Results 101 to 110 of about 15,106 (288)

Radar near-field sensing using metasurface for biomedical applications

Communications Engineering
Metasurfaces, promising technology exemplified by their precise manipulation of incident wave properties and exquisite control over electromagnetic field propagation, offer unparalleled benefits when integrated into radar systems, providing higher ...
Mohammad Omid Bagheri, Ali Gharamohammadi, Serene Abu-Sardanah, Omar M. Ramahi, George Shaker   +4 more
doaj   +1 more source

A Dual‐Modal Wearable PPG Smartwatch with AI‐Enhanced Correction for High‐Accuracy and Continuous AF Burden Assessment

Advanced Science, EarlyView.
ABSTRACT Atrial fibrillation (AF) increases the risk of stroke and heart failure, yet accurate quantification of AF burden in daily life remains difficult. Although smartwatch photoplethysmography (PPG) supports continuous monitoring, complex rhythms and signal noise can impair burden estimation.
Song Zuo, Jinglei Wang, Xin Wang, Han Feng, Yize Zhao, Fadong Li, Shaobin Wei, Le Zhou, Zixu Zhao, Songjie Chen, Xiangyi Kong, Jue Wang, Liu He, Shijun Xia, Xin Li, Junmeng Zhang, Xiaoxia Liu, Xueyuan Guo, Ning Zhou, Songnan Li, Chenxi Jiang, Ribo Tang, Caihua Sang, Deyong Long, Xin Du, Jianzeng Dong, Wenwu Zhu, Changsheng Ma   +27 more
wiley   +1 more source

Exploiting Bulk Photovoltaic Effect in a Polar Hybrid Perovskite Towards Self‐Powered Detection of Weak Ultraviolet Polarized Light

Advanced Science, EarlyView.
Benefiting from intrinsic polarization, DJ‐type 2D perovskite crystals deliver self‐powered polarization‐resolved photocurrent under weak polarized UV light via the bulk photovoltaic effect, showing a high anisotropic factor of 8. ABSTRACT Weak light detection is essential for achieving high‐performance photodetectors with minimal power consumption ...
Xinyuan Zhang, Jianbo Wu, Wai‐Yeung Wong   +2 more
wiley   +1 more source

Bayesian sparse estimation of migrating targets in autoregressive noise for wideband radar [PDF]

, 2014
In recent work we showed the interest of using sparse representation techniques to estimate a target scene observed by wideband radar systems. However the principle was demonstrated in a white noise background only.
Bidon, Stéphanie, Stephanie Bidon, Jean-Yves Tourneret, Besson, Olivier, Le Chevalier, François, Olivier Besson, Francois Le Chevalier, Tourneret, Jean-Yves   +7 more
core   +1 more source

Space‐Time Metasurface Antenna Enabled High‐Dimensional Electromagnetic Modulation for Intrinsic Physical Layer Security

Advanced Science, EarlyView.
The concept of high‐dimensional EM modulation using the STMA for physical layer secure communication is illustrated in figure. The STMA consists of a series of programmable unit cells, with 1‐bit reconfigurable phase states (0/π). The STMA is excited by a monochromatic continuous wave (CW) at frequency fc and controlled by a field‐programmable gate ...
Xinyu Fang, Yiqing Sun, Chenfeng Yang, Siran Wang, Zheng Xing Wang, Kaixu Wang, Geng‐Bo Wu   +6 more
wiley   +1 more source

Hierarchical Physical‐Cyber Encryption via Metasurface‐Encoded Holographic Keys

Advanced Science, EarlyView.
ABSTRACT Physical‐layer encryption based on metasurfaces has emerged as a promising alternative to conventional algorithmic cryptography by embedding security into physical processes. However, most existing metasurface‐based encryption schemes operate within single‐stage or static frameworks, where correct physical illumination directly reveals the ...
Zhen Liu, Changhong Dai, Wei Zhu, Ruisheng Yang, Bohan Zhang, Lei Zhang, Bobo Du, Shengxiang Wang, Guangwei Hu   +8 more
wiley   +1 more source

Under-Foliage Object Imaging Using SAR Tomography and Polarimetric Spectral Estimators [PDF]

, 2012
International audienceThis paper addresses the imaging of objects located under a forest cover using polarimetric synthetic aperture radar tomography (POLTOMSAR) at L-band.
Huang, Yue, Andreas Reigber, Ferro-Famil, Laurent, Yue Huang, Reigber, Andreas, Laurent Ferro-Famil   +5 more
core   +1 more source

EndoTac: An Endoscopic Camera‐Based Tactile Sensor with High Sensitivity for Minimally Invasive Surgery

Advanced Science, EarlyView.
EndoTac presents a trocar‐compatible endoscopic vision‐based tactile sensor that uses a convex mirror to enlarge side‐facing tactile coverage during minimally invasive vessel palpation. Distorted tactile images are unwarped and processed by a learning model to estimate vascular deformation, enabling sensitive, spatially distributed tactile perception ...
Yupeng Wang, Nicolas Raison, Xuyang Zhang, Aijia Yang, Lukas Lindenroth, Shan Luo   +5 more
wiley   +1 more source

Research status and prospects of UWB radar life information recognition for mine rescue

Gong-kuang zidonghua
Ultra-wide band (UWB) radar can penetrate non-magnetic media such as coal and rock to detect life information of personnel after collapse. Due to the complex mining environment, UWB radar loaded with vital sign signals is prone to interference from ...
ZHENG Xuezhao, MA Yang, HUANG Yuan, CAI Guobin, DING Wen   +4 more
doaj   +1 more source

Liquid Metals in Radio Frequency Applications: A Review of Physics, Manufacturing, and Emerging Technologies

Advanced Electronic Materials, EarlyView.
This paper reviews the physics of liquid metals in RF devices, including the influence of mechanical strain on resonance as well as fabrication methods and strategies for designing tunable and strain‐tolerant inductors, capacitors, and antennas.
Md Saifur Rahman, William J. Scheideler
wiley   +1 more source