Design and realization of a millimeter-wave Si/SiGe HBT frequency multiplier

In this paper, the design of an active millimeter-wave frequency doubler using an Si/SiGe heterojunction bipolar transistor (HBT) as the active device is studied. Simulations are made using a developed physics-based large-signal model for Si/SiGe HBT's, which includes thermal dependence. Despite the high-output operating frequency of the fabricated doubler being close to f/sub max/ 67 GHz for the Si/SiGe HBT, the conversion efficiency in a not...