A 10-W 7-GHz GaN-on-Si Doherty Power Amplifier with Hybrid MMIC-Module Integration for 6G Base-Station Applications

This paper presents a 7-GHz GaN-on-Si HEMT Doherty power amplifier (DPA) with a fully integrated on-chip Doherty combiner. The hybrid MMIC-module architecture ensures precise Doherty operation with enhanced bandwidth, while maintaining the flexibility of board-level matching networks. The DPA MMIC occupies a compact core area of 1.17 × 2.25 mm². The measured DPA evaluation board (EVB) achieves a peak gain of 8 dB and a saturated power (Psat) of 41.3 dBm at 7.4 GHz. For the 64-QAM 100-MHz OFDM signals, the DPA provides an average output power (Pavg) of 32.7–33.8 dBm, resulting in a drain efficiency (DE) ranges of 39–43.9% at Pavg, while an adjacent channel leakage ratio (ACLR) satisfies below -28.5 dBc at Pavg across carrier frequencies from 7 to 8 GHz. To the best of the authors’ knowledge, this study represents the first implementation of a partially integrated MMIC Doherty architecture using GaN-on-Si process at 7 GHz.