To meet the high standard requirements for broadband high-efficiency power amplifiers in modern communication technology, a 6–18 GHz high-efficiency monolithic microwave integrated circuit (MMIC) power amplifier was developed using a 0.25 μm gallium nitride high-electron mobility transistor (GaN HEMT) process. A multistage Chebyshev-filter-based matching approach is utilized to provide the requisite bandwidth while concurrently managing second-harmonic terminations for enhanced PAE. In the final power stage, a multi-cell combining architecture is employed to achieve high saturated output power. The designed GaN amplifier achieves a saturated power of above 43.5 dBm and a PAE of over 30%. The area of the proposed GaN amplifier is 4 × 3.2 mm2. This chip, with its high efficiency and compact size, is promising for high-performance wideband systems.
Liu et al. (Wed,) studied this question.