80-110-GHz Broadband Linear PA With 33% Peak PAE and Comparison of Stacked Common Base and Common Emitter PA in InP

• Published in: IEEE microwave and wireless components letters Vol. 31; no. 6; pp. 756 - 759
• Main Authors: Liu, Zheng, Sharma, Tushar, Sengupta, Kaushik
• Format: Journal Article
• Language: English
• Published: IEEE 01.06.2021
• Subjects: Broadband; common base (CB); Gain; Heterojunction bipolar transistors; high efficiency; III-V semiconductor materials; Impedance matching; Indium phosphide; InP; Linearity; millimeter-wave; stacked power amplifier; Topology; W-band
• DOI: 10.1109/LMWC.2021.3067233
• ISSN: 1531-1309

This work presents a high efficiency, compact 80-110-GHz InP power amplifier (PA) based on stacked common base (CB) topology and a counterpart design using conventional stacked common emitter (CE) topology. The comparison between the two exhibits that the former delivers higher power gain, superior-gain compression behavior (linearity), and higher back-off efficiency in <inline-formula> <tex-math notation="LaTeX">W </tex-math></inline-formula>-band in 250-nm InP heterojunction bipolar transistor (HBT). At 90 GHz, the stacked CB/CE PA achieves 11.8 dB/6dB gain, 33%/34% peak PAE, 16.8%/14.5% PAE at 6-dB back-off, and Psat of 18.7 dBm/19.6 dBm. Modulation test exhibits an EVM of 2.38% at 11.8-dBm average power supporting 3 Gbps 64-QAM for the stacked CB PA. The stacked CB PA with 17.9-18.9-dBm Psat across 80-110 GHz demonstrates one of the highest efficiency, broadband and linear PAs in <inline-formula> <tex-math notation="LaTeX">W </tex-math></inline-formula>-band using InP technology.