The paper is entitled "A +27.3dBm Transformer-Based Digital Doherty Polar Power Amplifier Fully Integrated in Bulk CMOS," and the co-authors include Wang's Ph.D. students Song Hu and Jong Seok Park; Outmane Chlieh, a Ph.D. student advised by ECE Professor John Papapolymerou; and Shouhei Kousai, a senior design engineer at Toshiba Corporation. 

In the paper, the team proposed a novel digital Doherty polar power amplifier (PA) circuit architecture and implemented it in a standard 65 nm CMOS process. This architecture leverages digital reconfigurability and achieves optimum Doherty active load-modulation operation for maximum PA back-off efficiency enhancement and optimum AM-AM and AM-PM linearization. These desired properties enabled the wireless transmission of high data-rate with drastically enhanced efficiency, and extended battery life in mobile devices.

In addition, the team demonstrated that this digital Doherty architecture can be reconfigured to achieve robust PA performance against antenna load variations. This aspect of the design opens the door for in-field transmitter reconfiguration to ensure optimum wireless transmission under different or even time-varying radiation environments. This digital Doherty PA circuit architecture can also be further extended to other integrated circuit processes to address defense-related applications.

The work presented in this RFIC paper is sponsored by the Toshiba membership in the GEDC and by Toshiba's in-kind donations of CMOS multiproject wafer fabrication runs. 

***********************

Pictured in the photo left to right are Hua Wang, Wang's Ph.D. students Jong Seok Park and Song Hu (first author), and Lawrence Kushner of BAE Systems. Kushner served as the general conference chair for the 2014 IEEE RFIC.