Design of an Ultrawideband MMIC Power Amplifier Based on Mixed Operation Mode

This letter presents a novel ultrabroadband, high-efficiency MMIC power amplifier (PA). To reduce performance degradation caused by nonconvergent impedance in high-frequency ultrawideband designs, the extended continuous Class-GF mode (ECCGF) and Class-GF-1 (ECCGF-1) mode is integrated. Then the impedance in the high-frequency range is aligned with the ECCGF-1 mode, while lower frequency impedance corresponds to the ECCGF mode. A three-section L-C matching network is used to satisfy these requirements, with parameter derivations provided. In addition, an L-R series structure is implemented to adjust the input harmonic component, and the impact of L on both the harmonic component and PAE is analyzed. The proposed high-efficiency wideband MMIC PA, fabricated using a 0.25-<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula>m GaN HEMT process, achieves a saturated output power of 44.2–45.8 dBm over 6–18 GHz, with a gain of 18.1–21.1 dB and a PAE of 24.9%–33.6%. The figure of merit (FOM) reaches 1.19, indicating a significant improvement compared with existing works.