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Parrish Ralston, Tam H. Duong, Nanying Yang, David W. Berning, Colleen E. Hood, Allen R. Hefner Jr., Kathleen Meehan
Adequate modeling of a power MOSFET is dependent on accurate characterization of the inter-electrode capacitances. With the advent of high voltage silicon carbide (SiC) power MOSFETs, it has become important to develop a measurement system that can perform
Catherine A. Remley, Christopher L. Holloway, David W. Matolak
This document reports on wireless channel measurements and models for outdoor to indoor propagation environments. Although there have been a number of publications that have recently appeared on this topic, e.g., [1], [2], and references therein, the
We demonstrate a new technique to monitor the polarization-mode dispersion in a fiber communication channel by analyzing the modulated data at the fiber output measured with Polarization-Sensitive Linear Optical Sampling (PS-LOS).
Ravikiran Attota, Richard M. Silver, Thomas A. Germer
We present a novel optical technique that produces nanometer dimensional measurement sensitivity using a conventional optical microscope, by analyzing through-focus scanning-optical-microscope (TSOM) images obtained at different focus positions. In
Nadine E. Gergel-Hackett, Behrang H. Hamadani, B Dunlap, John S. Suehle, Curt A. Richter, Christina A. Hacker, David J. Gundlach
We have fabricated physically flexible nonvolatile memory devices using inexpensive, room-temperature, solution processing. The behavior of these devices is consistent with that of a memristor device, the missing fourth circuit element theoretically
The uncertainty analysis is presented for NIST measurements of noise parameters of amplifiers and transistors, in both connectorized (coaxial) and on-wafer environments. We treat both the X-parameters, which are based on the wave representation of the
Tasshi Dennis, Paul A. Williams, Ian R. Coddington, Nathan R. Newbury
We demonstrate word-synchronous measurements of QPSK format 40 Gb/s PRBS signals using linear optical sampling with a precision time-base, which allows us to average waveforms and distinguish between signal distortion and noise in eye diagrams.
Christopher L. Holloway, John M. Ladbury, Richard Ziolkowski, Peng Jin, Chia-Ching Lin
The paper discusses the analysis and measurements of electrical small antennas. The antennas discussed here are based on antenna designed from metamaterial inspired concepts. An electromagnetic reverberation chamber is used for the test of the antennas. A
Jeffrey A. Jargon, Xiaoxia Wu, Laurie Christian, Bo Zhang, Wei-Ren Peng, Jeng-Yuan Yang, Lin Zhang, Scott Nuccio, Loukas Paraschis, Alan Willner
We experimentally demonstrate a technique for monitoring the time misalignment of in-phase/quadrature (I/Q) data streams and pulse carver/data in a 20-Gb/s return-to-zero differential quadrature phase-shift-keying (RZ-DQPSK) transmitter. By measuring the
Comparison calibrations of microphones based on the reciprocity method are performed with both the microphone under test and a reference standard microphone inserted into an acoustical coupler. For these calibrations, the wave motion correction W is needed
Direct-sequence spread-spectrum underwater acoustic communications are analyzed in this paper between communication nodes, at least one of which is moving. At-sea data are analyzed which show that the phase change due to source motion is significant. The
We present a new method for analyzing eye diagrams that always provides a unique solution by making use of a robust, least-median-of-squares (LMS) location estimator. In contrast to commonly used histogram techniques, the LMS procedure is insensitive to
Catherine A. Remley, Nuno Carvalho, Dominique Schreurs, Kevin Gard
We discuss the use of multisine test signals for system verification and model development in the laboratory. We highlight the utility of multisine excitation for test and verification of telecommunication systems, where nonlinear elements such as power
A brief summary is presented for the uncertainty analysis for measurements of noise parameters of amplifiers and transistors, in both connectorized (coaxial) and on-wafer environments. We treat both the X-parameters, which are based on the wave
Catherine A. Remley, Galen H. Koepke, Christopher L. Holloway, Chriss A. Grosvenor, Dennis G. Camell, John M. Ladbury, Robert Johnk, David R. Novotny, William F. Young, George Hough, Michael McKinley, Yann Becquet, John Korsnes
We report on measurements of parameters utilized for characterization of broadband wireless technologies proposed for use by emergency responders (firefighters, police, and emergency medical personnel) and other public-safety personnel. We designed a
Jon E. Bjarnason, Charles Dietlein, Erich N. Grossman
In gas spectroscopy, chemicals can be identified by the set of frequencies at which their absorption lines occur. The concentration can be quantitatively estimated from the intensity of any of the absorption lines. The sensitivity of the spectrometer, i.e
Charles Dietlein, Jon E. Bjarnason, Erich N. Grossman, Zoya Popovic
Conventional material measurements of transmission and reflection in the millimeter-wave and terahertz frequency range do not differentiate between scattering and absorption, grouping effects from both mechanisms together into 'loss'. Accurate knowledge of
Nathan A. Tomlin, James A. Beall, Gene C. Hilton, Kent D. Irwin, Galen O'Neil, Dan Schmidt, Leila R. Vale, Joel Ullom
We demonstrate successful cooling of an X-ray transition-edge sensor (TES) using solid-state refrigerators based on normal-metal/insulator/superconductor (NIS) tunnel junctions. Above the TES transition temperature (Tc), we use Johnson noise thermometry to
David T. Read, Walter Gerstle, Stewart Silling, Vinod K. Tewary, Richard Lehoucq
A theoretical framework, based upon the peridynamic model, is presented for analytical and computational simulation of electromigration. The framework allows four coupled physical processes to be modeled simultaneously: mechanical deformation, heat
Leonardo Hillkirk, Allen R. Hefner Jr., Robert W. Dutton
This paper presents a selection of results from numerical studies addressing various problems highly relevant to the operation of SiC power devices in power systems such as the speed optimization of high-voltage SiC PiN diodes and the operation of SiC
Using finite element analysis, we calculate the temperature range and the resulting cyclic Von Mises strain resulting from Joule heating, generated by the application of alternating current, applied to specimens representative of commercial copper
We discuss the sources of uncertainty in near-field measurements and their impact on far-field antenna parameters. The methods of estimating these uncertainties can be considered in three broad categories: theoretical estimation (analytical), computer
Dennis G. Camell, Robert Johnk, David R. Novotny, Chriss A. Grosvenor
This paper demonstrates the usefulness of time-domain processing to determine free-space antenna factors (FSAF) for electromagnetic compatibility (EMC) antennas. Our procedures are explained and data are provided for frequencies from 30 MHz to 9GHz. We
Robert Keller, Nicholas Barbosa, Roy H. Geiss, David T. Read
A novel approach for measuring thermal fatigue lifetime and ultimate strength of patterned thin films on substrates is presented. The method is based on controlled application of cyclic joule heating by means of low-frequency, high-density alternating
In this article, we describe two engineer-friendly events - the Automatic RF Techniques Group (ARFTG) Nonlinear Measurements Workshop and the Nonlinear Vector Network Analyzer (NVNA) Users' Forum - designed to let participants learn about and discuss