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Search Publications

NIST Authors in Bold

Displaying 176 - 200 of 610

Optimal Dynamic Spectrum Access Scheme for Utilizing White Space in LTE Systems

April 15, 2019
Author(s)
Anirudha Sahoo, Timothy Hall, Robert C. Hagwood
In this study, we design and implement an algorithm for optimal dynamic spectrum access (DSA) in a shared spectrum system where the primary user (PU) is a Long Term Evolution (LTE) system. The cumulative hazard function from survival analysis is used to

A New Perspective on an Old Problem: Scattering by a Perfect Electric Conductor

April 14, 2019
Author(s)
Alexey J. Yuffa, Johannes Markkanen, Qiang Sun, Evert Klaseboer, Derek Y. Chan
We explore several different singular surface integral equation formulations. These formulations are specifically designed for time-harmonic scattering by a perfect electric conductor and are obtained by choosing non-conventional boundary unknowns.

Indoor Localization Accuracy of Major Smartphone Location Apps

April 14, 2019
Author(s)
Nader Moayeri, Chang Li, Lu Shi
NIST carried out comprehensive testing in five large buildings to evaluate the accuracy of Fused Location Provider (FLP) Application Programming Interface (API) running on Android phones with that of Core Location Framework running on iPhones. The testing

System Distortion Model for the Cross-Validation of Millimeter-Wave Channel Sounders

March 31, 2019
Author(s)
Camillo Gentile, Andreas Molisch, Jack Chuang, Anuraag Bodi, Anmol Bhardwaj, Ozgur Ozdemir, Ismail Guvenc, Zihang Cheng, Thomas Choi, Robert Mueller
Because millimeter-wave directional channel measurements are time-consuming and expensive to collect, there is considerable interest in combining measurement data obtained with different channel sounders in order to yield more comprehensive datasets. The

Interlaboratory Millimeter-Wave Channel Sounder Verification

March 30, 2019
Author(s)
Jeanne Quimby, David G. Michelson, Mustapha Bennai, Kate Remley, Joshua Kast, Alec Weiss
The channel sounder verification program within the National Institute of Standards and Technology-coordinated 5G mmWave Channel Model Alliance aims to place channel sounders on a sound metrological foundation by using well-established laboratory

Channel Characterization and Delay Optimization for Industrial Wireless Control Systems

March 4, 2019
Author(s)
Xiaolin Jiang, Zhibo Pang, Rick Candell, Dacfey Dzung, Michele Luvisotto, Carlo Fischione
Wireless communication is gaining popularity in industry for its simple deployment, mobility and low cost. Ultra low latency and high reliability requirements of mission critical industrial applications are highly demanding for wireless communication, and

Let’s Keep Women in Microwaves

March 1, 2019
Author(s)
Catherine A. Remley
This is a column for the "Women in Microwaves" affinity group of the IEEE Microwave Theory and Techniques Society, to be published in IEEE Microwave Magazine. The column discusses the well documented effect that after ten years or so into a science

Methodology for Multipath-Component Tracking in Millimeter-Wave Channel Modeling

March 1, 2019
Author(s)
Chiehping Lai, Roy Sun, Camillo Gentile, Peter B. Papazian, Jian Wang, Jelena Senic
In this paper, we describe an extensive channel-measurement campaign - including 325 unique transmitter-receiver configurations - conducted in a lecture room with our 3D double- directional 60-GHz channel sounder. The receiver was mounted on a mobile robot

Portable Verification Artifact for Millimeter-Wave-Frequency Channel Sounders

March 1, 2019
Author(s)
Jos N. Dortmans, Jeanne Quimby, Kate Remley, Dylan Williams, Jelena Senic, Roy Sun, Peter B. Papazian
We develop a portable artifact for the conducted verification of millimeter-wave-frequency channel sounders. The artifact is first characterized with a vector network analyzer, providing a high-dynamic range, traceable measurement and complete uncertainty

Mobile Device Security: Cloud and Hybrid Builds

February 21, 2019
Author(s)
Christopher J. Brown, Spike E. Dog, Sallie P. Edwards, Neil C. McNab, Matt Steele, Joshua M. Franklin
This document proposes a reference design on how to architect enterprise-class protection for mobile devices accessing corporate resources. The example solutions presented here can be used by any organization implementing an enterprise mobility management

Performance Assessment of Smart Meter Traffic over LTE Network Using SDR Testbed

February 18, 2019
Author(s)
Amirshahram Hematian, Wei Yu, David W. Griffith, Nada T. Golmie
In the smart grid, a variety of smart meters will be deployed to support diverse services, such as energy distribution management, grid monitoring and management, and the integration of renewable energy resources. On the power distribution side, regular

Impedance tuning with photoconductors to 40 GHz

January 22, 2019
Author(s)
Jasper A. Drisko, Ari D. Feldman, Franklyn J. Quinlan, James C. Booth, Nathan D. Orloff, Christian J. Long
Light has been widely used to control a variety of microwave devices, including switches, antennas, and detectors. Here, we present a photoconductive device integrated into a coplanar waveguide to tune complex impedances at microwave frequencies with

A User Application-Based Access Point Selection Algorithm for Dense WLANs

January 16, 2019
Author(s)
Munsuk Kim, Ye Na Kim, Sukyoung Lee, Nada T. Golmie, SeungSeob Lee
The current commercial access point (AP) selection schemes are mostly based on signal strength, but perform poorly in many situations because they ignore the actual load distributions among the APs. To address this shortcoming, a number of alternative

Efficient MU-MIMO Beamforming Protocol for IEEE 802.11ay WLANs

January 1, 2019
Author(s)
Munsuk Kim, Tanguy Ropitault, SuKyoung Lee, Nada T. Golmie
IEEE 802.11ay supports multi-user multiple-input-multiple-output (MU-MIMO). However, the MU- MIMO BFT (Beamforming Training) is a time-consuming process to find appropriate directional antenna patterns, and inefficient BFT results in a long training time

Impact of Measurement Points Distribution on the Parameters of UWB Implant Channel Model

December 20, 2018
Author(s)
Kamran Sayrafian, Sofia Perez-Simbor, Katjana Krhac, Concepcion GarciaPardo, Dina Simunic, Narcis Cardona
Sophisticated medical implants that allow vital information delivery to/from the human body are opening the door to novel approaches in diagnosis and/or therapy of various health related issues. Ultra-Wide Band (UWB) technology is gaining the attention of

EMC and Metrology Challenges for 5G and Beyond

December 7, 2018
Author(s)
Perry F. Wilson, Catherine A. Remley, William F. Young, Camillo A. Gentile, John M. Ladbury, Dylan F. Williams
The potential to connect people and devices anywhere and anytime is driving the development and deployment of a multitude of wireless systems. Wireless connectivity is central to advanced communication technologies, the internet of things (IoT), the smart

Millimeter-Wave Channel Measurement and Modeling: A NIST Perspective

December 7, 2018
Author(s)
Camillo A. Gentile, Peter B. Papazian, Nada T. Golmie, Catherine A. Remley, Peter G. Vouras, Jelena Senic, Jian Wang, Jack Chuang, Ruoyu Sun
The exponential increase in wireless data transmission from smartphones has led to the saturation of the sub-6-GHz bands, forcing cellular providers to migrate to the millimeter-wave (mmWave) regime for 5G. Although available channel bandwidths will grow

Millimeter-Wave Propagation Channels vs. Synthetic Beamwidth

December 7, 2018
Author(s)
Roy Sun, Camillo A. Gentile, Jelena Senic, Peter G. Vouras, Peter B. Papazian, Nada T. Golmie, Catherine A. Remley
High-gain narrow-beam antennas or beamformed antenna arrays will likely be used in millimeter- wave (mmWave) bands and 5G to mitigate the high path loss. Since many multipath components may be excluded by the narrow beam, the mmWave propagation channels

Bringing Precision to Measurements for mmWave 5G Wireless

December 3, 2018
Author(s)
Catherine A. Remley
At millimeter-wave frequencies and for wide modulation bandwidths, the hardware performance of both modulated-signal sources and vector receivers becomes increasingly nonideal. These nonidealities make test and validation of devices, circuits and systems

A Possible Advantage of Using Bi-directional S-Parameters in Antenna Measurements

November 30, 2018
Author(s)
Alex Yuffa, Ronald C. Wittmann, Michael H. Francis, Josh Gordon, David R. Novotny
the unknown-thru calibration technique is being used to achieve a system level calibration at milli-meter frequencies (>50 GHz) on the robotic ranges at NIST. Since this requires the use of a full bi-directional measurement, which takes longer than
Displaying 176 - 200 of 610