Compact highly integrated X-band power amplifier using commercially available discrete GaN FETs

This paper describes the design and characterization of a highly integrated X-band power amplifier that utilizes commercially available discrete GaN transistors. The compact design integrates all of the RF matching and bias circuitry on to er=36 circuit boards, one for the input and one for the output. This includes the DC blocks, RF bypasses and RF chokes. Dimensions for the complete single stage power amplifier are 9.8 × 8.6 mm2. Measured results for the GaN power amplifier under pulsed bias conditions demonstrate up to 66W output power with associated gain and power added efficiency of 8.3dB and 45% respectively.