Scholars@Duke
David R. Smith

David R. Smith

James B. Duke Distinguished Professor of Electrical and Computer Engineering
Pierre R. Lamond Department of Electrical and Computer Engineering
drsmith@duke.edu
Box 90291, Durham, NC 27708-0291
2527 CIEMAS Building, Durham, NC 27708

Scholarly Works - Conferences

Determination of Energy Resolution for YSO:Ce Detector Modelled with FLUKA Code

Conference 2022 IEEE NSS Mic Rtsd IEEE Nuclear Science Symposium Medical Imaging Conference and Room Temperature Semiconductor Detector Conference · January 1, 2022 In this paper, a 5×5×5 mm3 YSO:Ce scintillator detector was modelled with FLUKA code, and calculations for the determination of energy resolution are reported using energies of 59.5, 81, 356, and 661.7 keV. We measured the energy resolution of t ... Full text Cite

A portable test-bench for real-time radiation damage measurements in scintillating and wavelength-shifting fibres

Conference 2019 IEEE Nuclear Science Symposium and Medical Imaging Conference NSS Mic 2019 · October 1, 2019 A portable test-bench has been developed to enable the real-time measurement of radiation-induced absorption in scintillating and wavelength-shifting fibres. Such fibres are typically used in the readout of fibre calorimeters or scintillating tiles such as ... Full text Cite

Cost-effective Integration System of Solar Cell Powered Remote Small-Size Wireless Communication

Conference 2nd International Conference on Electrical Communication Computer Power and Control Engineering Iceccpce 2019 · February 1, 2019 in this paper, a cost-effective design technique of a combined photovoltaic solar system, with electrical energy storage (ESS) for remote areas wireless long-term communication integration system is presented and discussed. Solar systems are the only possi ... Full text Cite

A reconfigurable millimeter-wave spotlight metasurface aperture integrated with a frequency-diverse microwave imager for security screening

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2018 In this paper, a spotlight imaging system integrated with a frequency-diverse aperture is presented for security-screening applications. The spotlight imager consists of holographic metasurface antennas that can dynamically be tuned to radiate spotlight pa ... Full text Cite

Synthetic aperture radar imaging with reconfigurable 1d dynamic metasurface apertures

Conference Proceedings of the European Conference on Synthetic Aperture Radar Eusar · January 1, 2018 Driven by the growing need for lightweight and low-cost antennas, we investigate metasurface antennas as a potential SAR hardware platform. Metasurface antennas can generate arbitrary radiation patterns and electronically modulate them without requiring co ... Cite

Spatial intensity averaging for ghost imaging with a single-port dynamic metasurface aperture

Conference Optics Infobase Conference Papers · January 1, 2018 We present a method for achieving spatial intensity integration of temporally coherent microwave radiation. The approach consists of averaging the instantaneous intensity over an ensemble of random radiation patterns using a single-port metasurface apertur ... Full text Cite

Reflective microwave ghost imaging with dynamic metasurface apertures

Conference Optics Infobase Conference Papers · January 1, 2018 We demonstrate phaseless, single-frequency ghost imaging at microwave frequencies using a dynamic metasurface aperture. This aperture comprises a simplified hardware architecture for generating diverse speckle patterns by tuning an array of resonant metama ... Full text Cite

Phase Retrieval in Frequency-Diverse Imaging

Conference 2018 IEEE Antennas and Propagation Society International Symposium and Usnc Ursi National Radio Science Meeting Apsursi 2018 Proceedings · January 1, 2018 We demonstrate a phaseless computational frequency-diverse imaging system at K-band frequencies. The integration of the phase retrieval concept with computational frequency-diverse imaging is achieved by leveraging a gradient-descent based Wirtinger Flow a ... Full text Cite

Dipolar Model for Metamaterial Imaging Systems

Conference 2018 IEEE Antennas and Propagation Society International Symposium and Usnc Ursi National Radio Science Meeting Apsursi 2018 Proceedings · January 1, 2018 We present a comprehensive simulation platform for computational microwave imaging systems based on frequency-diverse metasurface antennas (FDMAs). FDMAs consist of a waveguide patterned with complementary metamaterial elements with resonant frequencies se ... Full text Cite

Design of a Reconfigurable Metasurface Antenna for Dynamic Near-Field Focusing

Conference 2018 IEEE Antennas and Propagation Society International Symposium and Usnc Ursi National Radio Science Meeting Apsursi 2018 Proceedings · January 1, 2018 We show the design of a dynamically reconfigurable holographic metasurface antenna for near-field beam-focusing applications. A metasurface layer is used to modulate the guided-mode reference to an aperture field of interest producing the desired radiated ... Full text Cite

Computational Millimeter-wave Spotlight Imaging using Holographic Metasurface Antennas

Conference 2018 IEEE Antennas and Propagation Society International Symposium and Usnc Ursi National Radio Science Meeting Apsursi 2018 Proceedings · January 1, 2018 In this paper, a spotlight imaging system integrated with a frequency-diverse aperture is presented for security-screening applications. The spotlight imager consists of holographic metasurface antennas that can dynamically be tuned to radiate spotlight pa ... Full text Cite

Additive Manufacturing of a Conductive Polymer Cavity-Backed Metasurface Antenna for Computational Microwave Imaging

Conference 2018 IEEE Antennas and Propagation Society International Symposium and Usnc Ursi National Radio Science Meeting Apsursi 2018 Proceedings · January 1, 2018 We demonstrate a new 3D printing technique, making use of a copper-polyester conductive composite filament (Electrifi) to achieve additive manufacturing of a frequency-diverse metasurface antenna. Using the 3D printed antenna, we synthesize a computational ... Full text Cite

Extracting polarizability of complementary metamaterial elements using equivalence principles

Conference 2017 11th International Congress on Engineered Material Platforms for Novel Wave Phenomena Metamaterials 2017 · November 14, 2017 A novel Metamaterial Dipole Model (MDM) has been proposed as a powerful tool for modeling and designing metasurface antennas for numerous applications such as beamforming arrays, holograms, and flat lenses among others. In this technique, a metasurface ant ... Full text Cite

Multispectral metasurface absorbers for optoelectronic devices

Conference 2017 Conference on Lasers and Electro Optics CLEO 2017 Proceedings · October 25, 2017 We demonstrate multispectral metasurfaces over wafer-scale areas exhibiting greater than 85 percent absorption, ~100 nm linewidths from 580-1125 nm by patterning plasmonic resonators in micron-scale pixels using a fusion of bottom-up and top-down fabricati ... Full text Cite

Synthesizing a frequency-diverse aperture for security-screening applications

Conference 2017 IEEE Antennas and Propagation Society International Symposium Proceedings · October 18, 2017 We demonstrate the design of a frequency-diverse aperture for imaging of human size objects. Frequency-diversity is an all-electronic technique, allowing the imaging to be performed without any mechanical moving parts or active circuit components. Leveragi ... Full text Cite

Alignment Correction for antenna scans in imaging

Conference 2017 IEEE Antennas and Propagation Society International Symposium Proceedings · October 18, 2017 In this paper, we propose a software correction technique to eliminate the misalignment errors in the measurement of antenna radiated fields for frequency-diverse imaging. It is shown that by using RF fiducials integrated into the antennas, the effect of r ... Full text Cite

Computational polarimetric localization with a radiating metasurface

Conference 2017 IEEE Antennas and Propagation Society International Symposium Proceedings · October 18, 2017 A novel computational technique is presented in this article for enabling the estimation of both the localization of radiating sources and their polarization states. To this end, a radiating metasurface is conceived to multiplex the polarization informatio ... Full text Cite

Optimised lambda architecture for monitoring wlcg using spark and spark streaming

Conference 2016 IEEE Nuclear Science Symposium Medical Imaging Conference and Room Temperature Semiconductor Detector Workshop NSS Mic Rtsd 2016 · October 16, 2017 Full text Cite

Millimetre wave front end receivers for the MWS and MWI instruments onboard MetOp-SG satellites

Conference International Conference on Infrared Millimeter and Terahertz Waves Irmmw Thz · October 12, 2017 RAL Space and its project partner PRG are tasked with providing space-qualified heterodyne receiver front-ends operating between 165.5 GHz and 325 GHz for the Microwave Sounder (MWS), the Microwave Imager (MWI) and the Ice Cloud Imager (ICI) of the MetOp S ... Full text Cite

Discrete dipole approximation for simulation of unusually tapered leaky wave antennas

Conference IEEE MTT S International Microwave Symposium Digest · October 4, 2017 In this paper, Discrete Dipole Approximation (DDA) is presented as a simulation tool for predicting the electromagnetic properties of one dimensional metasurface antennas and slotted waveguide antennas. The proposed method is verified by demonstrating exce ... Full text Cite

Investigation of RF and DC plasma electron sources for material processing applications

Conference Ivec 2017 18th International Vacuum Electronics Conference · July 2, 2017 This work presents the design, development and experimental results obtained from an RF plasma cathode Electron Beam (EB) gun for material processing applications. EB currents of up to 38 mA at -60 kV were extracted and correlated to Optical Emission Spect ... Full text Cite

Computational imaging using frequency-diverse metasurfaces

Conference 2017 11th European Conference on Antennas and Propagation Eucap 2017 · May 15, 2017 This paper summarizes the recent advances in using frequency-diverse metasurfaces for computational imaging in the microwave and millimeter wave regimes. Frequency-diverse apertures are defined as structures that can generate distinct radiation patterns as ... Full text Cite

Computational frequency-diverse microwave imaging using an air-filled cavity-backed antenna

Conference 2017 11th European Conference on Antennas and Propagation Eucap 2017 · May 15, 2017 We demonstrate a frequency-diverse imaging system using an air-filled cavity-backed antenna as a transceiver (cavity-to-cavity system layout) for the K-band (17.5-26.5 GHz) frequency regime. Leveraging the computational imaging concept, the frequency-diver ... Full text Cite

Optimization of frequency-diverse antennas for computational imaging at microwave frequencies

Conference 2017 11th European Conference on Antennas and Propagation Eucap 2017 · May 15, 2017 Frequency-diverse imaging is an all-electronic method, capable of sampling the scene to be imaged without the need for a mechanical scan or active circuit components. In order to optimize the imaging characteristics, such as imaging resolution and fidelity ... Full text Cite

Single-frequency near-field MIMO imaging

Conference 2017 11th European Conference on Antennas and Propagation Eucap 2017 · May 15, 2017 A near-field radar imaging technique is presented based on single-frequency measurements from a multiple-input multiple-output (MIMO) array. Such arrays are able to fully sample the κ-space of a region of interest. Advantageously, both range and cross-rang ... Full text Cite

Optimisation of millimetre wave amplifiers for satellite based radiometer

Conference Proceedings of IEEE 9th Uk Europe China Workshop on Millimetre Waves and Terahertz Technologies Ucmmt 2016 · March 7, 2017 STFC / RAL Space has been involved in the development of an extensive variety of satellite mission payloads operating across a wide range of the electromagnetic spectrum. The RAL Space Millimetre-wave Technology Group (MMTG) has undertaken the development ... Full text Cite

Development of transparent patch antenna element integrated with solar cells for Ku-band satellite applications

Conference 2016 Loughborough Antennas and Propagation Conference Lapc 2016 · January 5, 2017 In this paper, a design of broadband compact microstrip meshed patch antenna integrated with solar cells for Ku-band satellite applications is presented. A Plexiglas transparent substrate is also employed to enable the light to pass through with high effic ... Full text Cite

Multispectral metasurface absorbers for optoelectronic devices

Conference Optics Infobase Conference Papers · January 1, 2017 We demonstrate multispectral metasurfaces over wafer-scale areas exhibiting greater than 85 percent absorption, ~100 nm linewidths from 580-1125 nm by patterning plasmonic resonators in micron-scale pixels using a fusion of bottom-up and top-down fabricati ... Full text Cite

Security screening via computational imaging using frequency-diverse metasurface apertures

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2017 Computational imaging is a proven strategy for obtaining high-quality images with fast acquisition rates and simpler hardware. Metasurfaces provide exquisite control over electromagnetic fields, enabling the radiated field to be molded into unique patterns ... Full text Cite

Alternative synthetic aperture radar (SAR) modalities using a 1D dynamic metasurface antenna

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2017 Synthetic aperture radar (SAR) systems conventionally rely on mechanically-Actuated reflector dishes or large phased arrays for generating steerable directive beams. While these systems have yielded high-resolution images, the hardware suffers from conside ... Full text Cite

Reconfigurable metasurface aperture for security screening and microwave imaging

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2017 Microwave imaging systems have seen growing interest in recent decades for applications ranging from security screening to space/earth observation. However, hardware architectures commonly used for this purpose have not seen drastic changes. With the adven ... Full text Cite

Adapting range migration techniques for imaging with metasurface antennas: Analysis and limitations

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2017 Dynamic metasurface antennas are planar structures that exhibit remarkable capabilities in controlling electromagnetic wave-fronts, advantages which are particularly attractive for microwave imaging. These antennas exhibit strong frequency dispersion and p ... Full text Cite

Field repeatability in frequency diverse imaging

Conference 2016 IEEE Antennas and Propagation Society International Symposium Apsursi 2016 Proceedings · October 25, 2016 We consider multi-static imaging systems composed of frequency-diverse transmitting antenna arrays (or apertures). In these frequency diverse imaging modalities, accurate near-field characterization of the antennas is vital to achieving imaging. It is show ... Full text Cite

Metallization of a 3D printed cavitiy for imaging

Conference 2016 IEEE Antennas and Propagation Society International Symposium Apsursi 2016 Proceedings · October 25, 2016 In this paper, we propose a metallized 3D printed cavity for K-band imaging and investigate the effect of metallization type on mode diversity and image reconstruction. The 3D printed cavity acts as a frequency-diverse aperture and is capable of imaging ob ... Full text Cite

Discrete dipole approximation for the simulation of the edge effects on metasurfaces

Conference 2016 IEEE Antennas and Propagation Society International Symposium Apsursi 2016 Proceedings · October 25, 2016 A dipole-based simulation method is presented to study the effects of edges on finite metasurfaces. This technique can accurately account for the physical limitations associated with fabrication and thereby leads to high fidelity predictions needed in prac ... Full text Cite

Toward a tunable mode-mixing cavity for computational imaging

Conference 2016 IEEE Antennas and Propagation Society International Symposium Apsursi 2016 Proceedings · October 25, 2016 A mode-mixing cavity, consisting of an electrically-large rectangular cavity with one deformed corner, supports distinct modes as a function of driving frequency. Perforating one side of this cavity, the modes formed within can be projected into an imaging ... Full text Cite

Additive manufacturing of waveguide for Ku-band satellite communications antenna

Conference 2016 10th European Conference on Antennas and Propagation Eucap 2016 · May 31, 2016 A metal waveguide feed chain in a Ku-band scanning lens array antenna comprises 5 parts. These are: two iris polarisers, two bend-feeds, and a central power combiner. The combiner comprises a pair of septum polarisers and tee junctions. The feed chain gene ... Full text Cite

Electro-optic and radiation damage performance of the CIS115, an imaging sensor for the JANUS optical camera onboard JUICE

Conference Proceedings of SPIE the International Society for Optical Engineering · January 1, 2016 The Jupiter Icy Moon Explorer (JUICE) has been officially adopted as the next Large class mission by the European Space Agency, with a launch date of 2022. The science payload includes an optical camera, JANUS, which will perform imaging and mapping observ ... Full text Cite

Unification of compressed imaging techniques in the microwave range and deconvolution strategy

Conference 2015 European Radar Conference Eurad 2015 Proceedings · December 2, 2015 In recent years, several techniques of imaging have emerged based on compressive sensing. Thus, using passive devices able to code and sum the information measured on a radiating aperture, complex UWB beamforming hardwares can be replaced by inverse proble ... Full text Cite

Directional plasmonic nanoantennas to enhance the purcell effect

Conference 2015 Usnc Ursi Radio Science Meeting Joint with AP S Symposium Usnc Ursi 2015 Proceedings · October 21, 2015 We will present plasmonic nanoantennas, composed of silver nanocubes strongly coupled to gold films, which are the optical and infrared (IR) frequency counterparts to the well-established patch antennas used in microwave frequencies for mobile communicatio ... Full text Cite

Probe configuration study for the metamaterial aperture imager

Conference 2015 9th European Conference on Antennas and Propagation Eucap 2015 · August 27, 2015 We investigate a metamaterial imager (metaimager) consisting of one transmitting metamaterial panel and a collection of broadband receiving probes. Image reconstruction is performed by interrogating a scene with a set of radiative measurement modes encoded ... Cite

Comparison of different reconstruction algorithms for image reconstruction in metamaterial aperture based imaging system

Conference 2015 9th European Conference on Antennas and Propagation Eucap 2015 · August 27, 2015 We investigate the performance of various image reconstruction algorithms for the design of a metamaterial aperture-based imaging system. The metamaterial imaging system consists of a transmitting metamaterial aperture panel and a receiving low-gain probe ... Cite

Plasmonic nanopatch antennas for large purcell enhancement

Conference Conference on Lasers and Electro Optics Europe Technical Digest · August 10, 2015 We demonstrate Purcell enhancements of-1000 from fluorescent molecules embedded in a plasmonic antenna with sub-10 nm gap between metals. Simulations and experiments reveal the high radiative efficiency and directionality of the antenna. ... Cite

Large and ultrafast nonlinear absorption of an air/gold plasmonic waveguide

Conference Conference on Lasers and Electro Optics Europe Technical Digest · August 10, 2015 We investigate theoretically and experimentally the nonlinear propagation of surface plasmons on an air/gold interface which reveals large and ultrafast (∼100 fs) self-induced absorption. The experiment enables a direct measurement of the third-order nonli ... Cite

Scaling of the nonlinear response of metal/dielectric plasmonic waveguides

Conference Conference on Lasers and Electro Optics Europe Technical Digest · August 10, 2015 The scaling of the nonlinear response of a single-interface plasmonic waveguide is studied, where both the metal and dielectric display nonlinearity. We introduce a figure-of-merit that guides metal/dielectric nanophotonic device design for specific applic ... Cite

Analytic modeling of metmaterial absorbers

Conference Conference on Lasers and Electro Optics Europe Technical Digest · August 10, 2015 We present a fully analytical model that describes ideal absorbing metasurfaces composed of film-coupled optical nanoantennas. The model predicts the spectrum and the angular dependence of the absorption and is compared to full-wave numerical simulations. ... Cite

Studying the interplay of electric and magnetic resonance-enhanced second harmonic generation: Theory and experiments

Conference Conference on Lasers and Electro Optics Europe Technical Digest · August 10, 2015 We present an experimental study of a metasurface, which exhibits electric and magnetic resonances, in order to understand their independent contributions to second-harmonic generation. A hydrodynamic model framework is used to match experimental results. ... Cite

Reduced height Luneburg lens antennas for satellite communications-on-the-move

Conference Proceedings of 14th Conference on Microwave Techniques Comite 2015 · June 9, 2015 The hemispherical (or half-Luneburg) lens antenna is a candidate type for satellite communications-on-the-move, either singly or as an element in a small array. It offers good aperture efficiency in a reduced height and excellent scanning performance. This ... Full text Cite

Scaling of the nonlinear response of metal/dielectric plasmonic waveguides

Conference CLEO QELS Fundamental Science CLEO QELS 2015 · May 4, 2015 The scaling of the nonlinear response of a single-interface plasmonic waveguide is studied, where both the metal and dielectric display nonlinearity. We introduce a figure-of-merit that guides metal/dielectric nanophotonic device design for specific applic ... Full text Cite

Plasmonic nanopatch antennas for large purcell enhancement

Conference CLEO QELS Fundamental Science CLEO QELS 2015 · May 4, 2015 We demonstrate Purcell enhancements of ~1000 from fluorescent molecules embedded in a plasmonic antenna with sub-10 nm gap between metals. Simulations and experiments reveal the high radiative efficiency and directionality of the antenna. © OSA 2015. ... Full text Cite

Analytic modeling of metmaterial absorbers

Conference CLEO QELS Fundamental Science CLEO QELS 2015 · May 4, 2015 We present a fully analytical model that describes ideal absorbing metasurfaces composed of film-coupled optical nanoantennas. The model predicts the spectrum and the angular dependence of the absorption and is compared to full-wave numerical simulations. ... Full text Cite

Studying the interplay of electric and magnetic resonance- enhanced second harmonic generation: Theory and experiments

Conference CLEO QELS Fundamental Science CLEO QELS 2015 · May 4, 2015 We present an experimental study of a metasurface, which exhibits electric and magnetic resonances, in order to understand their independent contributions to second-harmonic generation. A hydrodynamic model framework is used to match experimental results. ... Full text Cite

Large and ultrafast nonlinear absorption of an air/gold plasmonic waveguide

Conference CLEO QELS Fundamental Science CLEO QELS 2015 · May 4, 2015 We investigate theoretically and experimentally the nonlinear propagation of surface plasmons on an air/gold interface which reveals large and ultrafast (~100 fs) self-induced absorption. The experiment enables a direct measurement of the third-order nonli ... Full text Cite

Microwave inverse scattering using scalar indirect holographic techniques

Conference Mediterranean Microwave Symposium · April 17, 2015 This paper describes the use of indirect microwave holographic together with inverse scattering techniques for the reconstruction of the dielectric properties of unknown objects. The use of indirect microwave holography enables the complex field scattered ... Full text Cite

The development of indirect microwave holography for measurement and imaging applications

Conference Mediterranean Microwave Symposium · January 7, 2015 This work describes the development of indirect holographic techniques for microwave measurements and imaging. It outlines the basic theory of indirect holography and how it relates to optical holographic techniques. It starts with a description of the ini ... Full text Cite

Nonlinear Metal/Dielectric Plasmonic Interfaces

Conference Nonlinear Optics Nlo 2015 · January 1, 2015 We investigate theoretically and experimentally the optical nonlinearity of metal/dielectric interfaces, which provides a metric that predicts the scaling of self-action as well as a means to measure χ(3)of gold using surface plasmon polaritons. ... Full text Cite

Metamaterial resonators for dynamic spatial millimeter-wave modulators

Conference Proceedings of Frontiers in Optics 2015, FIO 2015 · January 1, 2015 © OSA 2015. Many phase spatial modulators exist at optical frequencies such as liquid crystal cells. We present an alternative for millimeter-waves based on metamaterial resonators that produces strong phase modulation from a small tuning range. ... Cite

Monitoring WLCG with lambda-architecture: A new scalable data store and analytics platform for monitoring at petabyte scale.

Conference Journal of Physics Conference Series · January 1, 2015 Monitoring the WLCG infrastructure requires the gathering and analysis of a high volume of heterogeneous data (e.g. data transfers, job monitoring, site tests) coming from different services and experiment-specific frameworks to provide a uniform and flexi ... Full text Cite

Stabilization of electron-scale turbulence by electron density gradient in NSTX

Conference 42nd European Physical Society Conference on Plasma Physics Eps 2015 · January 1, 2015 Cite

Inter-ELM pedestal evolution and the role of edge fluctuations in the C-Mod and DIII-D tokamaks

Conference 42nd European Physical Society Conference on Plasma Physics Eps 2015 · January 1, 2015 Cite

Giant fluorescence enhancement of molecules coupled to plasmonic nanoscale patch antennas

Conference Frontiers in Optics, FiO 2014 · October 14, 2014 © OSA 2014. We demonstrate a colloidally synthesized and tunable plasmonic platform for giant fluorescence enhancement and increased spontaneous emission rate of embedded fluorophores. A transition between fluorescence enhancement and quenching is revealed ... Cite

Second harmonic generation by metamagnetics: Interplay of electric and magnetic resonances

Conference Frontiers in Optics, FiO 2014 · October 14, 2014 © OSA 2014. We present the first experimental study of the interplay of electric and magnetic resonances in a metamaterial to measure their independent contributions to second-harmonic generation. Experiments indicate evident contribution to SHG from funda ... Cite

Comparison of different combining methods for space-diversity FSO systems

Conference 2014 9th International Symposium on Communication Systems Networks and Digital Signal Processing Csndsp 2014 · October 14, 2014 This paper gives an overview of different signal combining schemes for free space optical (FSO) communication systems employing spatial diversity (SD) for the case of lognormal weak turbulence atmospheric channels. The receiver configurations are explained ... Full text Cite

Ultrafast self-action in an air/gold plasmonic waveguide

Conference Optics InfoBase Conference Papers · July 21, 2014 Cite

Analysis and modeling of metamaterial absorbers

Conference Optics InfoBase Conference Papers · July 21, 2014 Cite

Ultrafast self-action in an air/gold plasmonic waveguide

Conference Optics InfoBase Conference Papers · July 21, 2014 Cite

Analysis and modeling of metamaterial absorbers

Conference Optics InfoBase Conference Papers · July 21, 2014 Cite

Tunable plasmonic platform for giant fluorescence enhancement

Conference Optics InfoBase Conference Papers · January 1, 2014 We demonstrate a colloidally synthesized plasmonic platform for giant fluorescence enhancement and increased spontaneous emission rate of embedded fluorophores. A transition between fluorescence enhancement and quenching is revealed depending on the plasmo ... Cite

Tunable plasmonic platform for giant fluorescence enhancement

Conference Conference on Lasers and Electro Optics Europe Technical Digest · January 1, 2014 We demonstrate a colloidally synthesized plasmonic platform for giant fluorescence enhancement and increased spontaneous emission rate of embedded fluorophores. A transition between fluorescence enhancement and quenching is revealed depending on the plasmo ... Cite

A transparent meshed solar monopole antenna for UWB applications

Conference 8th European Conference on Antennas and Propagation Eucap 2014 · January 1, 2014 This paper demonstrates the integration of a transparent meshed circular monopole antenna with a polycrystalline silicon (poly-Si) solar cell operating as an RF ground plane in addition to its photovoltaic function. While the meshed circular monopole with ... Full text Cite

A dual-polarized solar cell stacked microstrip patch antenna with a λ/4 DC/RF isolation circuit for 5.8 GHz band WiMAX networks

Conference 8th European Conference on Antennas and Propagation Eucap 2014 · January 1, 2014 In this paper, photovoltaic integration of a dual-polarized microstrip patch antenna is demonstrated for 5.8 GHz band WiMAX networks. The proposed antenna consists of a dual-fed ±45° dual-polarized square microstrip patch stacked with a polycrystalline sil ... Full text Cite

An outline of indirect holographic methods for antenna measurements and microwave imaging

Conference 2014 24th International Conference Radioelektronika Radioelektronika 2014 Proceedings · January 1, 2014 Indirect microwave holographic techniques offer a simple, low cost technique for a range of microwave measurements including the determination of antenna characteristics and the ability to provide good quality images of passive objects. This work provides ... Full text Cite

Characterisation of an RF excited argon plasma cathode electron beam gun

Conference 2014 10th International Vacuum Electron Sources Conference Ivesc 2014 and 2nd International Conference on Emission Electronics Icee 2014 Proceedings · January 1, 2014 This work describes the experimental set up used for carrying out spectroscopic measurements in a plasma cathode electron beam (EB) gun. Advantages of plasma cathode guns over thermionic guns are described. The factors affecting electron beam power such as ... Full text Cite

Spectroscopic characterization of a novel RF excited plasma cathode electron beam gun design

Conference IEEE International Vacuum Electronics Conference Ivec 2014 · January 1, 2014 This work presents a radio frequency (RF) excited electron beam (EB) gun design and experimental results obtained at a frequency of 84 MHz. Details of the design features of the plasma device are given and advantages over thermionic cathode triode EB guns ... Full text Cite

Simulations of 2D metamaterial apertures for coherent computational imaging

Conference 2013 IEEE International Conference on Microwaves Communications Antennas and Electronic Systems Comcas 2013 · December 1, 2013 A metamaterial aperture operating as a leaky waveguide with resonating metamaterial irises can sweep its operation frequency to modify its complex field pattern with no moving parts. By randomly distributing the metamaterials' resonance frequencies, we sho ... Full text Cite

Solar cell stacked modified Z-double L-slot quad-band PIFA

Conference 2013 7th European Conference on Antennas and Propagation Eucap 2013 · August 14, 2013 This paper proposes a novel low-profile quad-band multifunctional solar PIFA consisting of a polycrystalline silicon (poly-Si) solar cell stacked suspended modified radiating element with Z and double L-slots. The measured return loss (S11) and E-plane/H-p ... Cite

The use of indirect holographic techniques for microwave imaging

Conference Proceedings of 13th Conference on Microwave Techniques Comite 2013 Marew 2013 Microwave and Radio Electronics Week 2013 · August 12, 2013 The use of indirect holographic techniques for antenna testing has been shown to offer a simple, low cost scalar technique for the reconstruction of complex antenna aperture fields. This work extends the use of indirect holography to the imaging of objects ... Full text Cite

Cross-coax fed wideband solar patch antenna

Conference Proceedings of 13th Conference on Microwave Techniques Comite 2013 Marew 2013 Microwave and Radio Electronics Week 2013 · August 12, 2013 In this paper, a cross-coax fed low-profile short-circuited suspended patch antenna combined with a polycrystalline silicon (poly-Si) solar cell operating as a radiating patch element is proposed for self-powered 2.4 GHz band WLAN and 2.3/2.5 GHz band WiMA ... Full text Cite

Investigations of resolution limits for indirect microwave holographic imaging

Conference International Journal of RF and Microwave Computer Aided Engineering · July 1, 2013 This work describes how indirect holography which has previously been applied to the determination of antenna radiation patterns can be adapted for the imaging of passive objects. It provides details of how complex scattered field values can be obtained in ... Full text Cite

A report on H-FSO/RF antenna measurement for outdoor applications

Conference Proceedings of the 2013 2nd International Workshop on Optical Wireless Communications Iwow 2013 · January 1, 2013 This paper presents a report on experimental set up and results for a hybrid free space optics (FSO)/radio frequency (RF) dual purpose antenna for outdoor applications. The basic design of the antenna is discussed and we present two sets of early experimen ... Full text Cite

On-orbit results for the xilinx virtex-4 FPGA

Conference IEEE Radiation Effects Data Workshop · December 11, 2012 This paper provides information regarding the use of the Xilinx Virtex-4 field-programmable gate array in a spacecraft deployed to low-earth orbit. The results are compared to pre-deployment accelerated and fault-injection testing. Copyright © 2012 by the ... Full text Cite

Design of a highly efficient wideband suspended solar array antenna

Conference IEEE Antennas and Propagation Society AP S International Symposium Digest · December 10, 2012 This paper presents the design of a wideband suspended solar patch array antenna for WLAN and ISM band applications. The suspended silicon solar cells, which have been replaced with traditional microstrip patches and work as antennas within the design, are ... Full text Cite

A triband short-circuited suspended solar patch antenna

Conference 2012 10th International Symposium on Antennas Propagation and EM Theory Isape 2012 · December 1, 2012 In this paper, a triband low-profile short-circuited suspended patch antenna combined with a polycrystalline silicon solar cell working as a radiating patch element is proposed for 2.3/2.5/2.8/3.3/3.5 GHz band WiMAX and 2.4 GHz band WLAN networks. The fabr ... Full text Cite

Symmetric/asymmetric H-plane horn fed offset parabolic reflector antenna with switchable pencil/fan-beam radiation characteristics

Conference 2012 10th International Symposium on Antennas Propagation and EM Theory Isape 2012 · December 1, 2012 This paper presents a modified offset parabolic reflector antenna design with easily switchable pencil/fan-beam radiation patterns for X-band tracking, scanning and surveillance microwave radar systems. The modified offset parabolic reflector antenna, comb ... Full text Cite

A meshed multiband solar patch array antenna

Conference Lapc 2012 2012 Loughborough Antennas and Propagation Conference · December 1, 2012 In this paper, a meshed multiband solar patch array antenna, consisting of a polycrystalline silicon solar panel working as a ground plane whilst generating a DC power output of 1.48 W as a result of the photovoltaic effect with a measured solar efficiency ... Full text Cite

Effect of gamma radiation on potential ionising radiation detectors and dosimeters based on quantum dots

Conference IEEE Nuclear Science Symposium Conference Record · December 1, 2012 In this work, we report measured effects on the fluorescent emission spectra of commercially produced core-shell (CdSe/ZnS) quantum dots (QDs) of 2.5 nm, 3.3 nm and 6.3 nm size in toluene, following exposure to 1 MeV gamma irradiation in the range 0.1-110 ... Full text Cite

Development of a laboratory based XRF facility for measuring elemental abundance ratios in planetary analogue powder samples

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2012 This paper describes the use of a swept-charge device (SCD) silicon X-ray detector in a laboratory based X-ray fluorescence (XRF) facility for calculating elemental abundance ratios from planetary analogue powder samples. The facility was developed to supp ... Full text Cite

The effects of radiation damage on the spectral resolution of the Chandrayaan-1 X-ray Spectrometer over the full mission duration

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2012 The Chandrayaan-1 X-ray Spectrometer (C1XS) was launched onboard the Indian Space Research Organisation (ISRO) Chandrayaan-1 lunar mission in October 2008. The instrument consisted of 24 swept-charge device silicon X-ray detectors providing a total collect ... Full text Cite

Development of an ionising radiation detector based on quantum dots absorbed in porous glass

Conference Proceedings of the IEEE Conference on Nanotechnology · November 22, 2012 In this work, we report measured effects on the fluorescent emission spectra of commercially produced core-shell (CdSe/ZnS) quantum dots (QDs). We report the effects on the fluorescent emission spectra of commercially produced CdSe/ZnS QDs of 2.5 nm, 3.3 n ... Full text Cite

Modelling and analysis of a smart antenna system with sub-sector dynamic capacity enhancement for mobile telecommunication networks

Conference Proceedings of the 2012 8th International Symposium on Communication Systems Networks and Digital Signal Processing Csndsp 2012 · November 12, 2012 This paper describes the modelling and analysis of a new smart antenna concept. The paper outlines the rational for the development of a dynamically reconfigurable smart antenna system without greatly increasing the complexity of the system. The subject sm ... Full text Cite

A solar parabolic reflector antenna design for digital satellite communication systems

Conference Proceedings of the 2012 8th International Symposium on Communication Systems Networks and Digital Signal Processing Csndsp 2012 · November 12, 2012 This paper introduces a compact solar parabolic reflector antenna design, with an effective DC solar performance and high gain / pencil beam antenna radiation characteristics, as an alternative to the standalone use of home-based autonomous solar panels an ... Full text Cite

Diagnostic performance of the beam emission spectroscopy system on the National Spherical Torus Experiment

Conference Review of Scientific Instruments · October 1, 2012 The beam emission spectroscopy system on the National Spherical Torus Experiment measures localized density fluctuations on the ion gyroscale. Optical sightlines provide core to edge radial coverage, and the sightlines are aligned to typical pitch angles t ... Full text Cite

A modified holographic technique for cylindrical near-field antenna measurements

Conference Proceedings of 6th European Conference on Antennas and Propagation Eucap 2012 · July 2, 2012 A modification of the synthetic-cylindrical-wave-based holographic technique for determining radiation patterns and aperture fields of antennas is proposed. The modification is based on using both the sum and difference of the near field and reference sign ... Full text Cite

The use of swept-charge devices in planetary analogue X-ray fluorescence studies

Conference Journal of Instrumentation · July 1, 2012 The Chandrayaan-1 X-ray Spectrometer (C1XS) was launched onboard the Indian Space Research Organisation (ISRO) Chandrayaan-1 lunar mission in October 2008. The instrument consisted of 24 swept-charge device (SCD) silicon X-ray detectors providing a total c ... Full text Cite

Design of a highly efficient beam scanning asymmetric H-plane horn antenna

Conference 2012 IEEE International Workshop on Antenna Technology Iwat 2012 · May 11, 2012 This paper presents the design and results of a novel asymmetric H-plane horn antenna with an easily scanable, highly efficient asymmetric radiation pattern. This design offers a cost-effective and practical alternative to the current beam scanning horn an ... Full text Cite

A smart antenna system with sub-sector dynamic capacity enhancement for mobile telecommunication networks

Conference 2012 IEEE International Workshop on Antenna Technology Iwat 2012 · May 11, 2012 Dynamic concentration of the users within a part of a cell sector has placed pressure on network operators to find ways to dynamically optimise the sector to increase capacity and quality of service while maintaining coverage. Smart antenna systems have be ... Full text Cite

The Chandrayaan-1 X-ray Spectrometer: First results

Conference Planetary and Space Science · January 1, 2012 We present X-ray fluorescence observations of the lunar surface, made by the Chandrayaan-1 X-ray Spectrometer during two solar flare events early in the mission (12th December 2008 and 10th January 2009). Modelling of the X-ray spectra with an abundance al ... Full text Cite

Effect of gamma radiation on potential ionising radiation detectors and dosimeters based on quantum dots

Conference IEEE Nuclear Science Symposium Conference Record · January 1, 2011 The fluorescent quantum yield of core-shell (CdSe/ZnS) quantum dots (QDs) in hexane has recently been shown to decrease with increasing gamma irradiation dose. Here we report the effects on the fluorescent emission spectra of commercially produced CdSe/ZnS ... Full text Cite

The use of indirect holographic techniques for microwave imaging

Conference 2010 10th Mediterranean Microwave Symposium Mms 2010 · December 20, 2010 This work provides a brief outline of the basic theory of indirect microwave holography. This is supported by experimental work which illustrates how this technique can be used successfully in a number of areas including antenna measurements, concealed wea ... Full text Cite

A low profile radiating element with nearly hemispheric coverage for satellite communications on-the-move hybrid array antenna

Conference 2010 7th International Symposium on Communication Systems Networks and Digital Signal Processing Csndsp 2010 · November 12, 2010 A novel design solution of a dual-linearly-polarised Ku-band low-profile radiating element for low elevation angle coverage (down to 10° above horizon) is presented. Such an element is suitable for full-duplex Satellite Communications On-The-Move (SCOTM) h ... Cite

Overview of the beam emission spectroscopy diagnostic system on the National Spherical Torus Experiment

Conference Review of Scientific Instruments · October 1, 2010 A beam emission spectroscopy (BES) system has been installed on the National Spherical Torus Experiment (NSTX) to study ion gyroscale fluctuations. The BES system measures Dα emission from a deuterium neutral heating beam. The system includes tw ... Full text Cite

Low-noise, high-speed detector development for optical turbulence fluctuation measurements for NSTX

Conference Review of Scientific Instruments · October 1, 2010 A new beam emission spectroscopy (BES) diagnostic is under development. Photon-noise limited measurements of neutral beam emissions are achieved using photoconductive photodiodes with a novel frequency-compensated broadband preamplifier. The new BES system ... Full text Cite

Ultrafast spectroscopy diagnostic to measure localized ion temperature and toroidal velocity fluctuations

Conference Review of Scientific Instruments · October 1, 2010 A dual-channel high-efficiency, high-throughput custom spectroscopic system has been designed and implemented at DIII-D to measure localized ion thermal fluctuations associated with drift wave turbulence. A large-area prism-coupled transmission grating and ... Full text Cite

The effects of radiation damage on the spectral resolution of the Chandrayaan-1 x-ray spectrometer

Conference Proceedings of SPIE the International Society for Optical Engineering · September 7, 2010 The Chandrayaan-1 X-ray Spectrometer (C1XS) was launched onboard the Indian Space Research Organisation (ISRO) Chandrayaan-1 lunar mission in October 2008. The instrument consisted of 24 swept-charge device silicon X-ray detectors providing a total collect ... Full text Cite

Fundamental issues in antenna design for microwave medical imaging applications

Conference 2010 7th International Symposium on Communication Systems Networks and Digital Signal Processing Csndsp 2010 · January 1, 2010 This paper surveys the development of microwave medical imaging and the fundamental challenges associated with microwave antennas design for medical imaging applications. Different microwave antennas used in medical imaging applications such as monopoles, ... Full text Cite

A Novel simplified mathematical model for antennas used in medical imaging applications

Conference Journal of Physics Conference Series · January 1, 2010 In this paper a new technique is proposed to model the current across a monopole antenna and thereby the radiation fields of the antenna can be calculated. Generally, the Method of Moments (MOM) technique is used for this purpose whereby the integral equat ... Full text Cite

The effects of a finite ground plane on the characteristics of printed patch antennas with and without a suspended patch

Conference 2010 7th International Symposium on Communication Systems, Networks and Digital Signal Processing, CSNDSP 2010 · January 1, 2010 In most analyses of microstrip patch antennas the effects of a finite ground plane are neglected because it is assumed infinite. However, in mobile communication systems the ground plane of antennas must be finite. Therefore, the effect of the finite groun ... Full text Cite

Simulation of MeV electron energy deposition in CdS quantum dots absorbed in silicate glass for radiation dosimetry

Conference Journal of Physics Conference Series · January 1, 2010 We are currently developing 2D dosimeters with optical readout based on CdS or CdS/CdSe core-shell quantum-dots using commercially available materials. In order to understand the limitations on the measurement of a 2D radiation profile the 3D deposited ene ... Full text Cite

Calibration of the collective scattering system on NSTX

Conference 34th International Conference on Infrared Millimeter and Terahertz Waves Irmmw Thz 2009 · December 31, 2009 A multichannel 280-GHz collective scattering system has been employed to investigate electron gyro-scale density fluctuations in National Spherical Torus Experiment (NSTX) plasmas. The longitudinal scattering volume length, which is the spatial resolution ... Full text Cite

A new low profile antenna with improved performance for satellite on-the-move communications

Conference Proceedings 2009 3rd IEEE International Symposium on Microwave Antenna Propagation and EMC Technologies for Wireless Communications Mape 2009 · December 1, 2009 A novel design solution for a low-profile full-duplex Satellite-On-The-Move Communications hybrid scanned phased array antenna for low elevation angle coverage (down to 10° ) is described. The antenna is operated at Ku-Band. The unique louvered array eleme ... Full text Cite

Internal transport barriers in the National Spherical Torus Experiment

Conference Physics of Plasmas · June 10, 2009 In the National Spherical Torus Experiment [M. Ono, Nucl. Fusion 41, 1435 (2001)], internal transport barriers (ITBs) are observed in reversed (negative) shear discharges where diffusivities for electron and ion thermal channels and momentum are reduced. W ... Full text Cite

A modified holographic technique for antenna measurements

Conference Isape 2008 the 8th International Symposium on Antennas Propagation and EM Theory Proceedings · December 1, 2008 This work describes an extension to the use of indirect holographic techniques for antenna measurements. Previous versions of this work have been restricted to the measurement of high gain antennas without reducing sample spacing and increasing measurement ... Full text Cite

A multiple switched beam smart antenna with beam shaping for dynamic optimisation of capacity & coverage in mobile telecommunication networks

Conference Isape 2008 the 8th International Symposium on Antennas Propagation and EM Theory Proceedings · December 1, 2008 A four column Smart antenna array fed by a 4×4 Butler matrix augmented by a variable beam shaping network has been designed and simulated. It is demonstrated that using only three phase shifters within the beam shaping network provides dynamic beam flexibi ... Full text Cite

Radiation study of swept-charge devices for the Chandrayaan-1 X-ray spectrometer (C1XS) instrument

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2008 The Chandrayaan-1 X-ray Spectrometer (C1XS) will be launched as part of the Indian Space Research Organisation (ISRO) Chandrayaan-1 payload in September 2008, arriving at the Moon within 7 days to begin a two year mission in lunar orbit conducting mineralo ... Full text Cite

Imaging and spectroscopy using a scintillator-coupled EMCCD

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2008 The CCD97 is a low light level (L3) device from e2v technologies range of electron multiplying CCDs (EMCCDs). The device uses e2v's patented extended gain register and through the use of appropriately designed electrodes can be used to maximise the signal ... Full text Cite

Production of BABAR skimmed analysis datasets using the grid

Conference Journal of Physics Conference Series · July 1, 2008 The BABAR Collaboration, based at Stanford Linear Accelerator Center (SLAC), Stanford, US, has been performing physics reconstruction, simulation studies and data analysis for 8 years using a number of compute farms around the world. ... Full text Cite

An improved holographic technique for medium-gain antenna near field measurements

Conference Iet Seminar Digest · December 1, 2007 A modification of the holographic technique based on synthetic plane wave for determining radiation patterns and aperture fields of medium-gain horn antennas is proposed. The modification is based on using both the sum and difference of the near field and ... Full text Cite

Initial results on X-polar far-field radiation patterns prediction using indirect holographic measurements

Conference IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) · December 1, 2007 Full text Cite

A modified holographic technique for antenna measurements

Conference 2007 International Conference on Electromagnetics in Advanced Applications, ICEAA'07 · December 1, 2007 A modification of the synthetic-plane-wave-based holographic technique for determining radiation patterns and aperture fields of medium-gain horn antennas is proposed. The modification is based on using both the sum and difference of the near field and ref ... Full text Cite

Characterisation of swept-charge devices for the Chandrayaan-1 X-ray Spectrometer (C1XS) instrument

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2007 The Indian Space Research Organisation (ISRO) Chandrayaan-1 mission is India's first lunar spacecraft, containing a suite of instruments to carry out high-resolution remote sensing of the Moon at visible, near infrared and X-ray wavelengths. Due for launch ... Full text Cite

Microwave holographic imaging technique for tumour detection

Conference Ifmbe Proceedings · January 1, 2007 Early, accurate and efficient screening of tumour will go a long way to improve the life expectancy and quality of life. Microwave holographic technique uses nonionising radiation which has the potential to screen patients for tumour at low cost. It offers ... Full text Cite

Microwave holographic imaging of breast cancer

Conference IEEE 2007 International Symposium on Microwave Antenna Propagation and EMC Technologies for Wireless Communications Mape · January 1, 2007 Breast cancer is one of the most common forms of cancer in women. X-ray mammography is the most widely used technique for early detection but has limitations. In this paper, an alternative approach for breast cancer detection using microwave imaging is pre ... Full text Cite

3D Microwave imaging for medical and security applications

Conference 2006 International RF and Microwave Conference, (RFM) Proceedings · December 1, 2006 The use of microwaves for imaging applications is currently of much research interest particularly in the areas of security imaging and medical imaging. Microwaves have been shown to be able to image objects concealed beneath clothing and recent research w ... Full text Cite

EMCCDs for space applications

Conference Proceedings of SPIE the International Society for Optical Engineering · October 17, 2006 This paper describes a qualification programme for Electron-Multiplication Charge Coupled Devices (EMCCDs) for use in space applications. While the presented results are generally applicable, the programme was carried out in the context of CCD development ... Full text Cite

Preliminary results from herschel-SPIRE flight instrument testing

Conference Proceedings of SPIE the International Society for Optical Engineering · October 2, 2006 The Spectral and Photometric Imaging REceiver (SPIRE) is one of the three scientific instruments to fly on the European Space Agency's Herschel Space Observatory, and contains a three-band imaging submillimetre photometer and an imaging Fourier transform s ... Full text Cite

A microwave indirect holographic system for security and medical imaging applications

Conference European Space Agency Special Publication ESA SP · October 1, 2006 This work details how an indirect microwave holographic technique originally developed for antenna measurements can be extended to imaging applications. It outlines how complex field patterns can be reconstructed from holographic intensity patterns. It als ... Cite

Early stage breast cancer detection using indirect microwave holography

Conference Proceedings of the 36th European Microwave Conference Eumc 2006 · January 1, 2006 A novel microwave imaging approach for early stage breast cancer detection is described. The proposed technique involves the use of an Indirect Microwave Holographic technique employing a patented synthetic reference wave. This approach offers benefits in ... Full text Cite

Imaging of dielectric objects from phase patterns reconstructed using indirect holographic intensity patterns

Conference Iceaa 2005 9th International Conference on Electromagnetics in Advanced Applications and Eesc 2005 11th European Electromagnetic Structures Conference · December 1, 2005 This work provides a discussion of a technique developed at Northumbria University that enables full 3D object images to be recorded in a 2D intensity pattern, by utilizing the holographic principle originally developed as an optical technique. ... Cite

Imaging dielectric objects from scalar intensity patterns by means of indirect holography

Conference IEEE Antennas and Propagation Society AP S International Symposium Digest · December 1, 2005 An indirect microwave holographic technique for the reconstruction of complex scattered fields and the imaging of objects from a single holographic intensity pattern is described. The holographic intensity pattern is constructed by combining the signal sca ... Full text Cite

Gaia astrometric CCDs and focal plane

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2005 ESA's Gaia astrometry mission is due for launch in 2011. The astrometric instrument focal plane will have an area of up to 0.5m2 and will contain more than 100 CCDs. These will be operated in Time Delay and Integration mode in order to track and ... Full text Cite

MOS CCDs for the Wide Field Imager on the XEUS Spacecraft

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2005 In recent years the XEUS mission concept has evolved and has been the subject of several industrial studies. The mission concept has now matured to the point that it could be proposed for a Phase A study and subsequent flight programme. The key feature of ... Full text Cite

Application of electron multiplying CCD technology in space instrumentation

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2005 Electron multiplying CCD (EMCCD) technology has found important initial applications in low light surveillance and photon starved scientific instrumentation. This paper discusses the attributes of the EMCCD which make it useful for certain space instrument ... Full text Cite

Mechanical design of the NSTX high-k scattering diagnostic

Conference Proceedings Symposium on Fusion Engineering · January 1, 2005 The NSTX High-k Scattering Diagnostic measures small-scale density fluctuations by the heterodyne detection of waves scattered from a millimeter wave probe beam at 280 GHz and λ=1. 07 mm. To enable this measurement, major alterations were made to the NSTX ... Full text Cite

First results from Herschel-SPIRE performance tests

Conference Proceedings of SPIE the International Society for Optical Engineering · December 20, 2004 The Spectral and Photometric Imaging REceiver (SPIRE) is one of the three scientific instruments on the European Space Agency's Herschel mission. At the start of 2004 the Cryogenic Qualification Model (CQM) of SPIRE was tested with the aim of verifying the ... Full text Cite

High efficiency class-F Power Amplifier design

Conference IEEE High Frequency Postgraduate Student Colloquium · December 1, 2004 In this paper, a high efficiency, low voltage, class-F Power Amplifier (PA) is described. The effect of different output harmonic terminations on the Power-Added Efficiency (PAE) of the PA has also been analysed. A medium power PHEMT PA operating at 900MHz ... Cite

Imaging concealed objects from scalar microwave holograms

Conference 2004 RF and Microwave Conference, RFM 2004 - Proceedings · December 1, 2004 A new technique for the imaging of concealed objects using indirect holographic imaging principles is outlined. A brief examination of the underlying theory followed by a description of the novel experimental system that has been developed to overcome some ... Cite

Low noise charge injection in the CCD22

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2004 The inclusion of a charge injection structure on a charge coupled device (CCD) allows for the mitigation of charge transfer loss which can be caused by radiation induced charge trapping defects. Any traps present in the pixels of the CCD are filled by the ... Full text Cite

Development of the CCDs for ESA's GAIA cornerstone mission

Conference Proceedings of SPIE the International Society for Optical Engineering · May 3, 2004 The ESA cornerstone mission GAIA will perform astrometric and photometric measurements on one billion objects, and is due for launch in 2010 into L2 orbit. The key astrometric focal plane will comprise over 180 large area CCDs with a focal surface of about ... Full text Cite

CCDs for the Radial Velocity Spectrometer on GAIA

Conference Proceedings of SPIE the International Society for Optical Engineering · May 3, 2004 The ESA cornerstone mission GAIA will perform astrometric, photometric and spectroscopic measurements and is due for launch in 2010 into L2 orbit. The astrometric telescope system will catalogue the position of over 109 objects down to 20th ... Full text Cite

Indirect holographic imaging of antennas using an electronically synthesised "slow-wave"

Conference IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) · January 1, 2004 The use of indirect holographic techniques, where radiation characteristics and antenna aperture fields can be obtained from simple intensity measurements made in the near field, has traditionally been restricted to the measurement of large antennas with s ... Full text Cite

3D imaging of antenna fields and metal objects using a new indirect holographic method

Conference Iceaa 2003 International Conference on Electromagnetics in Advanced Applications · December 1, 2003 This work describes a new technique for producing indirect holographic intensity patterns from which antenna far field radiation patterns can be obtained and images of antenna fields can be reconstructed. It also describes how this technique can be extende ... Cite

The effect of protons on E2V Technologies L3Vision CCDs

Conference Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment · November 1, 2003 The effect of different 10 MeV equivalent proton fluences on the performance of E2V Technologies (formerly Marconi applied technologies, formerly EEV) L3Vision Charge Coupled Devices (CCDs) was investigated. The first experimental radiation damage results ... Full text Cite

The prompt particle background and micrometeoroid environment at L2 and its implications for Eddington

Conference European Space Agency Special Publication ESA SP · April 1, 2003 The Eddington spacecraft will orbit the Sun at the L2 point during its 5 year asteroseismology and planet finding mission. The successful detection of objects of interest and the amount and accuracy of the data that is recorded will depend on the prompt pa ... Cite

Surface plasmon coupling between two nano Au particles

Conference Proceedings of the IEEE Conference on Nanotechnology · January 1, 2003 Nano metal particles which interact strongly with visible light make themselves useful for molecular detection and biosensing. To facilitate the useful application for these nano particles, it is important to design and fabricate the particles at a desired ... Full text Cite

Integrated sensing in structural composites

Conference Structural Health Monitoring 2003 from Diagnostics and Prognostics to Structural Health Management Proceedings of the 4th International Workshop on Structural Health Monitoring Iwshm 2003 · January 1, 2003 Increasing demand for monitoring of in-service structures is driving technology in new directions. Advances in many related technologies, including novel sensor design and implementation, have created new opportunities in structural health monitoring. We p ... Cite

3D imaging of antenna fields from electronically synthesised scalar intensity patterns

Conference 2003 Asia Pacific Conference on Applied Electromagnetics Apace 2003 Proceedings · January 1, 2003 This work describes a new technique for the determination of antenna far field radiation patterns and the imaging of antenna fields from holographic intensity patterns. These intensity patterns are obtained by combining the sampled antenna near field with ... Full text Cite

A novel technique for the determination of the radiation patterns of medium gain antennas from scalar intensity measurements

Conference Isape 2003 2003 6th International Symposium on Antennas Propagation and EM Theory Proceedings · January 1, 2003 Holographic techniques have proved useful -for the determination of antenna radiation patterns and imaging antenna fields. Traditionally this has been achieved mainly by the direct measurement of complex near fields of the antenna over a measurement plane ... Full text Cite

The effect of low energy protons on the operational characteristics of EPIC-MOS CCDs

Conference Proceedings of the European Conference on Radiation and Its Effects on Components and Systems RADECS · December 1, 2002 The University of Tubingen 3.5 MeV Van de Graaf accelerator facility was used to investigate the effect of low energy protons on the performance of the European Photon Imaging Camera (EPIC), metal-oxide semiconductor (MOS), charge coupled devices (CCDs). T ... Cite

Proton induced leakage current in CCDs

Conference Proceedings of SPIE the International Society for Optical Engineering · December 1, 2002 The effect of different proton fluences on the performance of two E2V Technologies (formerly Marconi Applied Technologies, formerly EEV) CCD47-20 devices was investigated with particular emphasis given to the analysis of 'Random telegraph signal' (RTS) gen ... Full text Cite

An indirect holographic method for determining antenna radiation patterns and imaging antenna fields

Conference IEEE Antennas and Propagation Society AP S International Symposium Digest · August 5, 2002 This work describes a new technique for the determination of antenna radiation patterns and the imaging of antenna aperture fields. It uses an indirect holographic method to record simple intensity patterns formed by a combination of antenna near field sig ... Cite

Fabrication and characterization of THz plasmonic filter

Conference Proceedings of the IEEE Conference on Nanotechnology · January 1, 2002 Terahertz imaging systems have applications for explosives detection, aircraft guidance and landing in zero-visibility weather condition, as well as terrestrial and astronomical remote sensing. These critical applications need a variety of optical elements ... Full text Cite

Low cost tyre monitoring system using electronic article surveillance techniques

Conference IEE Colloquium Digest · January 1, 1997 A low cost method for tire monitoring is designed using a passive LC circuit tag is used for contactless sensing. Circuit response to bursts of radio frequency pulses is made to vary with changes in tire pressure. Separate transmit and receive antennas are ... Cite

Performance of a novel dual-band horn antenna @ 20/30GHz

Conference 1996 26th European Microwave Conference Eumc 1996 · January 1, 1996 The design for a narrow angle feed horn radiating low levels of cross polarisation in two widely separated frequency bands is presented. The horn uses corrugations to control the cross polarisation in the lower frequency band and a synthesised aperture dis ... Full text Cite

Wide flare-angle horn antenna with means for radiating low levels of crosspolarisation in two widely separated frequency bands

Conference IEEE Antennas and Propagation Society AP S International Symposium Digest · January 1, 1996 Preliminary results for a horn antenna with good crosspolar performance in two discrete frequency bands in addition to desirable VSWR characteristics are presented. The horn combines two different design concepts. It uses corrugations to control the crossp ... Cite

Design, construction and performance of a small, low cost anechoic measuring system for research applications

Conference IEEE Antennas and Propagation Society AP S International Symposium Digest · January 1, 1995 A low cost anechoic measuring system has been designed, constructed and evaluated. It consists of a small anechoic chamber, designed specifically for measurements of high performance feed horns within the range 18-30GHz, and a simple antenna positioner. Th ... Cite

Enhanced teaching of antenna theory and measurement techniques using a low cost anechoic measuring system

Conference 1995 25th European Microwave Conference · January 1, 1995 A low cost anechoic chamber and simple antenna positioner have been constructed. They have been incorporated into a fully automated antenna pattern measuring system which takes advantage of the department's existing network analyser as both the source and ... Full text Cite

Effects of load impedance os the dimensions and beamwidth of a dual feed nearly square patch antenna for circular polarisations

Conference IEEE Antennas and Propagation Society AP S International Symposium Digest · January 1, 1992 Full text Cite

Dual circular polarised microstrip antenna design for a passive microwave transponder

Conference IEE Conference Publication · January 1, 1991 This work has extended the use of a simple cavity model to the case of a dual feed nearly square antenna for circular polarisation. The addition of the second feed is found to alter the conditions required for the generation of circular polarisation and re ... Cite

Dual polarized microstrip antenna design for a polarization shift keying microwave transponder

Conference Conference Proceedings European Microwave Conference · December 1, 1989 This work describes a novel method of data transmission by means of polarization shift keying. It analyzes the system performance in terms of S/N ratio and defines the required antenna cross polarization performance to achieve an acceptable S/N ratio. A th ... Cite