Specifically,the FBTS featured an ultrahigh sensitivity of 37.6 N-1 and an ultralow detection limit of 2.4 mN,which benefited from the design of a whisker-like signal amplifier and crossbeam ***,the FBTS exhibited favorable linearity(R^(2)=0.98)and remarkable durability(more than 5000 cycles).This was determined according to the improvement in the uniformity of the sensing layer through a high-shear dispersion *** addition,the FBTS could accurately distinguish the direction of external stimuli,resulting in the FBTS achieving roughness recognition,wind speed detection and autonomous obstacle *** particular,the ability of autonomous obstacle avoidance was suitably demonstrated by leading a bionic rat through a maze with the ***,the proposed FBTS could be widely applied in tactile sensing,orientation perception,and obstacle avoidance.

关键词： obstacle autonomous durability

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Design of Low Spurious Phase Locked Loop for Vector Network Analyzer 6

Design of Low Spurious Phase Locked Loop for Vector Network ...

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6th IEEE International Conference on Computer and Communication Systems, ICCCS 2021

作者： Chen, Engang Zhang, Qinglong Yang, Yubin Cao, Zhiying Sun, Shengkai Science and Technology on Electronic Test Measurement Laboratory Qingdao China

ISBN: (纸本)9780738126043

In the vector network analyzer, the excitation source signal will produce nonlinear compression after being amplified for many times, resulting in the reduction of spurious rejection ratio. In power measurement, the spurious signal is detected as the main signal, while in narrowband reception, the spurious signal is filtered out and the amplitude decreases on the curve. This paper introduces a method to improve the spurious suppression of excitation signal. The spurious suppression is increased by 18dB. © 2021 IEEE.

关键词： Phase locked loops

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Porous fiber paper and 3D patterned electrodes composed high-sensitivity flexible piezoresistive sensor for physiological signal monitoring

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science China(Technological sciences) 2022年第5期65卷 1169-1178页

作者： HOU XiaoJuan ZHONG JiXin HE Jian YANG ChangJun YU JunBin MEI LinYu MU JiLiang GENG WenPing CHOU XiuJian Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan030051China School of Mechanical Engineering North University of ChinaTaiyuan030051China

The research on flexible pressure sensors has drawn widespread attention in recent years,especially in the fields of health care and intelligent *** practical applications,the sensitivity of sensors directly affects the precision and integrity of weak pressure ***,a pressure sensor with high sensitivity and a wide measurement range composed of porous fiber paper and 3D patterned electrodes is ***-walled carbon nanotubes with excellent conductivity were evenly sprayed on the fiber paper to form the natural spatial conducting networks,while the copper-deposited polydimethylsiloxane films with micropyramids array were used as electrodes and flexible *** conducting paths between electrodes and fibers can be obtained when high-density micro-pyramids fall into the porous structures of the fiber paper under external pressure,thereby promoting the pressure sensor to show an ultra-high sensitivity of 17.65 kPa^(-1)in the pressure range of 0–2 kPa,16 times that of the device without patterned ***,the sensor retains a high sensitivity of 2.06 kPa^(-1)in an ultra-wide measurement range of 150 ***,the sensor can detect various physiological signals,including pulse and voice,while attached to the human *** work provides a novel strategy to significantly improve the sensitivity and measurement range of flexible pressure sensors,as well as demonstrates attractive applications in physiological signal monitoring.

关键词： flexible pressure sensor high sensitivity wide measurement range fiber paper 3D patterned electrodes physiological signal monitoring

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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao Jian Zheng Jin Guo Yunbo Shi Hengzhen Feng Jun Tang Jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

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Design of a Broadband Quadruple-frequency Amplitude-stabilized Source Module Applied to THz Imaging System 9

Design of a Broadband Quadruple-frequency Amplitude-stabiliz...

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2016 IEEE 9th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies

作者： Shibin Zhang Guoqing Fan Dengbao Li Science and Technology on Electronic Test & Measurement Laboratory The 41st Institute of CETC

ISBN: (纸本)9781509022779

THz imaging technology requires high frequency and stabilized source signal,but direct generation of high frequency and pure signal is difficult,so frequency multiplier technology is important to meet various requirements.A broadband quadruple-frequency amplitude-stabilized source module is presented in this *** quadruple-frequency source module has the characteristics of good amplitude-stability,broad working frequency band,high-purity signal,small size and light weight,*** working band is very broad,output frequency band is *** inter-digital bandpass filters with sharp falling edges are designed to ensure purity of quadruple-frequency *** results show that fundamental suppression is better than 60 dBc and other harmonic suppression is better than 45 dBc in whole frequency *** source module has high stability and anti-interference characteristic,and output power remains constant when input signal power *** quadruple-frequency module has been successfully applied to active THz imaging system as a front-stage amplitude-stabilized signal source.

关键词： source broadband quadruple-frequency amplitude-stabilized THz imaging system

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Design of A Novel Conical Conformal Linear Array Antenna for C-band Application 6

Design of A Novel Conical Conformal Linear Array Antenna for...

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2019 6th International Conference on Advanced Composite Materials and Manufacturing Engineering, ACMME 2019

作者： Xu, Hongcheng Zhang, Binzhen Duan, Junping Science and Technology on Electronic Test and Measurement Laboratory Taiyuan Shanxi China

A Novel conical conformal linear array antenna made up of 7 elements is proposed in this paper. Each element employing independent feeding consists of the overlapping top square, medium dielectric layer, array supported layer and back ground. The linear array antenna is wrapped around a conical surface to realize the integration. Through analyzing element working performance and linear array antenna on plane, the conformal array antenna wrapped around a conical surface just smaller curvature can be of analogy to reduce the experimental process. The presented conformal antenna operates at 4.86GHz over C-band. Multi-ports excitations have a vigorous characteristic in terms of a wide scanning angle and high gain than 10dBi. This method of the conformal array antenna analysis and the proposed design of antenna array integrating with supported layer can be employed a morph antenna and reduce the manufacturing cost for C-band. © Published under licence by IOP Publishing Ltd.

关键词： Antenna arrays

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ASTARS Aided NOMA Covert Communication Networks

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IEEE Transactions on Vehicular technology 2025年

作者： Yue, Xinwei Song, Xinlong Zhao, Jingjing Huang, Chongwen Jin, Hongxu Xiang, Wei Key Laboratory of Information and Communication Systems Ministry of Information Industry Beijing102206 China Beijing Information Science and Technology University Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing102206 China Beihang University School of Electronic and Information Engineering Beijing100191 China Zhejiang University College of Information Science and Electronic Engineering Hangzhou310027 China Xidian University State Key Laboratory of Integrated Service Networks Xi'an710071 China Hangzhou310027 China Zunyi Normal University School of Information Engineering Zunyi563006 China La Trobe University School of Computing Engineering and Mathmatical Sciences MelbourneVIC3086 Australia

The active simultaneously transmitting and reflecting surface (STARS) has been proposed as a complement of passive STARS (PSTARS) to inhibit the double path-loss. This paper applies the active STARS (ASTARS) to aid in non-orthogonal multiple access (NOMA) covert communications over cascaded rice fading channels, where two wardens are located on the opposite sides of ASTARS to monitor the transmission information. More specifically, we derive approximate expressions for detection error probability of two wardens. The optimal detection threshold and minimum detection error probability are presented in the worst covert scenarios. The covert transmission rate expressions for a coupe of covert users are further deduced by taking into account imperfect/perfect successive interference cancellation. The experimental simulation results are presented to confirm that: 1) The detection error probability of ASTARS-NOMA networks is superior to that of ASTARS assisted-orthogonal multiple access (ASTARS-OMA) and PSTARS aided NOMA networks;2) As the number of active elements increases, the covert transmission rates of ASTARS-NOMA networks become larger relative to ASTARS-OMA;and 3) ASTARS-NOMA has ability to provide the enhanced system throughput in delay-tolerant transmission mode. © 2025 IEEE.

关键词： Fading channels

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