2-6 GHz GaN MMIC Power Amplifiers for Electronic Warfare Applications

This paper presents two MMIC broadband high power amplifiers of 4 mm of periphery at the output stage in the frequency band 2-6 GHz. The amplifiers are based on Al-GaN/GaN high electron mobility transistor (HEMT) technology on SiC substrate. They have been fabricated in two different european foundries: SELEX Sistemi Integrati and QINETIQ. SELEX has a gate process technology of 0.5 mum, and devices of 10times100 mum periphery in microstrip technology and QINETIQ has a gate-length of 0.25 mum, and devices of 8times125 mum in coplanar technology. The coplanar amplifier from QINETIQ has demonstrated an output power of 8 W in continuous wave at V
_ds
=20 V which confirm model predictions. On the other hand, SELEX microstrip amplifier has a saturation power of 10 W CW at V
_ds
=25 V and 4 GHz. This amplifier measured on-wafer in pulsed conditions exhibits a maximum power of 17 W at V
_ds
=30 V.