Analysis and Design of a SiGe BiCMOS PA for 6G FR3 Band With 29-dBm PSAT and 40.1% PAE

This work presents a watt-level two-stage differential power amplifier (PA) implemented in a 130-nm SiGe BiCMOS technology. The PA leverages a stacked topology to achieve high power over a wide bandwidth while employing only low-voltage high-speed (HS) bipolar devices and using a 3.3-V supply. The measured small-signal gain is 34.2 dB, with a 3-dB bandwidth ranging from 4 to 11 GHz, covering a large portion of the sixth generation (6G) new radio (NR) FR3 spectrum. The PA is capable of delivering a measured peak saturated output power of 29 dBm without the need of power combining, leading to a compact area of 1.35 mm2 , including the pads. A peak power-added efficiency (PAE, PAEPEAK) larger than 40% is measured at 5 GHz. The PA is tested with a 5G NR-FR1 modulation, achieving 6.4% error vector magnitude (EVM) and -33-dBc adjacent channel leakage ratio (ACLR) with 15.6% of average PAE (PAEAVG) at 21.5 dBm of average output power (PAVG). When tested with the 100-MHz 256 QAM signal for 5G, the PA is compliant with the 5G NR-FR1 standard up to 20 dBm of PAVG.