Colloquium: Shubhendu Bhardwaj
Thursday, Oct. 19
Talk: 3:30–4:30 PM
Reception: 4:30–5 PM
115 Avery Hall
Dr. Shubhendu Bhardwaj
Assistant Professor of Electrical and Computer Engineering
University of Nebraska–Lincoln
"KHz to THz Antennas: Exploiting Radio Waves for Communication, Sensing and Wireless-Health"
Abstract: Application of radio-waves in wireless communication and healthcare relies on our ability to develop and integrate miniaturized RF systems on such platforms. Critical research is needed to effectively adapt antenna designs and connected RF systems towards such platforms. In this seminar talk, Dr. Bhardwaj will present his group’s research on developing such systems for identified applications. For battery free, wireless integration into wearable systems, two main challenges of (1) providing wireless power to the sensor system and (2) extracting sensor output data in a wireless form using a minimalistic circuit will be addressed. The presentation will discuss methods of wireless power transfer in an ergonomic setting to allow ease of use for wearable systems. Specifically, development and integration of smart bandages that are wirelessly powered and provide accurate electrochemical sensing of wound health will be discussed. Within these systems, a new antenna configuration and associated active-RFID system that allows extraction and transmission of signal will be presented. Another use case of wireless power is presented for providing trickle charge to mobile phones using far-zone electromagnetic signal to cover a larger region of space. In the next part of the presentation, the research will discuss implementing a low frequency antenna in the range of KHz to MHz range using multiferroic substrates. Due to large wavelength at such frequencies, compact design of antennas in this band is challenging. To address this issue, we investigate the use of piezoelectric and magnetostrictive materials to generate low frequency magnetic signals for sensing and communication applications. The final part of the presentation will discuss challenges and resolutions related to scaling antennas to sub-millimeter wave and terahertz frequency range. The presentation will discuss two specific innovative designs based on metal machining of antennas for compact high gain communication links.
Speaker Bio: Shubhendu Bhardwaj is Assistant Professor with Electrical and Computer Engineering department at University of Nebraska-Lincoln, USA. He completed his M.S. from UCLA, CA in 2012 and Ph.D. from The Ohio State University, Columbus, OH in 2017. Bhardwaj graduated summa cum laude from IIT (ISM)-Dhanbad with bachelor’s degree and he subsequently worked at Samsung India. His current and past research is funded by DARPA, Air-Force, NSF, NSF-ERC ASSIST, and other private entities. Dr. Bhardwaj has been involved in antenna design, optimization, fabrication, and measurements over the past 8 years, with experience in both academic and industrial settings, including previous work at Sony Ericsson Mobile. During his dissertation work, he won four best paper awards and a Presidential Fellowship. In his research work, he has worked on antenna designs for dual-polarized weather radar applications, slotted patch antennas, waveguide-based antennas in the 90-140 GHz frequency band, among many other associated areas. His work on novel phaseless gain characterization methods has won two best paper awards at URSI and AMTA conferences. He pioneered the design of one of the first septum-less CP horn antennas demonstrated beyond 90 GHz, using the concept of hexagonal waveguides, and is now patented. Beyond antennas, Dr. Bhardwaj has worked on aspects of electromagnetic modeling and design. He is recipient of best student paper awards at URSI-GASS-2017, IEEE-iWat-2017 and IEEE-AMTA-2015, 2014. Currently he is involved in research in applied electromagnetics and RF systems towards semiconductor devices, antennas, and wearable systems. He is also involved in computational electromagnetics based on neural networks for accelerated neuromorphic computational solvers.