Millimeter-wave design considerations for power amplifiers in an SiGe process technology

This paper describes a number of significant modeling considerations for SiGe heterojunction bipolar transistor power amplifiers operating at millimeter-wave frequencies. Small- and large-signal model-to-hardware correlation is presented for single transistor amplifiers, as well as for a combined dual-stage amplifier up to 65 GHz. The relevant parasitic effects are described along with the proposed modeling approach for each of them. The limits of the standard Vertical Bipolar Inter-Company device model at high-injection and their effect on the prediction of the achievable large-signal compression and power-added efficiency are also discussed.