Results 71 to 80 of about 864,560 (239)

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

Study of Point Scanning Detection Mechanisms for Vibration Signals with Wavefront Sensors

Photonics
Seismic wave laser remote sensing is extensively employed in seismic monitoring and resource exploitation. This work establishes a vibration signal point scanning detection system utilizing wavefront sensors, leveraging their high resolution, array ...
Quan Luo, Hongsheng Luo, Yiyou Fan, Guihan Wu, Haoming Chen, Yun Pan, Wei Jiang, Jinshan Su   +7 more
doaj   +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

Higher-resolution wavefront sensing based on sub-wavefront information extraction

Frontiers in Physics
The limited spatial sampling rates of conventional Shack–Hartmann wavefront sensors (SHWFSs) make them unable to sense higher-order wavefront distortion.
Hongli Guan, Hongli Guan, Hongli Guan, Hongli Guan, Wang Zhao, Wang Zhao, Wang Zhao, Shuai Wang, Shuai Wang, Shuai Wang, Kangjian Yang, Kangjian Yang, Kangjian Yang, Mengmeng Zhao, Mengmeng Zhao, Mengmeng Zhao, Shenghu Liu, Shenghu Liu, Shenghu Liu, Shenghu Liu, Han Guo, Han Guo, Han Guo, Ping Yang, Ping Yang, Ping Yang   +25 more
doaj   +1 more source

Differential wavefront sensing and control using radio-frequency optical demodulation

, 2021
Differential wavefront sensing is an essential technique for optimising the performance of many precision interferometric experiments. Perhaps the most extensive application of this is for alignment sensing using radio-frequency beats measured with ...
Alexei Ciobanu (9240440), Daniel D. Brown (14384292), David Ottaway (10731891), Huy Tuong Cao (10731885), Peter Veitch (10731888)   +4 more
core   +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

Bio‐Inspired Gradient Coatings Enhance the Leading Edge Erosion Resistance of Wind Blades

Advanced Science, EarlyView.
Rain‐induced erosion of the wind turbine blade leading edge poses a critical challenge to maintenance and operation. Here, we propose a bio‐inspired approach for erosion protection utilising a platelet‐reinforced polyurethane coating with a graded through‐thickness architecture.
Natalia Sofia Guevara‐Sotelo, Julie Teuwen, Kunal Masania   +2 more
wiley   +1 more source

Investigation on compressed wavefront sensing in freeform surface measurements

, 2016
In this paper, conventional modal wavefront reconstruction is compared with compressed wavefront sensing to reconstruct freeform surface profiles using the Shack-Hartmann wavefront sensor.
Xin, Wang, Eddy, Chow Mun Tik, Tan, Ching Seong, Kuew, Wai Chew, Guo, Ningqun   +4 more
core   +1 more source

Neuromorphic Optical Tracking and Imaging of Randomly Moving Targets Through Dynamic Dense Scattering Media

Advanced Science, EarlyView.
Vision begins not with images but with change: the retina fires only when something moves, handing the brain a stream of spikes. A neuromorphic imaging system adopts the same strategy—an event sensor that sees like the retina, a spiking network that thinks like the brain—to track and reconstruct fully randomly moving targets through tissue (phantom ...
Ning Zhang, Arto Nurmikko
wiley   +1 more source

Ultra high precision wavefront sensing for Extreme-AO on ELTs

, 2010
High precision wavefront sensing is the key to detect low mass (potentially rocky) planets with ELTs. Ideally, a wavefront sensor for an Extreme-AO system should be both very sensitive (to allow high speed wavefront correction) and very accurate (to ...
O. Guyon
core   +1 more source