High Efficiency E-band Power Amplifier and Transmitter in 55nm BiCMOS

Elham Rahimi-Takami, PhD
Scientist RF Architecture & Design
JKU Linz
Altenberger Straße 69
4040 Linz
Freitag, 25.10.2019

On October 25th, Elham Rahimi-Takami, RF Architecture & Design scientist, is going to talk about the changing requirements for mobile network structures by introducing an idea which improves the power efficiency.


Abstract: The mobile network structure is going to change drastically in the next years to handle the growing needs for the new standards and applications. Consequently, the backhaul, i.e. the links connecting base stations to the central network, will undergo several modifications to allow higher performances in terms of speed, number of users and good quality of service. The power amplifier is the most power-hungry block of an E-band transmitters for backhauling. This presentation introduces an idea which improves the power efficiency with emphasis in back-off region (i.e. when the power amplifier delivers output power lower than the peak value). It exploits a common-base transistor in the output stage, where the BE junction performs current-clamping to adjust the average (DC) current according to the actual output power. Two prototypes for E-band PAs and one prototype on E-band transmitter, which employs the proposed PA, have been realized in 55nm SiGe-BiCMOS technologies in the analog integrated circuit laboratory of the University of Pavia, demonstrating performances beyond the state-of-the-art.


Elham Rahimi received the B.Sc. degree in electrical engineering from the K. N. Toosi University of Technology, Tehran, Iran, in 2011, the M.Sc. degree in electrical engineering from the Amirkabir University of Technology, Tehran, in 2014, and the Ph.D. degree in microelectronics from the University of Pavia, Pavia, Italy, in 2019. Her Ph.D. dissertation was focused on high-efficiency millimeter-wave power amplifiers and direct-conversion transmitter for 5G networks. From 2012 to 2014, she was a Research Assistant with IC-Design Lab, Tehran Polytechnic, Tehran, where she is involved in sensor interfaces for biomedical applications with particular emphasis on SAR ADC. Her main research interests include analysis and design of RF/millimeter-wave BiCMOS/CMOS building blocks.