Abstract:
This seminar presents recent advances and future trends in power amplifier and RF
transmitter research with applications to wireless communication technology. The first part of the
talk gives an overview of state-of-the-art techniques for efficiency and linearity enhancement in
the context of modern communication waveforms with wide bandwidth and highly varying signal
envelopes. Advanced concepts such as load modulation, harmonic tuning, and digital
predistortion are explained in this section. My contributions to advancing the state-of-the-art in
these areas are then presented in the second part of the seminar. Particularly, high-impact
research contributions that have led to 1) renovating the concept of input waveform shaping, 2)
transforming the design of inverse class-F power amplifiers, and 3) advancing the technology of
mixed-signal Doherty transmitter systems are discussed. The third part of the seminar highlights
the areas of research focus that I would like to address in the future. In addition to discussing
original research directions relating to advanced power amplifier and RF transmitter architectures,
this section also identifies new opportunities for transposing our know-how in RF power research
to other applications relating to the areas of wireless energy harvesting and flexible analog
electronics.
Bio:
Dr. Ramzi Darraji received the Ph.D. degree in electrical and computer engineering from the
University of Calgary in 2013. He is currently with Ericsson Canada (Ottawa) pursuing research
and product development for RF transmitter architectures, advanced power amplifier design, and
radio transceiver linearization in support of cellular and wireless communication technology. He
has successfully transferred several designs from early systemization to volume rollout and
received the 2021 Above & Beyond Award for outstanding contributions in research and
technological innovation at Ericsson. Prior to that, he has held the Natural Sciences and
Engineering Research Council of Canada (NSERC) postdoctoral fellowship at the University of
Alberta. Dr. Darraji is generally interested in innovating the design of mixed-signal, RF, and mm-
Wave integrated circuits and systems for wireless communication applications. He has authored
or co-authored over 50 referred publications and holds 3 U.S. patents in this area.