A variable output power, high efficiency, power amplifier for the 2.45 GHz ISM band

This paper, presents the design and evaluation of a high efficiency, 30 W, two-stage, power amplifier for the 2.45 GHz ISM band. The designed amplifier targets an industrial application where precise control over the output power with good efficiency is necessary. A saturated output power of 44.7 dBm (30 Watts) was reached at a maximum drain efficiency of 67.8%. A full 5 dB control of the output power was achieved by varying the gate bias of the driver stage. A minimum power added efficiency of 39.4% was reached over the full controllable output power range at the design frequency. The saturated output power over a 150 MHz bandwidth around the design frequency was more than 44 dBm with a power added efficiency of more than 60%.