A 10-W High-Power Amplifier Using Input Nonlinearity for K-Band Satcom Applications

This letter presents a
${K}$
-band 0.1-
$\mu \text{m}$
GaN on Si 10-W high-power amplifier (HPA) for the downlink of the satellite
communication
system. The proposed HPA uses the driver-stage transistor to generate a half-sinusoidal waveform that is delivered to the power-stage transistor. The half-sinusoidal waveform combines the input nonlinearity of the power-stage transistor to simultaneously improve the efficiency and expand the design space of the input harmonic impedance. A simple and compact interstage matching network (ISMN) design is used to match the harmonic impedance of both driver and power-stage transistors to create the corresponding waveforms. The proposed HPA has a small size of 3.5 mm
$\times3.2$
mm and operates in the frequency range of 17–20.5 GHz achieving a 22-dB gain, an average output power (
${P}_{\mathbf {out}}$
) of 42 dBm, and 41% power-added efficiency (PAE) in the pulsed measurement. Moreover, the proposed HPA maintains a PAE of more than 33% and output power of 40.4 dBm in continuous wave (CW) measurement.