Results 71 to 80 of about 7,393 (258)

Influence of the Antennas on the Ultra-Wideband Transmission

EURASIP Journal on Advances in Signal Processing, 2005
Summary: Spectrum is presently one of the most valuable goods worldwide as the demand is permanently increasing and it can be traded only locally. Since the United States Federal Communications Commission (FCC) has opened the spectrum from 3.1 GHz to 10.6 GHz, that is, a bandwidth of 7.5 GHz, for unlicensed use with up to -41.25 dBm/MHz EIRP, numerous ...
Sörgel, W., Wiesbeck, Werner
openaire   +2 more sources

Omnidirectional Ultra‐Broadband Cu/TiO2 Metasurface Absorbers for High‐Efficiency Solar Thermal Conversion and Photothermal Plasmon‐Driven Catalysis

Advanced Optical Materials, EarlyView.
Metasurface shows selective solar–thermal energy conversion with high‐activity solar/laser‐driven chemistry. The breakthrough is co‐designing broadband FP‐cavity + plasmonic LSPR/SLR resonances in an ultra‐thin metamaterial so that it not only harvests the most efficient proportion of solar radiation but also suppresses mid and IR emissivity. Moreover,
Samira Mehrabi, HaoYu Zhang, Narendra Chaulagain, Edgar Acosta, Nazir P. Kherani   +4 more
wiley   +1 more source

Spectral Compensation Strategy for Radical‐Induced Dye Degradation in Liquid Crystal Polymer Composites

Advanced Optical Materials, EarlyView.
A spectral compensation strategy is introduced to overcome radical‐induced degradation of dichroic dyes during UV photopolymerization. By incorporating a complementary photochromic liquid‐crystalline dye, broadband optical attenuation is preserved without disrupting photopolymerization, enabling high‐contrast and durable dye‐doped liquid crystal ...
Wei‐Hsien Wu, Li‐Min Chang, Yu‐Hsuan Peng, Hsiu‐Hui Chen, Chun‐Ta Wang   +4 more
wiley   +1 more source

Harnessing Ultrafast Optical Pulses for 3D Microfabrication by Selective Tweezing and Immobilization of Colloidal Particles in an Integrated System

Advanced Photonics Research, Volume 6, Issue 5, May 2025.
Microfabrication using nano‐ to micron‐sized blocks has transformative potential for next‐gen electronics, optoelectronics, and materials. Traditional methods are limited by scalability and precision. STIC, a single‐laser system for precise colloid manipulation and immobilization using femtosecond lasers, is introduced that enables efficient 3D ...
Krishangi Krishna, Jieliyue Sun, Wenyu Liu, Robert H. Hurt, Kimani C. Toussaint Jr.   +4 more
wiley   +1 more source

Perspective: Hollow Core Optical Fibres for Ultraviolet and Visible Wavelengths

Advanced Science, EarlyView.
Hollow core optical fibres bypass material constraints that limit optical fibres at ultraviolet and visible wavelengths. However, their challenging fabrication has limited their development, and significant gains in performance remain possible. In this perspective we outline approaches to enable the next generation of fibres for shorter wavelengths ...
Robbie Mears, Kerrianne Harrington, Jonathan C. Knight, William J. Wadsworth, James M. Stone, Tim A. Birks   +5 more
wiley   +1 more source

Photonic Time Crystals and Time‐Varying Electromagnetic Metamatter: A New Direction for Ultrafast Tunable Photonic and Microwave Materials and Devices

Advanced Science, EarlyView.
Photonic time crystals (PTCs) are systems in which electromagnetic parameters are modulated periodically in time, producing momentum bandgaps via temporal scattering rather than spatial Bragg processes. This review examines the theoretical frameworks, modeling, and computational tools for time‐varying media, and summarizes experimental demonstrations ...
Ranjan Kumar Patel, Shriram Ramanathan, Ronald P. Jenkins, Michael J. Carter   +3 more
wiley   +1 more source

An On‐Demand Neuromorphic Vision System Enabled by a Multi‐Paradigm Neuromorphic Device and Hierarchical Reconfigurability Designed from Device to System Level

Advanced Science, EarlyView.
An on‐demand ultra‐reconfigurable intelligent vision system with hierarchical reconfigurability from device to system levels is demonstrated. Through co‐design of a multi‐paradigm device, reconfigurable circuits, and adaptive system architecture/algorithms, the system enables seamless switching among spiking, non‐spiking, neuromorphic imaging (NI), and
Biyi Jiang, Jiayi Xu, Liang Ran, Xinhe Feng, Khalil Harrabi, Yida Li, Longyang Lin, Feichi Zhou   +7 more
wiley   +1 more source

Polymorphic Superparaelectric Engineering Boosting Energy Storage Capacity in BaTiO3‐Based Ceramics

Advanced Science, EarlyView.
Herein, Ca2+ incorporation promotes the coexistence of CaTiO3‐/BaTiO3‐derived paraferroelectric states, stabilizing cubic‐orthorhombic‐tetragonal polymorphic superparaelectric phases. This minimizes polarization energy barriers, facilitating full polarization saturation without compromising efficiency.
Pan Liu, Xiang Ren, Jin Qian, Haihua Huang, Peng Li, Peng Fu, Jigong Hao, Huarong Zeng, Wei Li, Zhenxiang Cheng   +9 more
wiley   +1 more source

An Ultra-Wideband Reflective Phase Gradient Metasurface Using Pancharatnam-Berry Phase

IEEE Access, 2019
Designing a transmissive and reflective phase gradient metasurface (PGM) using Pancharatnam-Berry (PB) geometrical phase must be based on an appropriate metasurface, which can realize circular-polarization (CP)-conversion transmission and CP-maintaining ...
Baoqin Lin, Jianxin Guo, Lintao Lv, Zhe Liu, Xiang Ji, Jing Wu   +5 more
doaj   +1 more source

Directive Ultra-Wideband Planar Antennas

, 2010
Since the acceptance of unlicensed use of the Ultra-Wideband (UWB) technology in the range between 3.1 and 10.6 GHz in the USA (FCC, 2002) and more recently between 3.4 and 8.5 GHz in Europe (ETSI, 2008), the realization of low-cost UWB wireless systems is considered a fundamental research goal both for military and commercial applications.
CAPOBIANCO AD, PIGOZZO FM, LOCATELLI, Andrea, MODOTTO, Daniele, DE ANGELIS, Costantino, BOSCOLO S, SACCHETTO F, MIDRIO M.   +7 more
openaire   +5 more sources