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The finite-difference time-domain (FDTD) method is used to investigate whether the currents induced on equipment under test (EUT) in a transverse electromagnetic (TEM) cell are similar to those induced in a free-space environment. The approach is to
This paper introduces readers to two informal meetings where microwave engineers can learn techniques, share experiences, and discuss the latest research in nonlinear and large-signal measurements. The Automatic RF Techniques Group ,ARFTG, Nonlinear
Many modern high-speed oscilloscopes are well suited for precise microwave waveform, modulated-signal, and nonlinear measurements. These oscilloscopes have bandwidths of up to 100 GHz and are available with nominally 50 ? input impedances. Like their low
Christopher L. Holloway, John M. Ladbury, Jason Coder, Galen H. Koepke, David A. Hill
For various applications, there is a growing need to determine the shielding effectiveness of physically small, but electrically large, enclosures or cavities. In this paper, we present a reverberation chamber technique for measuring the SE of such
James R. Baker-Jarvis, Michael D. Janezic, John H. Lehman
We describe a dielectric resonator-based measurement method for determining the electrical conductivity of carbon nanotubes and nanowires at microwave to millimeter frequencies. This measurement method is not limited by the contract resistance or impedance
Robert T. Johnk, Robert Scully, David R. Novotny, Chriss A. Grosvenor, Nino Canales, Dennis G. Camell, Galen H. Koepke
This paper summarizes a joint NIST-NASA measurement effort to evaluate the electromagnetic penetration of the shuttle Endeavour. NASA is concerned about the effects that microwave imaging radar systems might have on critical avionics systems on its fleet
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
Jason B. Coder, John M. Ladbury, Christopher L. Holloway
We examine the current method for determining the shielding effectiveness of a material using nested reverberation chambers and show a simplified approach. Included in our examination is a discussion of the purpose for using a four antenna measurement
Dennis G. Camell, Michael Taylor, Robert T. Johnk, Benjamin Davis
This paper summarizes a joint NIST Industry measurement effort. Time domain and field uniformity measurements are used to verify a retro-fit of RF absorber in an EMC Compliance Chamber from 30 MHz to 6 GHz. Time gating and dense frequency packing of
Ever since William Gilbert's 16th century treatise "De Magnete," it has been known that magnetic fields can be used to manipulate the magnetic orientation of ferromagnets. This has been the foundation for electronic applications of magnetic materials for
Kate Remley, Jeffrey R. Guerrieri, Dylan Williams, David R. Novotny, Anthony B. Kos, Nelson Bryner, Nader Moayeri, Michael Souryal, Kang Lee, Steven Fick
This article reports on activities being carried out by the National Institute of Standards and Technology to ensure secure, reliable use of Radio-Frequency Identification (RFID) technology in homeland security and public safety applications. These
We report on a technique for extracting an accurate value of the nonlinear inductance DL(i) in superconducting transmission lines. The novelty of this technique is to assess the frequency dependence of the transmission line nonlinear response. A wideband
Daniel C. van der Laan, John (Jack) W. Ekin, Cameron C. Clickner, Theodore C. Stauffer
We present a new experimental technique to measure the delamination strength under transverse tensile stress of YBa 2Cu 3O 7-δ coated conductors for electric power applications. The delamination strength, defined as the tensile stress at which the ceramic
Atif A. Imtiaz, Thomas Baldwin, Hans T. Nembach, Thomas M. Wallis, Pavel Kabos
We measured bulk dielectric (Fused Silica), semiconductor (Silicon) and metal (Copper), with a Near-field Scanning Microwave Microscope (NSMM). We use three bulk materials to test the existing quasi-static theoretical approach to de-embed the materials
Catherine A. Remley, Joe Gering, Susan L. Sweeney, C. Michael Olsen, Cliff Xie, Dave K. Walker, Tom McKay, John J. Pekarik
We describe an interlaboratory measurement comparison of distortion in a CMOS low-noise device operating under weakly nonlinear conditions. Issues that commonly arise in performing and interpreting nonlinear measurements are discussed, such as power vs
Nathan D. Orloff, Jordi Mateu, Makoto Murakami, Ichiro Takeuchi, James C. Booth
We develop a measurement technique for obtaining the broadband complex permittivity of thin-film dielectric materials over the frequency range from 100 Hz-40 GHz. Such broad frequency coverage can only be accomplishe3d by combining lumped-element and
Jordi Mateu, Nate Orloff, Matthew Rinehart, James Booth
We present a semi-analytical procedure to extract the permittivity of fluids from measurements in our microfluidic-microelectronic platform. This platform consists of broadband coplanar waveguide transmission lines with embedded microfluidic channels on
Jeffrey Jargon, Jolene Splett, Dominic F. Vecchia, Donald C. DeGroot
We develop an empirical model for the warm-up drift in a harmonic phase standard used to calibrate the phase distortion of a nonlinear vector network analyzer. The model enables us to estimate the time at which the standard reaches stability.
Najib Cheggour, John (Jack) W. Ekin, Loren F. Goodrich
The dependence of transport critical-current (I c on axial tensile strain ε was measured for a developmental Nb 3Sn multifilamentary strand as a function of magnetic field B between 12 T and 16 T, at the temperature of 4 K. This conductor was from the
We studied the systematic effect of current ripple on the determination of n-value, which is the index of the shape of the electric field-current (E-I) curve. Commercial Nb 3Sn wires were measured with controlled amounts of ac ripple. Substitution-box
We present harmonic generation measurements of the intrinsic nonlinear current density j2 of (YBCO) films at temperatures close the Tc. Experiments on a range of different quality samples allow us to extract the dependence of j2 on the penetration depth of
Najib Cheggour, John (Jack) W. Ekin, C. L. H. Thieme, Y Y. Xie
The slitting of wide Y-Ba-Cu-O coated-conductor tapes to a width desirable for applications allows a considerable reduction in conductor manufacturing cost. Localized damage induced at the slit edges may be tolerated provided that mechanical cracks formed
Superconductor thin films are known to possess a nonlinear response at microwave frequencies. These nonlinear effects can be described quantitatively by a nonlinear inductance, and for high-Tc superconductors, are believed to be an intrinsic consequence of
James R. Baker-Jarvis, Billy F. Riddle, Michael D. Janezic
In this paper we develop a model that can describe broadband dielectric response, and includes frequency-dependent loss and the effects of the local electric field. The model is based on a correlation-function approach that we previously developed using
Thomas Gerrits, Pavol Krivosik, Michael Schneider, C E. Patton, Thomas J. Silva
The longitudinal magneto-optical Kerr effect is used to obtain a calibrated measure of the dynamic magnetization response over the ferromagnetic resonance (FMR) profile for in-plane magnetized Permalloy films excited with high power in-plane transverse