A monolithic microwave-integrated circuit 2-stage power amplifier (PA) realized in indium phosphide double heterojunction bipolar transistor technology is presented in this article. The 2- and 3-stacked transistors are used in the driver and power stages, respectively. As a mean to increase the output power capabilities, 2- and 4-way corporate power combiners are implemented in coplanar waveguide technology. The fabricated PA exhibits a small-signal gain of 13.6 dB at 77 GHz and a 3-dB bandwidth ranging from 74 to 86 GHz. At 78 GHz, the saturated output power is >19.6 dBm.
- Double heterojunction bipolar transistor
- Indium phosphide
- P½ower amplifier
- Power combining
- Stacked transistor