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Search Publications by: Timothy A. Hall (Fed)

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Displaying 1 - 15 of 15

RF Dataset of Incumbent Radar Signals in the 3.5 GHz CBRS Band

December 17, 2019
Author(s)
Raied Caromi, Michael R. Souryal, Timothy Hall
This Radio Frequency (RF) dataset consists of synthetically generated waveforms of incumbent 3.5 GHz radar systems. The intended use of the dataset is for developing and evaluating detectors for the 3.5 GHz Citizens Broadband Radio Service (CBRS) or

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

Modeling and Simulation Analysis of the Physical Sidelink Shared Channel (PSSCH)

May 24, 2018
Author(s)
David W. Griffith, Fernando J. Cintron, Timothy Hall, Richard A. Rouil
This paper examines the performance of the Long Term Evolution (LTE) Physical Sidelink Shared Channel (PSSCH) in out-of-coverage (OOC) device-to-device (D2D) communication scenarios. We develop a closed form expression for the distribution of the number of

Dynamic Spectrum Access Algorithms Based on Survival Analysis

December 20, 2017
Author(s)
Timothy Hall, Anirudha Sahoo, Robert C. Hagwood, Sarah B. Streett
In this study, we design and implement two algorithms for dynamic spectrum access (DSA) that are based on survival analysis. They use a non-parametric estimate of the cumulative hazard function to predict the remaining idle time available for secondary

3.5 GHz Environmental Sensing Capability Detection Thresholds and Deployment

September 1, 2017
Author(s)
Thao Nguyen, Anirudha Sahoo, Michael R. Souryal, Timothy Hall
Spectrum sharing in the 3.5~GHz band between commercial and government users along U.S. coastal areas depends on an Environmental Sensing Capability (ESC)---that is, a network of radio frequency sensors and a decision system---to detect the presence of

3.5 GHz Environmental Sensing Capability Sensitivity Requirements and Deployment

March 5, 2017
Author(s)
Thao T. Nguyen, Anirudha Sahoo, Michael R. Souryal, Timothy Hall
Spectrum sharing in the 3.5 GHz band between commercial and government users along U.S. coastal areas depends on an Environmental Sensing Capability (ESC), a network of radio frequency sensors and a decision system, to detect the presence of incumbent

The Importance of Entropy to Information Security

February 3, 2014
Author(s)
Apostol T. Vassilev, Timothy Hall
The strength of cryptographic keys is an active challenge in academic research and industrial practice. In this paper we discuss the entropy as fundamentally important concept for generating hard-to-guess, i.e., strong, cryptographic keys and outline the