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1. Introduction 2. Noise Temperature as a Measure of Noise Power 3. Available Noise Power from a Resistor 4. The Zero-Point Noise Term and the Minimum Noise of an Amplifier 5. Noise-Temperature Standards and Measurement of One-Port Noise Sources 6
Here we report on the testing and measurements of the ad hoc array concept in buildings. The overall concept is to use randomly located or placed wireless devices in a coordinated manner in order to increase the radio frequency signal at otherwise
Our editing team is key to the success of the Transactions. The Associate Editors who commit to a term of service are dedicated individual who work on a strictly voluntary basis to ensure the high quality of the manuscripts that are published. this is not
We have evaluated the correction factor of a WR-15 (50 to 75 GHz) rectangular waveguide calorimeter using four different techniques. The four methods are in agreement. Our initial uncertainty analysis indicates that the technique with the lowest
Dazhen Gu, Amanda Cox, Derek A. Houtz, Dave K. Walker, James P. Randa, Robert L. Billinger
We report the characterization of blackbody reflections as a part of the recent progress on the development of brightness standards for microwave remote sensing at National Institute of Standards and Technology (NIST).Three blackbody targets at variable
Jason Coder, John M. Ladbury, Christopher L. Holloway, Kate Remley
In this paper we explore how placing the same amount of absorber in different locations within a reverberation chamber can have different loading effects. This difference can have a significant impact on measurement reproducibility, both for measurements
Jason B. Coder, John M. Ladbury, Christopher L. Holloway, Catherine A. Remley
In this paper we explore how placing the same amount of RF absorber in different locations within a reverberation chamber can have different loading effects. This difference can have a significant impact on measurement reproducibility, both for
We present experimental measurements and analysis of RF interference between a passive RFID system and a generic frequency hopping communications system in the 902 928 MHz ISM radio band. Interference in both directions is considered, RFID to
Joshua A. Gordon, Christopher L. Holloway, Steven R. Jefferts, Thomas P. Heavner
We are presently investigating the feasibility of developing a technique that will allow direct traceable microwave electric field (E-field) measurements. The new approach is based on atomic rf-resonance spectroscopy, where an applied electrical field
Randy Direen, David R. Novotny, Katherine MacReynolds
A near-field planar scanner is used to construct images of a nearby scene illuminated with millimeter-wave frequencies. We present our initial work in active millimeter-wave imaging, and how it applies to the detection of concealed weapons.
Here we report on measurements of the ad hoc array concept in an enclosed atrium/lobby area of a high-rise building in Denver, Colorado. A typical ad hoc network is limited to coverage area achieved by the useable coverage of single nodes; however, we seek
This editorial column in the Newsletter describes a recent "EMC for the Smart Grid" workshop held at Connectivity Week 2010 in Santa Clara, CA. The text is based on a meeting report from the workshop supplemented with remarks by the Associate Editor for
James R. Baker-Jarvis, Sung Kim, Luke Leschallinger, Justin Johnson, Brad Givot
The purpose of this report is to summarize the characterization of a number of high-frequency solid, liquid, and semisolid tissue-equivalent materials, from 200 MHz to 20 GHz. Carbon black and liquid mixtures were studied, but were found to be unsuitable
Michaela Kuepferling, Claudio Serpico, Matthew Pufall, William Rippard, Thomas Mitchell (Mitch) Wallis, Atif A. Imtiaz, Pavel Kabos
The field dependence of vortex oscillations in a spin-transfer metallic nanocontact, subject to in-plane, spatially uniform, external fields, is studied by measuring the power spectral density of the voltage across the device. The measured spectra as a
James R. Baker-Jarvis, Michael D. Janezic, Billy F. Riddle, Kim Sung
In this project we study the behavior of the permittivity and loss tangent of a class of materials that exhibit relaxation. For relaxation response we show that the permittivity is a monotonically decreasing function of frequency. Also, for many low-liss
This paper describes a simulation program that was developed to compare the uncertainties that would be expected with different measurement strategies for the noise parameters of connectorized amplifiers and of amplifiers or transistors on wafers. Both
Polarimetric radar cross section systems are characterized by polarimetric system parameters $\epsilon_h$ and $\epsilon_v$. These parameters can be obtained with the use of rotating dihedrals. The full polarimetric dataset as a function of the angle of
Atif A. Imtiaz, Thomas M. Wallis, SangHyun S. Lim, Jonathan Chisum, Zoya Popovic, Pavel Kabos
The Scanning Microwave Probe (SMP) is emerging as an important broadband metrology tool for characterizing the materials and devices in the micron and sub-micron length scales in the frequency range of 10 MHz to 110 GHz. In this document we establish three
Electronic devices designed for purposes other than transmitting and receiving electromagnetic fields nonetheless act as unintentional antennas. Measurement methods are needed to characterize these antennas for electromagnetic compatibility tests; however
James R. Baker-Jarvis, Michael D. Janezic, Donald C. DeGroot
KNOWLEDGE of the response of materials to electromagnetic (EM) fields in the frequency range of radio frequency (RF) through terahertz (THz) is critical to numerous research projects and electronic product development activities. Electromagnetic waves in
A very high frequency (VHF) version of the electrically small, coax-fed, three-dimensional (3D) magnetic EZ antenna was designed and tested. The fabricated antenna was formed by integrating a capacitively-loaded loop (CLL) element with a coaxially-fed
Kichul Kim, Thomas M. Wallis, Paul Rice, Chin J. Chiang, Atif A. Imtiaz, Pavel Kabos, Dejan Filipovic
Conductivity and contact resistance of 100 nm and 250 nm diameter platinum (Pt) nanowires (NWs) are investigated computationally and experimentally. Finite element method based full-wave modeling and circuit simulations are used in conjunction with
A local excitation of ferromagnetic resonance (FMR) and its detection were performed by using an open-ended radio frequency (RF) probe. THe RF probe is composed of a coaxial cable transmitting broadband RF waves over 10 GHz and a sharp tip attached to its