Results 41 to 50 of about 9,233 (214)

Orthogonal Polyphase Coded Waveform Design Method for Simultaneous Fully Polarimetric Radar

Leida xuebao, 2017
To obtain an accurate polarization scattering matrix, simultaneous full polarization radar systems must transmit two signals. The performance of orthogonal polyphase codes designed by the traditional method is limited by the code length and is sensitive ...
Wang Fulai, Pang Chen, Li Yongzhen, Wang Xuesong   +3 more
doaj   +1 more source

Improving the system capacity of broadband services using multiple high-altitude platforms [PDF]

, 2005
A method of significantly improving the capacity of high-altitude platform (HAP) communications networks operating in the millimeter-wave bands is presented. It is shown how constellations of HAPs can share a common frequency allocation by exploiting the
Chen, G.H., Grace, D., Thornton, J., Tozer, T.C., White, G.P.   +4 more
core   +1 more source

Real‐Time 3D Ultrasound Imaging with an Ultra‐Sparse, Low Power Architecture

Advanced Healthcare Materials, EarlyView.
This article presents a novel, ultra‐sparse ultrasound architecture that paves the way for wearable real‐time 3D imaging. By integrating a unique convolutional array with chirped data acquisition, the system achieves high‐resolution volumetric scans at a fraction of the power and hardware complexity.
Colin Marcus, Md Osman Goni Nayeem, Aastha Shah, Jason Hou, Shrihari Viswanath, Maya Eusebio, David Sadat, Anantha P. Chandrakasan, Tolga Ozmen, Canan Dagdeviren   +9 more
wiley   +1 more source

Transducers Across Scales and Frequencies: A System‐Level Framework for Multiphysics Integration and Co‐Design

Advanced Materials Technologies, EarlyView.
Transducers convert physical signals into electrical and optical representations, yet each mechanism is bounded by intrinsic trade‐offs across bandwidth, sensitivity, speed, and energy. This review maps transduction mechanisms across physical scale and frequency, showing how heterogeneous integration and multiphysics co‐design transform isolated ...
Aolei Xu, Mengyao Xiao, Zhouli Sui, Yinpeng Wang, Daoye Zheng, Yuxin Liu, Luwei Wang, Huajun Liu, Chengkuo Lee   +8 more
wiley   +1 more source

BA-Based Low-PSLL Beampattern Synthesis in the Presence of Array Errors

IEEE Access, 2022
In practical scenarios, there are always array errors, which would increase the sidelobe level (SLL) of the array and distort the performance of the electronic devices consequently.
Anyi Wang, Xuhong Li, Yanhong Xu
doaj   +1 more source

Random Time‐Space Coding Metasurfaces for Spatial Control of the Temporal Statistics of Electromagnetic Fields

Advanced Science, EarlyView.
A probabilistic framework based on random time‐space coding metasurfaces enables control of the spatial distribution of electromagnetic fields temporal statistics. By tailoring the marginal and joint distributions of random codes, electromagnetic fields with desired mean and variance patterns are realized, enabling simultaneous transmission and jamming.
Jia Cheng Li, Jiang Han Bao, Che Liu, Tie Jun Cui   +3 more
wiley   +1 more source

Sidelobe reduction for plane wave compounding with a limited frame number

BioMedical Engineering OnLine, 2018
Background In ultrasound plane wave imaging (PWI), image details are often blurred by the off-axis artefacts resulting from high sidelobe. Recently plane wave compounding (PWC) is proposed as a promising technique for the sidelobe suppression in the PWI.
Wei Guo, Yuanyuan Wang, Guoqing Wu, Jinhua Yu   +3 more
doaj   +1 more source

Nonlinear imaging through a golden spiral multicore fiber

, 2018
We report two-photon lensless imaging through a novel golden spiral multicore fiber. This unique layout optimizes the sidelobe levels, field of view, cross-talk, group delay and mode density to achieve a sidelobe contrast of atleast 10.9 dB.
Andresen, Esben, Bouwmans, Géraud, Rigneault, Hérve, Sivankutty, Siddharth, Tsvirkun, Viktor, Vanvincq, Olivier   +5 more
core   +3 more sources

Conformal Reconfigurable Intelligent Surfaces: A Cylindrical Geometry Perspective

Advanced Electronic Materials, EarlyView.
Cylindrical reconfigurable intelligent surfaces are explored for low‐complexity beam steering using one‐bit meta‐atoms. A multi‐level modeling approach, including optimization‐based synthesis, demonstrates that even minimal hardware can support directive scattering.
Filippo Pepe, Ivan Iudice, Giuseppe Castaldi, Marco Di Renzo, Vincenzo Galdi   +4 more
wiley   +1 more source

Metalens‐Enabled Twisted Chromatic Dispersion

Advanced Physics Research, EarlyView.
We successfully demonstrate visible broadband twisted dispersion metalenses. As a proof of concept, we realized two distinct devices: the conical helical and the spring‐like dispersion‐controlled metalenses. These results rigorously validate the universality of our approach in customizing arbitrary continuous 3D dispersion trajectories, thereby ...
Shiyu Zheng, Boyan Fu, Hong Zhang, Shuming Wang   +3 more
wiley   +1 more source