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The Characteristics of Iris-Fed Millimeterwave Rectangular Microstrip Patch Antennas

Description: From introduction: The fabrication of various iris-fed millimeterwave rectangular microstrip patch antennas is described. A model is proposed to describe the iris-fed antenna. Irises ranging in size from 15 percent of the area of the patch to the fully open waveguide are used to couple energy into the antenna. Resonance of the antenna is observed to be insensitive to the size of the iris for irises up to 115 percent of the size of the patch. A study is also made of th? relationship of coupling … more
Date: October 1983
Creator: Greenlee, D. H.; Kanda, Motohisa & Chang, David C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical Time-Domain Reflectometer Performance and Calibration Studies

Description: from Introduction: The measurement accuracy of the optical time-domain reflectometer (OTDR) is restricted in some applications by a limited operational dynamic range and by a lack of standardized test procedures. In an effort to better understand these restrictions, we have measured the range of linearity of some avalanche photodiodes used as backscatter detectors. Also, the effect of input launch conditions is examined and a possible standardized OTDR test procedure is proposed. Using these su… more
Date: June 1983
Creator: Danielson, B. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reference Flat Pulse Generator

Description: Introduction: A reference step-like pulse generator is described which has been developed at NBS. This generator can be used for accurately characterizing the step response of various kinds of trap ient recording equipment (oscilloscopes, waveform recorders, transient digitizers, etc.). Basic design principles are given as well as complete circuit diagrams and descriptions. An analysis of the output stage of the generator is presented together with the circuit models for developing a time-domai… more
Date: October 1983
Creator: Andrews, J. R.; Bell, B. A. & Baldwin, E. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Introduction to STARPAC: the Standards Time Series and Regression Package

Description: From preface: STARPAC documentation is being published as a series of Technical Notes. This Note is the first in the series. It gives an overview of the STARPAC library, defines conventions used in the documentation, provides an example using STARPAC subroutines, and presents general background material. This Note includes information which is essential for using the STARPAC library, and users should be familiar with its contents before attempting to use any STARPAC subroutine.
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear Least Squares Regression Using STARPAC: The Standards Time Series and Regression Package

Description: From preface: This Note documents 16 subroutines for nonlinear least squares regression. Twelve of these compute the least squares estimates, performing either weighted or unweighted analysis with either numerically approximated or user-supplied (analytic) derivatives. The other four are user-callable subroutines for two procedures used within the estimation code: the first selects optimum step sizes for approximating the partial derivatives of the model; and the second checks the validity of a… more
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Equation of State for Fluid Ethylene

Description: Abstract: A thermodynamic property formulation for ethylene, developed as a part of a joint industry-government project, is presented. The formulation includes an equation of state, vapor pressure equation, and equation for the ideal gas heat capacity. The coefficients were determined by a least squares fit of selected experimental data. Comparisons of property values calculated using the equation of state with measured values are given. The equation of state is not valid in the critical region… more
Date: July 1981
Creator: McCarty, Robert D. & Jacobsen, Richard T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of Optical Fiber Bandwidth in the Frequency Domain

Description: Abstract: The design, evaluation, and performance of a system for determining the magnitude of the transfer function (hence, the bandwidth) of a multimode optical fiber are presented. The system operates to about 1450 MHz using a tracking generator/spectrum analyzer combination for narrowband detection. It is constructed, almost entirely, from commercially available components. The system is less complex and easier to use than an equivalent time domain system and the measurement precision is co… more
Date: September 1981
Creator: Day, G. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermophysical Properties of Isobutane from 114 to 700 K at Pressures to 70 MPa

Description: Abstract: Using a modified version of the nonanalytic equation of state, thermophysical properties of isobutane are derived from physical properties data and are tabulated at integral temperatures over the entire range of fluid states from 114 to 700 K along isobars at pressures to 70 MPa. Results include dielectric constants, densities, enthalpies, entropies, equation of state, internal energies, isobars, isochores, isotherms, Joule-Thomson inversion, heats of vaporization, melting line, ortho… more
Date: January 1982
Creator: Goodwin, Robert D. & Haynes, William M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electrical Properties of Materials and Their Measurement at Low Temperatures

Description: Abstract: A review is given of the electrical resistance of materials at cryogenic temperatures. Measurement techniques, the data base, and uses of the data are presented. The emphasis is on metals and alloys of technological importance; a toxic which covers a large range of materials. Similarly, the treatment of theory and of measurement techniques is primarily for the user interested in the more practical aspects of the subject. In every instance, however, references are given which allow the… more
Date: March 1982
Creator: Fickett, F. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Possible Estimation Methodologies for Electromagnetic Field Distributions in Complex Environments

Description: Abstract: The problem of measuring and characterizing complicated multiple-source, multiple-frequency electromagnetic environments is becoming more important and more difficult as electrical devices proliferate. This paper outlines three general approaches to the problem which are currently under investigation at the National Bureau of Standards. The three approaches are: 1) a statistical treatment of the spatial distribution of electromagnetic field intensities, 2) a numerical computation usin… more
Date: March 1985
Creator: Kanda, Motohisa; Randa, J. & Nahman, N. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Near-Field Array of Yagi-Uda Antennas for Electromagnetic Susceptibility Testing

Description: Abstract: In electromagnetic susceptibility testing of electronic equipment, the ideal incident field is a plane wave. To approximate this condition, a seven-element array of Yagi-Uda antennas has been constructed and tested at a frequency of 500 MHz. The element weightings are determined by a near-field synthesis technique which optimizes the uniformity of the field throughout a rectangular test volume in the near field of the array. The amplitude and phase of the electric field have been meas… more
Date: June 1985
Creator: Hill, David A. & Koepke, Galen H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Radio-Frequency Power Delivery System: Procedures for Error Analysis and Self-Calibration

Description: Abstract: An expression is developed for net power delivered to a load in terms of the indicated forward and reflected power and the system S-parameters and reflection coefficients. The dual directional coupler is treated as nonideal with power reflections assumed between all ports. The system itself is used to evaluate the major S-parameter terms in net power computation, and uncertainty in the computed power is derived from origins in the power meter readings and incompletely known S-paramete… more
Date: August 1985
Creator: Kanda, Motohisa & Orr, R. David
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design of the National Bureau of Standards Isotropic Magnetic Field Meter (MFM-10) 300 kHz to 100 MHz

Description: From introduction: In this report the following will he discussed: (1) design consideration of the broadband magnetic field sensor, (2) overall design of the magnetic field meter, (3) performance of the meter, (4) calibration and operating procedures, (5) alignment and adjustment procedures, and (6) summary and conclusions.
Date: October 1985
Creator: Cruz, J. E.; Driver, L. D. & Kanda, Motohisa
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Theory of Mutual Impedances and Multiple Reflections in an N-Element Array Environment

Description: Abstract: A general theoretical approach is formulated to describe the complex electromagnetic environment of an N-element array. The theory reveals the element-to-element interactions and multiple reflections within the array. From the formulation, it is found that the interaction between an excited element and an open-circuited element can be viewed as the sum of terms describing all possible signal paths within the array environment which start from the radiating element and terminate on the… more
Date: February 1985
Creator: Muth, Lorant A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tables of Industrial Gas Container Contents and Density for Oxygen, Argon, Nitrogen, Helium, and Hydrogen

Description: Abstract: Custody transfer tables are presented for oxygen, argon, nitrogen, helium, and hydrogen. The tables are based on standard reference data previously compiled by the National Bureau of Standards. Two sets of tables are provided for each fluid. Tables in engineering units cover the range -40 to 130*F with pressures from 100 to 10,000 prig. Tables in SI units (density versus pressure and temperature) cover the range 200 to 370 K with pressures from 0.5 to 70 MPa. The tables in engineering… more
Date: June 1985
Creator: Younglove, Ben A. & Olien, Neil A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Redefining the Scratch Standards

Description: The following report describes scratch standards--a cosmetic standard--and studies on etched gratings that were made to replace submasters and redefine scratch standards.
Date: February 1985
Creator: Young, Matt & Johnson, Eric Gunnar, (Jr.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Shielded Balanced and Coaxial Transmission Lines: Parametric Measurements and Instrumentation Relevant to Signal Waveform Transmission in Digital Service

Description: Abstract: A method is presented for determining the impulse and step responses of a shielded cable using time domain terminal measurements and a physically based mathematical model for the transmission line properties of the cable. The method requires a computer controlled time domain measurement system and was implemented using the NBS Automatic Pulse Measurement System (APMS). Data are also developed for the frequency domain complex propagation function (attenuation and its related minimum-ph… more
Date: June 1981
Creator: Gans, William L. & Nahman, N. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Characterization of Optical Fiber Waveguides: A Bibliography with Abstracts, 1970-1980

Description: Abstract: This bibliography contains approximately 450 citations of papers concerning the characterization of optical fiber waveguides. Papers from scientific journals, trade journals and conferences are included along with book chapters. The citations of organized by parameter measured and measurement method. Where published abstracts are available they are included.
Date: June 1981
Creator: Day, G. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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WR 10 Millimeter Wave Microcalorimeter

Description: Abstract: A microcalorimeter has been built in WR 10 waveguide, 75-110 GHz, to serve as a power standard at the National Bureau of Standards (NBS). Included here is an evaluation of the errors in using the microcalorimeter for the measurement of effective efficiency of bolometer mounts. The error analysis shows a systematic uncertainty of +/- .83 percent and a random uncertainty of .37 percent.
Date: June 1981
Creator: Weidman, Manly P. & Hudson, Paul A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Review of Supercritical Fluid Extraction

Description: Forward: The purpose of this report is to summarize the results obtained from a brief investigation of supercritical fluid extraction principles and applications. This study was one portion of a project funded by the U.S. Department of Energy, Office of Fossil Energy, contract nuriber DE-AI01076PR06010, in response to a preliminary proposal submitted by the authors. This report sometimes uses company trade naries to identify processes and patent holders. This usage implies no endorsement by HBS… more
Date: December 1983
Creator: Ely, James F. & Baker, Jolene K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Error Analysis for the Use of Presently Available Lunar Radio Flux Data in Broadbeam Antenna-System Measurements

Description: From introduction: Simple, precise expressions for lunar diameter, average brightness temperature, flux density, and shape factor are presented. An analysis of the relationship between these parameters and corresponding errors are included. For broadbeam (HPBW>d) antennas, results show that flux density and shape factor can be determined with errors less than 13 percent and 0.4 percent respectively at frequencies below 10 GHz. Extension of the analysis to higher frequencies is indicated.
Date: February 1984
Creator: Daywitt, William C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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