What is HPA (High Power Amplifier)?

The high-power amplifier (HPA) gives the RF power for a payload downlink. The HPA subsystem has capacities that Channel preamplification for the HPA, with the adaptability to make the downlink power autonomous of the uplink power over a wide range of uplink power. A high power amplifier is a non-linear device which amplifies a small signal to a significant level. The HPA composed of 12 HBTs AsGa/GaInP is indistinguishable to the transistor.