A Simple Design Method for Harmonic-Tuned GaN MMIC Power Amplifier Using Real-to-Real LPF Matching Network

This letter presents a simple and novel design method for harmonic-tuned (HT) GaN monolithic microwave integrated circuit (MMIC) power amplifier (PA) using low-pass filtering (LPF) impedance matching network (MN). With this method, the optimal fundamental load impedance matching and harmonics tuning can be achieved by using a simple real-to-real LPF MN, while the bias line of MMIC PA is skillfully incorporated into the MN. Based on it, the design procedure of an efficient MMIC PA is simpler and straightforward. As an example, a HT MMIC PA is designed and fabricated in 0.25 ~\mu \mathrm {m} GaN-on-Si technology. The experimental results show that the implemented HT PA delivers a maximum power-added efficiency (PAE) of 42%-50.8% and the saturated output power of 39.2-40.8 dBm in the range of 2.6-3.6 GHz.