Theory, Design and Implementation of Energy-Efficient Biotelemetry using Ultrasound Imaging

This dissertation investigates the fundamental limits of energy dissipation in establishing a communication link with implantable medical devices using ultrasound imaging-based biotelemetry. Ultrasound imaging technology has undergone a revolution during the last decade due to two primary innovations: advances in ultrasonic transducers that can operate over a broad range of frequencies and progresses in high-speed, high-resolution analog-to-digital converters and signal processors. Existing clinical and FDA approved bench-top ultrasound systems cangenerate real-time high-resolution images at frame rates as high as 10000 frames per second. On the other end of the spectrum, portable and hand-held ultrasound systems can generate high-speed real-time scans, widely used for diagnostic imaging in non-clinical environments. This dissertation’s fundamental hypothesis is to leverage the massive data acquisition and computational bandwidth afforded on these devices to establish energy-efficient bio-telemetry links with multiple in-vivo implanted devices. In the first part of the dissertation, I investigate using a commercial off-the-shelf (COTS) diagnostic ultrasound reader to achieve reliable in-vivo wireless telemetry with millimeter-sized piezoelectric crystal transducers. I propose multi-access biotelemetry methods in which several of these crystals simultaneously transmit the data using conventional modulation and coding schemes. I validated the feasibility of in-vivo operation using two piezoelectric crystals tethered to the tricuspid valve and the skin’s surface in a live ovine model. I demonstrated data rates close to 800 Kbps while consuming microwatts of power even in the presence of respiratory and cardiac motion artifacts. In the second part of the dissertation, I investigate the feasibility of energy harvesting from cardiac valvular perturbations to self-power the wireless implantable device. In this study, I explored using piezoelectric sutures implanted in proximity to the valvular regions compared to the previous studies involving piezoelectric patches or encasings attached to the cardiac or aortic surface to exploit nonlinearity in the valvular dynamics and self-power the implanted device. My study shows that power harvested from different annular planes of the tricuspid valve could range from nano-watts to milli-watts. In the final part of this dissertation, I investigate beamforming in B-scan ultrasound imaging to further reduce the biotelemetry energy-budget. In this context, I will study variance-based informatics in which the signal representation takes a form of signal variance instead of the signal mean for encoding and decoding. Using a modeling study, I show that compared to the mean-based logic representation, the variance-based representation can theoretically achieve a superior performance trade-off (in terms of energy dissipation) when operating at fundamental limits imposed by thermal-noise. I will then discuss how to extend variance-based representation to higher signal dimensions. I show that when applying variance-based encoding/decoding to B-scan biotelemetry, the power-dissipation requirements can be reducedto 100 pW even while interrogating from depths greater than 10 cm in a water medium

2019 Cybersecurity Research Transition to Practice Workshop Poster Session

Poster session from the Trusted CI 2019 Cybersecurity Research Transition to Practice Workshop. Ahmet Okutan, Rochester Institute of Technology, Research Faculty * CyberMPS: Cyberattack, Modeling, Prediction, and Simulation Vafa Andalibi, Indiana University * Securtle for Cyber Defense * Defending IoT devices and Edge network with Manufacturer Usage Description DongInn Kim, Indiana University * Defending against Man In The Middle (MITM) Attacks at the Edge Pablo Moriano, Indiana University, PhD * Insider Threat Mitigation Olivia Kenny, Indiana University * Who’s Watching Your Child? * The Overly Friendly Crockpot Joshua Streiff, Indiana University * Why Johnny Doesn’t Use Two Factor Steve Jan, Virginia Tech * Connecting the Digital and Physical World for Adversarial Attacks Sri Harsha Kondapalli and Darshit Mehta, Washington University in St. Louis * Zero-powered Dynamic Authentication based on Quantum Tunneling TimersNSF #1547272Ope

2019 Cybersecurity Research Transition to Practice Workshop Poster Session

Poster session from the Trusted CI 2019 Cybersecurity Research Transition to Practice Workshop. Ahmet Okutan, Rochester Institute of Technology, Research Faculty * CyberMPS: Cyberattack, Modeling, Prediction, and Simulation Vafa Andalibi, Indiana University * Securtle for Cyber Defense * Defending IoT devices and Edge network with Manufacturer Usage Description DongInn Kim, Indiana University * Defending against Man In The Middle (MITM) Attacks at the Edge Pablo Moriano, Indiana University, PhD * Insider Threat Mitigation Olivia Kenny, Indiana University * Who’s Watching Your Child? * The Overly Friendly Crockpot Joshua Streiff, Indiana University * Why Johnny Doesn’t Use Two Factor Steve Jan, Virginia Tech * Connecting the Digital and Physical World for Adversarial Attacks Sri Harsha Kondapalli and Darshit Mehta, Washington University in St. Louis * Zero-powered Dynamic Authentication based on Quantum Tunneling TimersNSF #1547272Ope