Low Power RF Circuits for Broadband Signals

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Friday, February 22, Kemper 1065, 9:00am-11:00am

Speaker: Ramesh Harjani
University of Minnesota

Host: Professor Subhash Mahajan


We continue our insatiable desire for increased wireless bandwidth while making our portable devices smaller and lighter weight. Though not optimally used, the majority of wireless spectrum has been pre-allocated using inefficient static spectrum policies. Cognitive radios can dynamically reconfigure hardware and software to accommodate different frequencies, and protocols leading to more efficient use of the spectrum. However, spectrum sensing is one of the critical aspects of cognitive radios that require instantaneous wide bandwidth. But handling wide bandwidths increases power consumption substantially. In this talk we focus on low power analog/RF wideband signal processing techniques that overcome the power bottleneck. In particular, we present a passive switched-capacitor analog FFT that is used to reduce data converter power and also describe a multi-beam wideband phased array.


Ramesh Harjani is the E.F. Johnson Professor of Electronic Communications in the Department of Electrical & Computer Engineering at the University of Minnesota. He is a Fellow of the IEEE. He received his Ph.D. in Electrical Engineering from Carnegie Mellon University in 1989. He was at Mentor Graphics, San Jose before joining the University of Minnesota. He has been a visiting professor at Lucent Bell Labs, Allentown, PA and the Army Research Labs, Adelphi, MD. He co-founded Bermai, Inc, a startup company developing CMOS chips for wireless multi-media applications in 2001. His research interests include analog/RF circuits for wired and wireless communication systems.

Dr. Harjani received best paper awards at the 1987 DAC, 1988 ICCAD, the 1998 GOMAC and the 2007, 2010 & 2012 TECHCON. His papers have been recognized as one of the most influential in the first 25 years of DAC and the Best of ICCAD. His research group won 1st prize for the SRC Design Challenges in 2000 and 2003. He is an author/editor of four books. He was an Associate Editor for IEEE Transactions on Circuits and Systems Part II, 1995-1997, Guest Editors for the International Journal of High-Speed Electronics and Systems and for Analog Integrated Circuits and Signal Processing in 2004 and a Guest Editor for the IEEE Journal of Solid-State Circuits, 2009-2011. He is currently a Senior Editor for the IEEE Journal on Emerging & Selected Topics in Circuits & Systems (JETCAS), 2011-2013 and the Technical Program Chair for the IEEE Custom Integrated Circuits Conference. He was the Chair of the IEEE Circuits and Systems Society technical committee on Analog Signal Processing from 1999 to 2000 and a Distinguished Lecturer of the IEEE Circuits and Systems Society for 2001-2002.