Packaged AlGaN/GaN HEMT power bars with 900 W output power and high PAE at L-band

This paper describes the performance of packaged power bars that are realized in a 0.5 μm gate length AlGaN/GaN HEMT technology on SiC substrates, assembled together with pre-matching circuitry in a ceramic package and designed for operation at 1030 MHz (L-Band). Two different package assemblies are compared: The first one uses a single power bar, and the second one uses four parallel power bars. Fundamental passive load-pull at 50 V DC drain supply voltage under pulsed excitation with 10% duty cycle shows output power levels of 260 W and 900 W at 3 dB compression with an associated PAE of 62% and 66%, respectively, for the first and second assembly. The first assembly is further characterized using an active harmonic load-pull system, which demonstrates an increased output power of about 325 W at 69% PAE when tuned for maximum power, or peak PAE values exceeding 75% at an output power of 260 W when tuned for maximum efficiency.