Design of a 17-21 GHz Power Amplifier Based on an Extended Resistive Continuous Mode

In this paper, an efficiency improvement method in multistage power amplifier (PA) is proposed. Combined with the power stage transistor operate in continuous class-F and the driver stage transistor operate in continuous class-F-
¹
, the power-added efficiency (PAE) of multistage PA can be further improved. Meanwhile, a large power push ratio is adopted to determine the size of transistors at each stage and a voltage divider circuit is used to maintain the same bias. The proposed method was verified by implementing an MMIC PA utilizing a 0.1
$\mu \text{mGaAs}$
pHEMT process. The PA is used for the 17–21 GHz satellite communication system with a saturated output power of 1 W and an average PAE higher than 44% while having a small signal gain of 23 dB.