Programação >> David J. Allstot Palestrante David J. Allstot, Sudip Shekhar and Jeffrey Walling - (Dept. of Electrical Engineering University of Washington) Título Improving efficiency in CMOS Power Amplifiers and Transmitters Resumo Fully-integrated CMOS power amplifiers (PAs) have limited performance, inhibiting their use in high-performance transmitters. Poor quality factor (Q) inductors and low transistor breakdown voltages cause the PA to suffer in terms of output power (Pout) and power-added efficiency (PAE). The desire for complete system-on-chip integration is driving research to explore non-traditional techniques which take advantage of CMOS strengths at the circuit and the architecture level. Recent advances in power combination structures, such as spiral transformers and distributed active transformers (DATs), have allowed efficient combination of several low output power PAs to produce significant improvements in Pout and PAE. Non-linear switching PAs offer improvements in PAE. However, they also have limited sensitivity to input envelope fluctuation, and thus cannot be used by themselves for varying-envelope modulations such as QAM and OFDM. Techniques such as envelope elimination and restoration (EER), pulse width modulation (PWM) and outphasing offer envelope restoration with minimal external circuitry. These techniques not only exploit switching PAs, but can also exploit direct phase modulation of a PLL in order to remove external channel filtering. Biografia Resumida David J. Allstot (S'72-M'72-SM'83-F'92) received the B.S. degree from the University of Portland, Portland, OR, the M.S. degree from Oregon State University, Corvallis, and Ph.D. degree from the University of California, Berkeley. He has held several industrial and academic positions and has been the Boeing-Egtvedt Chair Professor of Engineering at the University of Washington, Seattle, since 1999. He has advised approximately 100 M.S. and Ph.D. graduates and published more than 250 papers. Dr. Allstot has received several outstanding teaching and advising awards. Other awards include the 1978 IEEE W.R.G. Baker Prize Paper Award, 1995 IEEE Circuits and Systems Society (CAS-S) Darlington Award, 1998 IEEE Int. Solid-State Circuits Conf. (ISSCC) BeatriceWinner Award, 1999 IEEE CAS-S Golden Jubilee Medal, 2004 Technical Achievement Award of the IEEE CAS-S, the 2005 Aristotle Award of the Semiconductor Research Corp, and the 2008 University Research Award of the Semiconductor Industries Association. He was an Associate Editor of the IEEE TRANSACTIONS ONCIRCUITS AND SYSTEMS II: ANALOG AND DIGITAL SIGNAL PROCESSING from 1990 to 1993 and the Editor-in-Chief from 1993 to 1995. He was on the Technical Program Committee, IEEE Custom Integrated Circuits Conference, from 1990 to 1993, Education Award Committee, IEEE CAS-S, from 1990 to 1993, Board of Governors, IEEE CAS-S, from 1992 to 1995, Technical Program Committee, IEEE International Symposium on Low-Power Electronics and Design, from 1994 to 1997, Mac Van Valkenberg Award Committee, IEEE CAS-S, from 1994 to 1996, and Technical Program Committee, IEEE ISSCC, from 1994 to 2004. He was the 1995 Special Sessions Chair, IEEE International Symposium on CAS (ISCAS), an Executive Committee Member and the Short Course Chair, ISSCC, from 1996 to 2000, Co-Chair, IEEE Solid-State Circuits (SSC) and Technology Committee, from 1996 to 1998, Distinguished Lecturer, IEEE CAS-S, from 2000 to 2001, Distinguished Lecturer, IEEE SSC Society, from 2006 to 2007, the Co-General Chair, IEEE ISCAS in 2002 and in 2008, and President-Elect, IEEE CAS-S, 2008.