2019 Seminars

Spring 2019

Date: February 8, 2019

Speaker:  Joel Kees, Virginia Tech

Title: "Robust Blind Spectral Estimation in the Presence of Impulsive Noise"

Abstract: Robust nonparametric spectral estimation involves generating an accurate estimate of the Power Spectral Density (PSD) for a given set of data while trying to minimize the bias due to data outliers. This is applied in the domain of electrical communications and digital signal processing when a PSD estimate of the electromagnetic spectrum is desired (often for the goal of signal detection), and when the spectrum is also contaminated by Impulsive Noise (IN). Power Line Communication (PLC) is an example of a communication environment where IN is a concern because power lines were not designed with the intent to transmit communication signals. There are many different noise models used to statistically model different types of IN, but one popular model that has been used for PLC and various other applications is called the Middleton Class A model, and this model is extensively used in this thesis. The performance of two different nonparametric spectral estimation methods are analyzed in IN: the Welch method and the multitaper method. These estimators work well under the common assumption that the receiver noise is characterized by Additive White Gaussian Noise (AWGN). However, the performance degrades for both of these estimators when they are used for signal detection in IN environments. In this thesis, basic robust estimation theory is used to modify the Welch and multitaper methods in order to increase their robustness.    

Bio: Joel Kees is graduating with a Master of Science in electrical engineering under Dr. Beex. He received his undergraduate degree from Virginia Tech. In the spring, he will begin working full-time for LGS innovations in Northern Virginia. In his free time, he likes to read and mountain unicycle.  


Date: February 1, 2019

Speaker:  Dr. Charles Clancy, Virginia Tech Hume Center

Title: Security and Privacy for the 5G Core Network

Abstract: 5G introduces many new features, including new Radio Access Network (RAN) protocols to support higher data rates.  However, many of the exciting new features of 5G are within the core network.  Completely re-envisioned as a microservices architecture that can be elastically deployed within a cloud environment, 5G goes head-first into the world of Software-Defined Networking (SDN) enabled by Network Function Virtualization (NFV).  Using this toolbox, 5G introduces the concept of network slicing which allows vertical integration of networking services with the cloud and the ability to elastically deploy services.  This talk will provide a tutorial of these new features within 5G, with a specific focus on security and privacy issues associated with them. 

Bio: Dr. Charles Clancy is the Executive Director of Virginia Tech's Hume Center for National Security and Technology and is the Bradley Professor of Electrical and Computer Engineering. With 85 faculty and staff, the Hume Center engages over 400 students annually in research and experimental learning focused in national security and technology. Dr. Clancy is an internationally-recognized expert at the intersection of wireless, cybersecurity, and artificial intelligence.

Prior to joining Virginia Tech in 2010, he served as a researcher at the National Security Agency. Dr. Clancy received his BS in Computer Engineering from the Rose-Hulman Institute of Technology, MS in Electrical Engineering from the University of Illinois, and PhD in Computer Science from the University of Maryland. He is a Senior Member of the IEEE and has over 200 peer-reviewed technical publications and patents, is co-author to five books, and co-founder to four venture-backed startup companies.