Results 21 to 30 of about 2,369 (180)

Ultrafast Optoacoustics Reveals Intricate 3D Anisotropic Elasticity in Nanocrystalline Membranes

Advanced Science, EarlyView.
Ultrafast optoacoustic spectroscopy combined with a Sagnac interferometer enables non‐contact, simultaneous characterization of thickness and the full three‐dimensional anisotropic elastic constants in freestanding nanocrystalline copper membranes. By capturing gigahertz Lamb waves and zero‐group‐velocity resonances followed by SAFE‐GA inversion, the ...
Shuchang Zhang, Yi He, Guojie Luo, Jie Huang, Pak San Yip, Haoyu Cui, Wanglinhan Zhang, Zijian Wang, Lin Ye, Yang Lu, Zhongqing Su, Yehai Li   +11 more
wiley   +1 more source

A Double-Threshold Channel Estimation Method Based on Adaptive Frame Statistics

Mathematics, 2023
Channel estimation is an important module to enhance the performance of orthogonal frequency division multiplexing (OFDM) systems. However, the presence of a large amount of noise in time-varying multipath fading channels significantly affects the ...
Canghai Song, Xiao Zhou, Chengyou Wang, Zhun Ye   +3 more
doaj   +1 more source

Review of Gastrointestinal Capsule Robots: Materials, Actuation, Diagnostics, and Therapeutics

Advanced Science, EarlyView.
This review examines gastrointestinal capsule robots through a systems engineering lens, covering shell materials, actuation and localization strategies, diagnostic modalities, therapeutic interventions, and commercialization status. By mapping the complete technological chain from fabrication to clinical deployment, this work identifies critical gaps ...
Zengsheng Li, Zhongguo Ren, Yiliang Lin, Xianfeng Xia, Tianlong Li, Kai Fung Chan, Philip Wai Yan Chiu, Wei Peng Yong, Mengmeng Sun   +8 more
wiley   +1 more source

Hierarchical Modulation Classification with Channel-Type-Guided Blind Preprocessing for High-Order QAM in Multipath Fading Channels

Applied Sciences
Automatic modulation classification (AMC) becomes challenging in multipath fading channels, particularly for high-order quadrature amplitude modulation (QAM) signals whose constellation points are strongly distorted by inter-symbol interference, phase ...
Sungsoo Park, Gyuyeol Kong
doaj   +1 more source

Single‐Sensor Vibration Sensing in Anisotropic Composites Enabled by Disordered Metasurfaces

Advanced Science, EarlyView.
This work develops a single‐sensor vibration sensing (SSVS) framework that integrates disordered metasurfaces with compressive sensing. Comprehensive numerical and experimental validations demonstrate that, by manipulating anisotropic guided wave propagation through metasurfaces, the proposed SSVS framework enables high‐fidelity multi‐source vibration ...
Jianjie Zhang, Lanhe Xu, Zhongzheng Zhang, Yongbo Li, Eric Li, Asoke K. Nandi, Bing Li   +6 more
wiley   +1 more source

Terahertz Channel Modeling, Estimation and Localization in RIS‐Assisted Systems

Advanced Electronic Materials, EarlyView.
Reconfigurable intelligent surfaces have become a recent intensive research focus. Based on practical applications, channel strategies for RIS‐assisted terahertz wireless communication systems are categorized into three different types: channel modeling, channel estimation, and channel localization.
Hongjing Wang, Weipeng Wang, Xuan Cong, Shiyu Wang, Gao Li, Sen Gong, Lin Huang, Hongxin Zeng, Yaxin Zhang, Ziqiang Yang   +9 more
wiley   +1 more source

Turbo Processing for Joint Channel Estimation, Synchronization, and Decoding in Coded MIMO-OFDM Systems

EURASIP Journal on Wireless Communications and Networking, 2009
This paper proposes a turbo joint channel estimation, synchronization, and decoding scheme for coded multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems.
Ko ChiChung, Nguyen-Le Hung, Le-Ngoc Tho
doaj   +2 more sources

An Intensity Measure‐Based Methodology for Ground Motion Orientation in Seismic Structural Assessment

Earthquake Engineering &Structural Dynamics, EarlyView.
ABSTRACT In current dynamic time history assessment protocols, ground motion recordings are mostly oriented along fixed sensor directions. Consequently, the orientation of the principal resultant of rupture energy, which may control the maximum structural demand, remains undefined, precluding consistent correlation with physically detrimental ...
Santiago Londono‐Lopez, Raffaele Cucuzza, Fabrizio Mollaioli, Giuseppe Carlo Marano, Marco Domaneschi   +4 more
wiley   +1 more source

Adaptive Subchip Multipath Resolving for Wireless Location Systems

EURASIP Journal on Advances in Signal Processing, 2006
Reliable positioning of cellular users in a mobile environment requires accurate resolving of overlapping multipath components. However, this task is difficult due to fast channel fading conditions and data ill-conditioning, which limit the performance ...
Yousef Nabil R, Sayed Ali H, Khajehnouri Nima   +2 more
doaj   +1 more source

Compensating for Channel Fading in DS-CDMA Communication Systems Employing ICA Neural Network Detectors [PDF]

Journal of Systemics, Cybernetics and Informatics, 2005
In this paper we examine the impact of channel fading on the bit error rate of a DS-CDMA communication system. The system employs detectors that incorporate neural networks effecting methods of independent component analysis (ICA), subspace estimation of
David Overbye, Roland Priemer
doaj