A 4.4-6.4-GHz Compact SiGe Power Amplifier with 30.5-dBm Psat and 34.8% PAE Based on Triple-Tank Power Combiner

Abstract

This letter presents a broadband compact watt-level high-efficiency power amplifier (PA) in 0.35-μm SiGe BiCMOS process. A four-way triple-tank-based power combiner is introduced and theoretically analyzed in detail with the consideration of the undesired inductor in the third tank. The coupling coefficient and the uncoupling resonant frequencies of the tanks can be adjusted to compensate for the deterioration caused by the undesired inductor, achieving broadband and low-loss matching. The proposed PA operates over 4.4-6.4 GHz and exhibits a peak gain of 35.2 dB, a maximum saturated output power (Psat) of 30.5 dBm, and a peak power added efficiency (PAE) of 34.8% at 5.4 GHz.