Title :
Investigation of the AM/pm distortion in Doherty Power Amplifiers
Author :
Piazzon, L. ; Giofre, R. ; Colantonio, P. ; Giannini, F.
Author_Institution :
E.E.Dept., Univ. of Roma Tor Vergata, Rome, Italy
Abstract :
In this paper, a theoretical investigation of the causes of the AM/PM distortion in Doherty Power Amplifiers is presented for the first time. The distortion sources are identified and a solution to mitigate the AM/PM conversion through the input termination of the Carrier amplifier is also highlighted. The relevant analysis is carried out using a simplified model of the active device and validated by means of full nonlinear model of a commercial GaN HEMT transistor. The role of the Miller effect in such a kind of distortion is stressed, demonstrating the existing link between output load modulation and phase distortion.
Keywords :
III-V semiconductors; distortion; gallium compounds; high electron mobility transistors; power amplifiers; wide band gap semiconductors; AM conversion; AM distortion; Doherty power amplifiers; GaN HEMT transistor; Miller effect; PM conversion; PM distortion; carrier amplifier; load modulation; phase distortion; Load modeling; Modulation; Nonlinear distortion; Phase distortion; Power amplifiers; Power generation; Solid modeling; AM/PM distortion; Doherty Amplifier; Load-Source Pull; power amplifiers;
Conference_Titel :
Power Amplifiers for Wireless and Radio Applications (PAWR), 2014 IEEE Topical Conference on
Conference_Location :
Newport Beach, CA
Print_ISBN :
978-1-4799-2298-7
DOI :
10.1109/PAWR.2014.6825729
