Winners of the 2020 John D. and Alice Nelson Kraus Memorial Graduate Student Poster Competition Announced
The setting might be different this year, but the honor remains the same.
Winners of the 2020 John D. and Alice Nelson Kraus Memorial Graduate Student Poster Competition were announced this week..
The virtual event of The Ohio State University's Electrical and Computer Engineering graduate school research contributions was held between Aug. 10 and 24 and was organized by the Electrical and Computer Engineering graduate program and faculty judges.
Event organizer, Qudsia Tahmina, said having the poster competition go on virtually this year was important, in order to continue serving students the best way possible.
"This competition has encouraged our graduate students to overcome the anxiety due to the cancellation of several events and conferences this year. Successful completion of this competition proves that it is the motivation that matters and perseverance to achieve the goals," said Tahmina, an assistant professor of practice in electrical engineering. "I applaud student’s willingness to participate in this competition even with reduced research activities and lack of accessibility to their labs."
The first place winner of the competition, Manmeet Singh, took home top prize of $500 for his research, “A Digitally-Assisted Buck-Boost Converter with Seamless Mode Transitions and Fast Dynamic Response for Extending Battery Life in Mobile Devices.” Singh is advised by Professor Ayman Fayed.
According to Singh’s abstract, operating switching power converters from an input voltage as low as 2.3V in devices operating from Li-Ion batteries can extend the running time of the device by as much as 20% compared to the common practice of shutting down the device when the battery drops to 2.7V.
However, since many of these devices require power supplies that are higher than 2.3V but lower than the maximum voltage of a Li-Ion battery (i.e. 5V), designing these power converters becomes challenging. This work presents a noninverting buck-boost converter to address this challenge. The converter uses digital adaptive slew-rate control and hysteretic mode detection to achieve fast dynamic response and seamless/noise-immune mode transition between the buck, boost, and buck-boost modes of operation. The converter is fabricated in 0.13-μm CMOS, and supports 2.3–5V input and 1.5– 3.6V output. It achieves 91.7% peak efficiency and over 80% efficiency at 1-mA load across all conditions.
In second place, Jacob Compaleo won $300 for his work entitled, “Application of Sparse Representation to Bartlett Spectra for Improved Direction of Arrival Estimation.” His advisor is Professor Inder Gupta.
For decades, the abstract explains, obtaining accurate direction of arrival (DOA) estimation of the signals incident on an array of antenna elements has been an area of great interest. In this poster presentation, a new technique for high-resolution direction of arrival estimation is presented. The method utilizes the traditional Bartlett spectra and sparse representation to locate emitters in single and multiple emitter scenarios. Using Monte Carlo simulations, the work shows show an approach that achieves accurate DOA estimations that are unbiased and a variance that approaches the Cramer-Rao lower bound. This method outperforms the popular MUSIC algorithm when angular separation between emitters is small, signal SNR is low, and a small number of snapshots are used in DOA estimation.
Nidhin Kalarickal won third place and $100 in the competition this year for the research, “Electrostatic Engineering Using High Permittivity Materials for Ultra-wide Band Gap Transistors.” His advisor is Professor Siddharth Rajan.
Maintaining high average fields between the gate and drain terminals is imperative in achieving near theoretical performance in ultra-wide band gap semiconductors like 𝛽-Ga2O3. The research abstract explains how peak electric fields occurring at the corner of gate/field plate makes this highly challenging. The paper reports on a field management strategy to reduce the peak electric field at the drain side corner of the gate by using a composite dielectric layer consisting of a high-k/low-k heterojunction overlapped over the gate electrode. Utilizing this strategy in 𝛽-Ga2O3 modulation doped double heterojunction field effect transistor, helped achieve a record average breakdown field of 5.7 MV/cm at a gate-drain spacing of 1.15 um along with an improved power figure of merit of 586 MW/cm2. The reported work shows the effectiveness of integrating high-k dielectrics with ultra-wide band gap materials in significantly improving breakdown performance.
"Judges have been tremendously helpful in evaluating posters and video presentations and providing valuable feedback. All-in-all, it was a unique and fun experience this year and I look forward to the future competitions," Tahmina said.
Find the full breakdown of participants and research presented this year in the 2020 Program: