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1993 documents found for International Journal
Coupled ring resonator for microwave characterization of dielectric materials
Mahima Kapoor, K. S. Daya, G. S. Tyagi
Published online : 01-04-2012
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In this paper characterization of dielectric materials in liquid and powder phase using concentric closed and split ring resonators of length ?, ?/, and ?/ is reported. Experimental results have been validated by simulations and theoretically modeling. Sensitivity of the resonator with closed rings was maximum. Experimentally extracted values of dielectric constant of ferrite ranged from 14.05 to
IJMWT Special Issue on the 2011 National Microwave Days in France
Alain Peden, Jean-François Favennec
Published online : 01-01-2012
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Comparative study of RF MEMS micro-contact materials
Adrien Broué, Jérémie Dhennin, Pierre-Louis Charvet, Patrick Pons, Nourredine Ben Jemaa, Peter Heeb, Fabio Coccetti, Robert Plana
Published online : 01-08-2012
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A systematic comparison between several pairs of contact materials based on an innovative methodology early developed at NOVA MEMS is hereby presented. The technique exploits a commercial nanoindenter coupled with electrical measurements, and test vehicles specially designed to investigate the underlying physics driving the surface-related failure modes. The study provides a comprehensive understa
Directional propagation channel estimation and analysis in urban environment with panoramic photography
Jean-Marc Conrat, Patrice Pajusco
Published online : 01-02-2012
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This article aims to provide readers with a physical understanding of the propagation channel that is complementary to mathematical channel modeling. It presents an analysis of the directional propagation channel based on radiophotos. Radiophotos are graphical objects where directions of arrival are superimposed on three-dimensional (3D) panoramic photographs. The interaction between electro magne
A new technique for SBAS availability improvement
Boriana Vassileva, Boris Vassilev
Published online : 01-04-2012
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To protect a worst-case user, Satellite-Based Augmentation System (SBAS) transmits inflated integrity information for protection level computation. In this work, a novel user-based technique for autonomous protection level computation is proposed. Its quality is examined over Key Performance Indicators tests for integrity and availability using real European Geostationary Navigation Overlay Servic
Slot coupled patch antenna in MCM-D for millimeter wave detector matrix applications
Vahid Tavakol, Feng Qi, Ilja Ocket, Dominique Schreurs, Walter De Raedt, Bart Nauwelaers
Published online : 01-08-2012
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In this work we assess the feasibility of fabricating a matrix of antennas for the millimeter (mm)-wave band using the ?Multi Chip Module ? Deposited (MCM-D)? process. The main focus of the design is to minimize the cross coupling between the antennas fabricated on the common substrate. We investigate the use of a virtual cavity formed by metalized vias in order to reduce the cross coupling to the
Optimization of a 61.44 GHz BiCMOS HBT integrated PLL for ultra-fast settling time
Atheer Barghouthi, Marcu Hellfeld, Corrado Carta, Frank Ellinger
Published online : 01-08-2012
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The design of a 61.44 GHz integrated Phase-locked loop (PLL) on a 180 GHz BiCMOS technology is presented. The PLL was optimized for a very fast settling time of 4 µs as required by the system specifications. Because the receiver is using a carrier recovery circuit that can follow the slow changes of the carrier such as phase noise, the sensitivity of the bit error rate to phase noise at the receiv
On the oscillation limits of HBT cross-coupled oscillators
Atheer Barghouthi, Corrado Carta, Udo Jörges, Frank Ellinger
Published online : 01-08-2012
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In evaluating the potential of a given integrated-circuit technology, the negative conductance approach is used to estimate a maximum frequency limit for the ability of Heterojunction Bipolar Transistor (HBT) cross-coupled architecture to function as an oscillator at high frequencies. In this paper, the simple low-frequency estimation of the negative conductance, commonly used in the literature, i
A 77-GHz antenna and fully integrated radar transceiver in package
A. Fischer, A. Stelzer, L. Maurer
Published online : 01-08-2012
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A 77-GHz?directional folded dipole antenna integrated in an embedded wafer level ball grid array package is presented. For the characterization of the antenna, a frequency multiplier is embedded, which scales the 4.25-GHz input signal up to 76.5 GHz and allows the use of a commercial signal source. The antenna structure is manufactured at the metallic layer, in the fan-out area of the package, and
RF MEMS ohmic switches for matrix configurations
Giorgio De Angelis, Andrea Lucibello, Emanuela Proietti, Romolo Marcelli, Giancarlo Bartolucci, Federico Casini, Paola Farinelli, Giovanni Mannocchi, Sergio Di Nardo, Daniele Pochesci, Benno Margesin, Flavio Giacomozzi, Olivier Vendier, Taeyoung Kim, Larissa Vietzorreck
Published online : 01-08-2012
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Two different topologies of radio frequency micro-electro-mechanical system (RF MEMS) series ohmic switches (cantilever and clamped?clamped beams) in coplanar waveguide (CPW) configuration have been characterized by means of DC, environmental, and RF measurements. In particular, on-wafer checks have been followed by RF test after vibration, thermal shocks, and temperature cycles. The devices have
MRF volume 4 issue 1 Cover and Back matter
Published online : 01-02-2012
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MRF volume 4 issue 1 Cover and Front matter
Published online : 01-02-2012
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High-range resolution multichannel DVB-T passive radar: aerial target detection
Dario Petri, Amerigo Capria, Michele Conti, Fabrizio Berizzi, Marco Martorella, Enzo Dalle Mese
Published online : 01-04-2012
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A method for improving range resolution in passive radar system is to jointly use more than one transmission channel of the same illuminator of opportunity (IO). This paper specifically focuses on the exploitation of multiple adjacent digital video broadcasting-terrestrial (DVB-T) channels for achieving high-range resolution profiles with a passive radar system operating in air surveillance scenar
Verification of ADS-B positioning by direction of arrival estimation
Christoph Reck, Max S. Reuther, Alexander Jasch, Lorenz-Peter Schmidt
Published online : 01-04-2012
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ADS-B provides convenient means of air traffic control (ATC) for its low cost and simple ground station hardware. In a low percentage of cases, aircraft positions transmitted via ADS-B are error prone due to e.g. faulty wiring with onboard navigation systems. In the proposed approach, direction of arrival (DOA) estimation is used to verify ADS-B airborne positions. The potential positioning error
Efficient location strategy for airport surveillance using Mode-S multilateration systems
Ivan A. Mantilla-Gaviria, Mauro Leonardi, Gaspare Galati, Juan V. Balbastre-Tejedor, Elías de Los Reyes Davó
Published online : 01-04-2012
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In this paper, the use of regularization methods to solve the location problem in multilateration systems, using Mode-S signals, is studied, evaluated, and developed. The Tikhonov method has been implemented as a first application to solve the classical system of hyperbolic equations in multilateration systems. Some simulations are obtained and the results are compared with those obtained by the w
A multimodal sensor system for runway debris detection
Helmut Essen, Wolfgang Koch, Sebastian Hantscher, Rüdiger Zimmermann, Paul Warok, Martin Schröder, Marek Schikora, Goert Luedtke
Published online : 01-05-2012
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For foreign object detection on runways, highly sensitive radar sensors give the opportunity to detect even very small objects, metallic and non-metallic, also under adverse weather conditions. As it is desirable for airport applications to install only small but robust installations along the traffic areas, millimeter-wave radars offer the advantage of small antenna apertures and miniaturized sys
Some OFDM waveforms for a fully polarimetric weather radar
Piet van Genderen, Oleg A. Krasnov, Zongbo Wang, Recep Firat Tigrek
Published online : 01-04-2012
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Retrieval of cloud parameters in weather radar benefits from polarimetric measurements. Most polarimetric radars measure the full backscatter matrix (BSM) using a few alternating polarized sounding signals. Using specially encoded orthogonal frequency division multiplexing (OFDM) signals however, the BSM can be measured in a single simultaneous transmission of two orthogonally polarized signals. B
Enhancing sensitivity for emitter geolocation
Göran Tengstrand, Peter Hultman, Jean-François Grandin, Dario Benvenuti, Börje Andersson, Anders Johansson
Published online : 01-04-2012
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Angle of arrival (AOA), time of arrival (TOA), and frequency of arrival (FOA) can be measured for a signal from multiple platforms. By combining such measurements it is possible to obtain high-accuracy emitter position estimates. This requires a data link with low latency and sufficient data-rate, and synchronization of the platforms in space, time, and search pattern. Typically several of the pla
Low-power 8-bit 5-GS/s digital-to-analog converter for multi-gigabit wireless transceivers
Behnam Sedighi, Mahdi Khafaji, Johann Christoph Scheytt
Published online : 01-06-2012
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We present a method to realize a low-power and high-speed digital-to-analog converter (DAC) for system-on-chip applications. The new method is a combination of binary-weighted current cells and R-2R ladder and is specially suited for modern BiCMOS technologies. A prototype 5 GS/s DAC is implemented in 0.13 ?m SiGe BiCMOS technology. The DAC dissipates 26 mW and provides an SFDR higher than 48 dB f
Transient analysis of the EM field coupling to multi-conductor transmission lines using the NILT method
Adnen Rajhi, Said Ghnimi, Ali Gharssallah
Published online : 01-08-2012
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A simple and efficient numerical inversion Laplace transform (NILT) algorithm is implemented in MATLAB environment based on the quotient difference method to solve the problem of electromagnetic (EM) field coupling to lossy or lossless multi-conductor transmission lines (MTL) illuminated by an EM incident field. Two major points are treated in this work for the lossy MTL system excited by an incid
Active frequency-tripler MMICs for 300 GHz signal generation
Ulrich Johannes Lewark, Axel Tessmann, Hermann Massler, Sandrine Wagner, Arnulf Leuther, Ingmar Kallfass
Published online : 01-06-2012
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Two frequency-tripler monolithic microwave integrated circuits (MMICs) reaching sub-millimeter-wave output frequencies of 315 GHz are presented. The convenient integration of transistor?based field effect transistor (FET) frequency multipliers into multifunctional MMICs is shown by integration of a single?stage frequency-tripler with a buffer amplifier generating ?0.5 dBm of peak output power at 2
A G-band cryogenic MMIC heterodyne receiver module for astronomical applications
Patricia Voll, Lorene Samoska, Sarah Church, Judy M. Lau, Matthew Sieth, Todd Gaier, Pekka Kangaslahti, Mary Soria, Sami Tantawi, Dan Van Winkle
Published online : 01-06-2012
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We report cryogenic noise temperature and gain measurements of a prototype heterodyne receiver module designed to operate in the atmospheric window centered on 150 GHz. The module utilizes monolithic microwave integrated circuit (MMIC) InP high electron mobility transistor (HEMT) amplifiers, a second harmonic mixer, and bandpass filters. Swept local oscillator (LO) measurements show an average gai
A high-gain high-power amplifier MMIC for V-band applications using 100 nm AlGaN/GaN dual-gate HEMTs
Dirk Schwantuschke, Christian Haupt, Rudolf Kiefer, Peter Brückner, Matthias Seelmann-Eggebert, Axel Tessmann, Michael Mikulla, Ingmar Kallfass, Rüdiger Quay
Published online : 01-06-2012
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In this paper we present the design and realization of a high-power amplifier in grounded coplanar transmission line technology using AlGaN/GaN dual-gate High electron mobility transistors (HEMTs) with a gate-length of 100 nm to achieve a high gain per stage and high output power. A large-signal model was extracted for the dual-gate HEMT based on the state-space approach. For the fabricated dual-s
Wireless multi-gigabit data transmission using active MMIC components at 220 GHz
Jochen Antes, Daniel Lopez-Diaz, Axel Tessmann, Arnulf Leuther, Hermann Massler, Thomas Zwick, Oliver Ambacher, Ingmar Kallfass
Published online : 01-06-2012
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In this paper we present a wireless data link for multi-gigabit transmission in the mmW frequency range. The link is realized using waveguide modules based on fully integrated 50 nm metamorphic high electron mobility transistor (mHEMT) transmit and receive millimeter wave monolithic integrated circuits (MMICs) and provides transmission of data rates up to 12.5 Gbit/s modulated on a 220 GHz carrier
An effective procedure to design the layout of standard and enhanced mode-S multilateration systems for airport surveillance
Ivan A. Mantilla-Gaviria, Mauro Leonardi, Gaspare Galati, Juan V. Balbastre-Tejedor, Elías de los Reyes Davó
Published online : 01-04-2012
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In this paper, an effective procedure to emplace standard and enhanced mode-S multilateration stations for airport surveillance is studied and developed. This procedure is based on meta-heuristic optimization techniques, such as genetic algorithm (GA), and is intended to obtain useful parameters for an optimal system configuration that provides acceptable performance levels. Furthermore, the proce
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