Dr. Waleed Khalil received his BS and MS degrees from the University of Minnesota in 1992 and 1993, respectively, and his PhD degree from Arizona State University in 2008. He is currently serving as an Associate Professor at the ECE department and the ElectroScience Lab, The Ohio State University. He also serves as Co-Director of the Air Force Center of Excellence for Enabling Cyber Defense in Analog and Mixed Signal Domain (CYAN) and The National MicroElectronics Security Training Center (MEST). Prior to joining OSU in 2009, he spent 16 years at Intel Corporation where he held various positions in wireless and wireline communication groups. His group’s research is focused on integrated circuits and systems, with applications in the areas of wireless communications, hardware security, heterogeneous integration, high-speed interconnects, and image sensors. He is the recipient of OSU’s College of Engineering Lumley Research Award and Fred H. Pumphrey’s Distinguished Teacher Award. His research group has received several paper awards, among them TSMC’s outstanding research award and best paper awards in several conferences. He authored 16 issued and several other pending patents, over 100 journal and conference papers and three books/book chapters. He is a senior member of IEEE and served as an Associate Editor for the Journal of Solid State Circuits (JSSC) and the general chair for the 2020 RFIC Symposium. He is currently serving as the Editor-in-Chief for the IEEE RFIC Virtual Journal (RFIC-VJ).
The ever-increasing demand for data rates/range in modern communication/radar systems coupled with the push towards mm-wave links, has dictated the need for wide tuning range voltage controlled oscillators (VCOs). Nowadays, mm-wave circuits have proliferated into many commercialized applications, including next generation WiFi, auto short range radar (SRR), satellite data and video and mm-wave cellular (LMDS). Traditionally, mm-wave VCOs have been implemented in III-V technologies benefiting from fast device speed and low parasitic capacitance. Therefore, VCOs can operate at mm-wave with reasonable tuning range. However, they suffer from the main drawback of high manufacturing cost and limited level of integration. With lower cost, high transistor fT, ease of integration and power-savings, silicon-based VCOs are very attractive for large-volume applications. Unfortunately, the benefits in digital CMOS technology are not perpetuated easily in designing mm-wave VCOs. The RF components, including inductors and capacitors, suffer from low Q-factor. Therefore, large transconductance (gm) transistors are required to compensate for high losses, leading to pronounced capacitive loading effects that sharply reduce the VCO tuning range. Moreover, transistors with large gm generate high switching noise in mm-wave, which significantly degrade the phase noise of the VCO. In light of these challenges, this talk will present our current research work to build robust Si-based RF circuits with focus on ultra wide tuning-range and low phase noise VCOs.