A Compact 40-GHz Doherty Power Amplifier With 21% PAE at 6-dB Power Back Off in 0.1-mu m GaAs pHEMT Process
Journal
Ieee Microwave and Wireless Components Letters
Journal Volume
29
Journal Issue
8
Pages
545-547
Date Issued
2019
Author(s)
Abstract
This letter presents a monolithic 40-GHz Doherty power amplifier (PA) fabricated in 0.1-μm depletion mode (D-mode) gallium arsenide (GaAs) pseudomorphic high electron mobility transistor process. Different from most Doherty PAs, this PA occupies a compact chip size of 2.25 mm 2 because of the power-combining techniques. The measured results show a small signal gain of 12.7 dB, an output 1-dB compression point (OP 1 dB ) of 19.2 dBm and saturated output power (P sat ) of 23.1 dBm at 40 GHz. Meanwhile, this PA achieves peak power added efficiency (PAE) of 28.5% and PAE of 21.1% at 6-dB power back off (PBO) from P sat . Finally, the bandwidth of this well-improved backed-off efficiency is obtained from 39 to 41 GHz with an output third-order intercept point (OIP 3 ) of 20 dBm. Among published Ka-band GaAs Doherty PAs, this work exhibits the best 6-dB backed-off efficiency around 38 GHz, supporting the upper-frequency band for 5G wireless systems.
SDGs
Type
journal article