A 2GHz GaN Class-J power amplifier for base station applications

The design and implementation of a high efficiency Class-J power amplifier (PA) for base station applications is reported. A commercially available 10 W GaN HEMT device was used, for which a large-signal model and an extrinsic parasitic model were available. Following Class-J theory, the needed harmonic terminations at the output of the transistor were defined and realised. Experimental results show good agreement with simulations verifying the class of operation. Efficiency above 70% is demonstrated with an output power of 39.7 dBm at an input drive of 29 dBm. High efficiency is sustained over a bandwidth of 140 MHz.