An X-Band 50W-Output/30%-PAE GaN Power Amplifier with Bandwidth/Ripple-Optimized Bandpass Impedance-Matching Networks

An X-band 50 W GaN power amplifier (PA) is presented, mainly focusing on its impedance-matching networks to realize a specified operating bandwidth of 18%. Bandpass impedance-matching networks (IMNs) with Chebyshev response are adopted in the PA, where a FET and a pre-matching transmission line can be approximately seen as a shunt parallel-resonant circuit. Mismatch-loss ripple of the Chebyshev IMN can be theoretically optimized in terms of Q-factor of the FET and a specified operational bandwidth. The designed PA has achieved an output power of 50 W and a power-added efficiency (PAE) of more than 30% in the 18% relative bandwidth.