Dynamic load modulated low-voltage GaN PA using novel low-loss GaN varactors

This paper gives a first presentation of a dynamic load modulated (DLM) power amplifier (PA) employing novel AlGaN/GaN varactors. With an AlGaN/GaN HEMT this enables the highest operating frequency ever presented for avaractor-based GaN DLM PA. Despite the low drain-source voltage of 10V, making the PA suitable for mobile applications, it shows a high drain efficiency of 61% at a maximum output power of 24dBm. At 6dB output power back-off the PA still reaches 45% efficiency. The achieved results demonstrate the promising potential of AlGaN/GaN varactors, and show the usability of AlGaN/GaN HEMT at low voltages.