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Jason Veneman, David R. Novotny, Chriss A. Grosvenor, Robert T. Johnk, Seturnino Canales
We present and analyze a procedure for performing relative, ultra-wideband antenna pattern measurements in a non-ideal EM facility. Ultra-wideband, short-impulse, TEM horn transmission measurements were performed and compared with computer-modeled
Chriss A. Grosvenor, David R. Novotny, Jason Veneman, Seturnino Canales
TEM, time-domain antennas are designed to reproduce accurately the time characteristics of an impulsive, incoming field. The response to the fields must be constant in amplitude and linear in phase for minimal distortion. Numerical techniques are employed
We present results for uncertainties in noise-parameter measurements, obtained using a Monte Carlo simulation of the measurements. Sets of data were generated to simulate measurements on a low-noise amplifier, with given uncertainties in the underlying
This paper reports the formulation and results of a Monte Carlo study of uncertainties in noise-parameter measurements. The simulator permits the computation of the dependence of the uncertainty in the noise parameters on uncertainties in the underlying
We describe the apparatus, software, and measurement procedures for a pulsed inductive microwave magnetometer (PIMM). PIMM can measure the dynamical properties of materials used in recording heads for magnetic storage applications and it can be used as a
Marco Candidi, Christopher L. Holloway, Perry F. Wilson, Dennis G. Camell
In this paper we present a comparison of radiated emission measurements from four test facilities (reverberation chamber, GTEM cell, OATS, and fully anechoic chamber)for two different devices. The use of a dipole model to correlate emission data between
John M. Martinis, Sae Woo Nam, Joe Aumentado, C Urbina
We have designed and operated a circuit based on a large-area current-biased Josephson junction whose two lower energy quantum levels could be used to implement a solid-state qubit. The circuit allows measurement of the qubit states with a fidelity of 85%
Christopher L. Holloway, R. Garzia, John M. Ladbury, David A. Hill, Galen H. Koepke
The use of advanced composite material (ACM) is drawing considerable attention in recent years as an alternative to metals. In many applications, these materials must have the ability to shield electromagnetic fields. Shielding effectiveness (SE) is the
Eyal Gerecht, V. A. Bhupathiraju, Erich N. Grossman, Jeffrey W. Nicholson, Fernando Rodriguez-Morales, Dazhen Gu, Sigfrid Yngvesson
We have developed a process for fabricating a thin NbN film at the National Institute of Standards and Technology in Boulder, CO. A two-fold approach can be taken. The first is to maximize the critical temperature of the superconducting device (growing
Eyal Gerecht, Carl D. Reintsema, Erich N. Grossman, A. L. Betz, R. T. Boreiko
We are reporting a noise temperature measured on a diffusion-cooled hot electron bolometeric (DHEB) mixer designed for a heterodyne focal plane array to study lines with frequencies of 2 THz and above. Our fabrication process utilizes selective ion milling
Chriss A. Grosvenor, David R. Novotny, Robert T. Johnk, Seturnino Canales, Jason Veneman
In this paper we discuss the direct illumination and reverberation chamber techniques for measuring shielding effectiveness. using the reverberation chamber as our reference, we explain the differences between the measurements and corrections applied to
This paper discusses the effects that finite conductors have on the propagation characteristics of planar transmission lines structures. Closed form expressions for the attenuation constant and the resistance per unit length for various planar structures
Perry F. Wilson, Marco Candidi, Christopher L. Holloway
The emission patterns from electrically large objects are complex and require time consuming spherical scans to determine the emissions maximum. A planar cut from the spherical pattern is a relatively easy measurement to make and resembles the techniques
We show that the coupling between a sensor in an electrically large cavity and the outside world is a very complicated problem, with small changes inside the cavity resulting in signal changes of greater than 20 dB. However, this problem can be greatly
Donna Beals, Christopher L. Holloway, Paul McKenna
In this paper we discuss the use of a field mapping approach for determining chamber quality. Both measurements and simulation results are used to illustrate this approach.
A pseudo-isotropic source is presented. The source consists of an electrically-large cavity with internal excitation (horn antenna), a variable internal boundary condition (a rotating paddle as in a reverberation chamber), and randomly placed apertures for
Claude Weil, Dennis G. Camell, David R. Novotny, Robert T. Johnk, Arthur Ondrejka
We discuss simulator units for calibrating across-the-road Doppler traffic radars used in highway speed enforcement. Two units of essentially the same design were developed, one operating at K-Band (24 GHz) and the other at Ka-Band (35 GHz). The signal
Michael D. Janezic, Edward Kuester, James R. Baker-Jarvis
In this paper we present a new theoretical model, based on the mode-matching method, for making nondestructive permittivity and loss tangent measurements using the split-cylinder resonator. This new model properly takes into account the fringing electric
James R. Baker-Jarvis, Raian K. Kaiser, Michael D. Janezic
The purpose of this paper is to discuss the characterization of materials that mimic the electromagnetic characteristics of the human body from low frequencies to 10 MHz and over a temperature range of 15 C. to 40 C. The materials studied were: 1) a
It is difficult to characterize many antenna systems in a laboratory environment. Size is the major consideration, but an increasing number of sophisticated antennas are being placed at remote sites where they are simply inaccessible. Of particular concern
Erich N. Grossman, V. A. Bhupathiraju, Aaron J. Miller, Carl D. Reintsema
We describe the status of, and present the first imagery obtained using, an active uncooled mm-wave microbolometer-based imaging system. The microbolometers consist of 2 mm x 6 mm x .02 mm Nb films, coupled to the incident field by annular slot antennas
Richard G. Geyer, Melanie W. Cole, P. C. Joshi, E. Ngo, C. Hubbard, W. Nothwang, M. Bratcher, M. Ervin, M. Wood
The influence of low concentration (1 mol%) Mg doping on the structural, microstructural, surface morphological and dielectric properties of Ba 1-xSr xTiOd3^ thin films has been measured and analyzed. The films were fabricated on MgO and Pt-Si substrates
James R. Baker-Jarvis, Raian K. Kaiser, Michael D. Janezic, Nicholas Paulter, Ken L. Stricklett
The purpose of the work described in this report is to develop and characterize materials that mimic the electromagnetic characteristics of the human body. The materials will be used to simulate the relevant electromagnetic properties of the human body
Melanie W. Cole, P. C. Joshi, E. Ngo, C. Hubbard, M. Ervin, M. Wood, Richard G. Geyer
The influence of low concentration (1 mol%) Mg-doping on the structural, microstructural, surface morphological and dielectric properties of Ba (1-x)Srd(x)TiO (3) thin films has been measured and analyzed. The films were fabricated on MgO and Pt-Si
Erich N. Grossman, Todd E. Harvey, Carl D. Reintsema
The nonlinear electrical transport properties of metal-insulator-metal (MIM) tunnel diodes based on a barrier of naturally grown niobium oxide have been measured at room temperature and analyzed. In most cases excellent agreement is found between the