A Monolithic X-Band 32 dBm GaAs HBT Power Amplifier with Efficient Operation Over a Wide Range of Power Supply Voltages

Power amplifiers at the fr3 frequency band (7–20 GHz) are attracting attention for possible use in 6G wireless systems, and the comparison between different transistor technologies that could be applied is an emerging research focus. Relative to 5G mm-wave power amplifiers, higher output power (up to 30–35 dBm), high efficiency and high linearity are important requirements for 6G. This paper focuses on design considerations for GaAs HBT technology at fr3, which is higher in frequency than customary GaAs HBT applications. A single-stage, single-ended amplifier is reported which achieves Psat above 32 dBm and PAE above 37% at 10 GHz. Peak PAE remains above 30% and gain variation is small as the power supply voltage is changed over the range 1 V to 6 V, characteristics that are highly favorable for envelope tracking systems.