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Christopher Eio, David Adamson, James P. Randa, Djamel Allal, Rinadij Uzdin
A measurement comparison of noise temperature has been carried out between four National Metrology laboratories in coaxial line at 30 MHz, 60 MHz and 1 Ghz. The identification of this intercomparison is CCEM.RF-K18.CL. Two noise sources have been measured
Kate Remley, Paul D. Hale, David I. Bergman, Darryl A. Keenan
We compare measurements of simple multisines using instruments capable of characterizing both magnitude and relative phase the measured signals. All three instruments we compared reported relative phase measurements within a few degrees of each other at
Ying-Ju Wang, Matthew Eardley, Svenja A. Knappe, John M. Moreland, Leo W. Hollberg, John Kitching
We demonstrate a direct resonant interaction between the mechanical motion of a mesoscopic resonator and the spin degrees of freedom of a sample of neutral atoms in the gas phase. This couplin, mediated by a magnetic particle attached to the tip of the
Dylan Williams, Tracy S. Clement, Paul D. Hale, Andrew Dienstfrey
We discuss procedures for calibrating high-speed sampling oscilloscopes at the National Institute of Standards and Technology, and the terminology associated with those calibrations. The discussion clarifies not only the calibration procedures, but how to
Lorentz microscopy was used to study the micromagnetic structure and magnetization reversal in magnetic tunnel junctions (MTJs) fabricated with different processing conditions including a preoxidation process. The authors find that the free layer in a MTJ
Pavel Voskoboynik, Ronald D. Joos, W E. Doherty, Ronald B. Goldfarb
Positive-intrinsic-negative (PIN) silicon diodes are commonly used in magnetic resonance imaging (MRI) coils to perform active or passive blocking and detuning, or to disable circuit functions. However, diode packages with large magnetic moments are known
In a publication we derived and presented two closed-form expressions for the current distribution on the ground plane of a microstrip line. One expression was based on the assumption of a constant current distribution on the trace conductor. The second
We introduce a novel transmission line method for measurements of the penetration depth of thin high temperature supervonducting (HTS) films. The method is based on the accurate extraction of the inductance-per-unit-length of a superconducting coplanar
Christopher L. Holloway, David A. Hill, John M. Ladbury, Perry F. Wilson, Galen H. Koepke, Jason Coder
With the proliferation of wireless devices in recent years, there is a growing need to test the operation and functionality of these various devices in different multipath radio propagation environments, ranging from a direct line-of-sight environment to a
M. Myslinski, Kate Remley, Dominique Schreurs, Bart Nauwelaers
This paper presents a simple test-bench providing RF vector measurements of typical wireless communication system building blocks under realistic signal conditions. The instruments are synchronized using an experimental method based on the signal path's
Eyal Gerecht, Dazhen Gu, Fernando Rodriquez-Morales, Sigfrid Yngvesson
Imaging and spectroscopy at terahertz frequencies (defined roughly as 300 GHz-3 THz) have great potential for both healthcare and homeland security applications. Terahertz frequencies correspond to energy level transitions of important molecules ibbiology
Massimo Pasquale, Sergio Perero, Giorgio Bertotti, Pavel Kabos
We have analyzed the microwave behavior of soft nanogranular (Fe 0.7uCo 0.3u) 71uB 22uNi films with thickness of 136, 195 and 236 nm which present a dc relative permeability from 60 to 280, a resistivity of 8 to 9×10 7d Ω}m and a zero-field double
We use a rotating dihedral to determine the cross-polarization ratios of radar cross section measurement systems. Even a small amplitude drift can severely degrade the calibration accuracy, since the calibration relies on accurate determination of
This textbook is written for the experimentalist starting in the laboratory -- beginning graduate students, industry measurement engineers, and materials scientists interested in learning how to design successful low-temperature (1 K to 300 K) measurement
L. Yuan, Lan Gao, R. Sabirianov, Sy-hwang Liou, Michelle Chabot, Dong-Hoon Min, John M. Moreland, Bao Shan Han
Microcantilever torque magnetometry (MTM) is a sensitive tool to measure small magnetization changes in the sample. In this paper, we investigated a process for preparing patterned magnetic films on cantilevers and studied the magnetic interactions of a
James R. Baker-Jarvis, Michael D. Janezic, Derik Love, Thomas Mitchell (Mitch) Wallis, Christopher L. Holloway, Pavel Kabos
In this paper we present a simple experimental procedure for studying the phase velocity behavior of a metafilm with tunable material properties. Using this approach we have studied the phase-velocity behavior of a metamaterial under different conditions
Christopher L. Holloway, Galen H. Koepke, Dennis G. Camell, Catherine A. Remley, Susan A. Schima, M. McKinley, Robert T. Johnk
In this report, we investigate radio communications problems faced by emergency responders (firefighters and police) in disaster situations such as collapsed buildings. A fundamental challenge to communications into and out of large buildings is the strong
Jeffrey R. Guerrieri, Michael H. Francis, Perry F. Wilson, Leonard E. Miller, Nelson Bryner, David Stroup, Luke Klien-Berndt
An indoor localization and communication project is described that proposes to use RFID (radio-frequency identification) tags, placed in the building beforehand, as navigation waypoints for an inertial navigation system carried by a first responder. RFID
Katherine MacReynolds, Jeffrey R. Guerrieri, Michael H. Francis, Douglas T. Tamura
This paper describes the new tabletop millimeter wave extrapolation range which will provide on-axis gain services up to 110GHz. A discussion of the extrapolation measurement method [1], as presented at the Antenna Measurements Techniques Association (AMTA
Thomas Mitchell (Mitch) Wallis, John M. Moreland, Pavel Kabos
A new methods is presented for determining the magetomechanical ratio, g', in a thin ferromagnetic film deposited on a microcantilever via measurement of the Einstein-de Haas effect. An alternating magnetic field applied in the plane of the cantilever and
Christopher L. Holloway, Galen H. Koepke, Dennis G. Camell, Kate Remley, S. A. Schima, Dylan Williams
For various applications, there is a growing need to understand the shielding and/or attenuation properties of large buildings and structures. In this paper, we present experimental data for the coupling of electromagnetic fields into various types of
We review the advantages of a national standard for microwave brightness temperature and outline our proposed approach toward developing such a standard. The proposal is a combined standard that would comprise both a standard radiometer, traceable to
Kate Remley, M. Myslinski, Dominique Schreurs, Bart Nauwelaers
This work presents for the first time wideband Large Signal Network Analyzer (LSNA) measurements used to extract a large-signal behavioral model of an RF amplifier. The methodology together with some important issues concerning the data processing is
Matthew Pufall, Billy F. Riddle, Stephen E. Russek, John Kakareka, Jordan A. Katine
We have investigated the interaction mechanism between two nanocontact spin transfer oscillators made on the same magnetic spin valve multilayer. The oscillators phase lock when their precession frequencies are made similar, and a giant magnetoresistance