Results 31 to 40 of about 7,278 (256)

Ultra-Wideband Low-RCS Circularly-Polarized Metasurface-Based Array Antenna Using Tightly-Coupled Anisotropic Element

IEEE Access, 2018
A novel broadband circular-polarized array antenna with ultra-wideband low radar cross section (RCS) is proposed. The array is made up of 2 × 2 identically circular-polarized sub-arrays in a chessboard configuration.
Lili Cong, Xiangyu Cao, Jun Gao, Tao Song   +3 more
doaj   +1 more source

Designing Polymer Nanocomposites for X‐Ray Shielding: Mechanisms, Architectures, and Scalable Processing

Advanced Engineering Materials, EarlyView.
This review highlights advances in lightweight, lead‐free polymer nanocomposites for diagnostic X‐ray shielding. By linking filler chemistry, dispersion, architecture, and photon interaction mechanisms, it establishes structure–performance relationships guiding material design.
Aklilu G. Messele, Hossein Ipakchi, Tizazu H. Mekonnen   +2 more
wiley   +1 more source

The Role of Ultra‐Thin Buffer Layers for Achieving Ultra‐Low Dark Currents in Single‐Component Organic Photodetectors

Advanced Functional Materials, EarlyView.
Here, SubNc single‐component organic photodiodes (SC‐OPDs) are investigated, which achieve highly competitive performance metrics, including high EQE, ultra‐low JD, and high specific detectivity (D*). This study emphasizes the critical role of an organic buffer layer in studying the interface energetics and effects to achieve state‐of‐the‐art ...
Anncharlott Kusber, Ying Sun, Jakob Wolansky, Louis Conrad Winkler, Anna‐Lena Hofmann, Fred Kretschmer, Hrisheekesh Thachoth Chandran, Tianyi Zhang, Mike Hambsch, Stefan C. B. Mannsfeld, Karl Leo, Ji‐Seon Kim, Johannes Benduhn   +12 more
wiley   +1 more source

Ultra-wideband SAR Tomography on asteroids

Radio Science, 2020
Abstract Our knowledge of the internal structure of asteroids is currently indirect and relies on inferences from remote sensing observations of surfaces. However, it is fundamental for understanding small bodies' history and for planetary defense missions.
Oriane Gassot, Alain Herique, Wenzhe Fa, Jun Du, Wlodek Kofman   +4 more
openaire   +3 more sources

High‐Index, Low‐Loss Optical Material Platforms for Ultra‐Broadband Ultraviolet‐to‐Visible Achromatic Metalenses

Advanced Functional Materials, EarlyView.
An integrated material platform combining engineered SiNx thin films and printable ZrO2 nanoparticle‐embedded resin enables broadband achromatic metalenses from the ultraviolet to visible range. The demonstrated meta‐optics achieve near‐diffraction‐limited focusing with minimal chromatic aberration.
Hyunjung Kang, Dongmin Jeon, Eunji Lee, Junsuk Rho   +3 more
wiley   +1 more source

A 180 nm CMOS dual-mode LNA with current reuse and double-resonance load for 2.4 GHz and 3.1–10.6 GHz wireless communication

Scientific Reports
This paper presents the design and post-layout analysis of a dual-mode low-noise amplifier (LNA) operating in both narrowband (2.4 GHz) and ultra-wideband (3.1 GHz–10.6 GHz) frequency ranges, aimed at wireless communication applications.
Thammaneni Snehitha Reddy, Vijay Nath
doaj   +1 more source

Method of estimation of frequency parameters of ultra-wideband signals with an unknown spectrum shape in the presence of interference

Физика волновых процессов и радиотехнические системы
Background. One of the urgent tasks of processing ultra-wideband signals is the assessment of their frequency parameters in complex signal-noise conditions. Aim.
The Tuan Doan, Pavel A. Trifonov
doaj   +1 more source

Chiral Phase Change Nanomaterials

Advanced Functional Materials, EarlyView.
This work demonstrates reversible, non‐volatile phase transitions in chiral Ge2${\rm Ge}_2$Sb2${\rm Sb}_2$Te5${\rm Te}_5$ (GST) nanohelices for high‐speed optical modulation of chirality and dynamic control of the state of polarization (SOP). The chiral nanostructures are fabricated using a highly directional, wafer‐scale physical vapor deposition ...
Joshua A. Burrow, Md Shah Alam, Riad Yahiaoui, Evan M. Smith, Ryan Laing, Jules Gardener, Thomas A. Searles, Piyush J. Shah, Shivashankar Vangala, Joshua R. Hendrickson, Andrew M. Sarangan, Imad Agha   +11 more
wiley   +1 more source

An Ultra-Wideband Frequency System for Non-Destructive Root Imaging

Sensors, 2018
Understanding the root system architecture of plants as they develop is critical for increasing crop yields through plant phenotyping, and ultra-wideband imaging systems have shown potential as a portable, low-cost solution to non-destructive imaging ...
Thomas Truong, Anh Dinh, Khan Wahid
doaj   +1 more source

Dye‐Initiated Chirped Cholesteric Polymer Networks Exhibiting Broadband Dissipative Chiral Photonic Bands

Advanced Functional Materials, EarlyView.
A dye‐based photoinitiator acting as a structure‐directing element, guides the formation of a cholesteric polymer network that behaves as a chirped photonic structure with dissipative chiral coupling. Photopolymerization freezes a depth‐dependent helical pitch, broadening the Bragg resonance spectrum.
Alfredo Mazzulla, Pasquale Pagliusi, Gabriella Cipparrone   +2 more
wiley   +1 more source