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NIST Authors in Bold

Displaying 401 - 425 of 774

Nanoscale Measurements with a Through-Focus Scanning-Optical-Microscope

July 15, 2009
Author(s)
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

Flexible Solution-Processed Memristors

June 3, 2009
Author(s)
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

Uncertainty Analysis for Noise-Parameter Measurements at NIST

April 9, 2009
Author(s)
James P. Randa
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

Word-synchronous linear optical sampling of 40 Gb/s QPSK signals

March 20, 2009
Author(s)
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.

Measurements of Metamaterial-Inspired, Electrically Small Antenna Systems

March 2, 2009
Author(s)
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

Synchronization monitoring of I/Q data and pulse carving misalignment for a parallel-type 20-Gb/s RZ-DQPSK transmitter by measuring RF clock tone/low frequency power

December 15, 2008
Author(s)
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

A robust algorithm for eye-diagram analysis

November 1, 2008
Author(s)
Jeffrey A. Jargon, Paul D. Hale, Chih-Ming Wang
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

Multisine Signals for Wireless System Test and Design

June 13, 2008
Author(s)
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

Uncertainty Analysis for Noise-Parameter Measurements

June 8, 2008
Author(s)
James P. Randa
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

Measurements to Support Modulated-Signal Radio Transmissions for the Public-Safety Sector

April 1, 2008
Author(s)
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

Operation of an X-ray transition-edge sensor cooled by tunnel junction refrigerators

January 19, 2008
Author(s)
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

Peridynamic Simulation of Electromigration

January 1, 2008
Author(s)
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

Sources of Uncertainty for Near-Field Measurements

November 11, 2007
Author(s)
Michael H. Francis, Ronald C. Wittmann
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

Free Space Antenna Factors through the Use of Time-Domain Signal Processing

September 1, 2007
Author(s)
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

Key nonlinear measurement events

August 1, 2007
Author(s)
Catherine A. Remley, Dominique Schreurs
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

Free Space Antenna Factors through the use of Time-Domain Signal Processing

July 8, 2007
Author(s)
Dennis G. Camell, Robert T. Johnk, David R. Novotny, Chriss A. Grosvenor
This paper demonstrates the usefulness of time domain processing to determine free-space antenna factors,FSAF, for EMC antennas. Procedures are explained and data is provided from 30 MHz to 9 GHz. We investigate time gating of dense frequency packed
Displaying 401 - 425 of 774
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