Single-Stage and Multiplicative Distributed Amplifiers for 200GHz+ Amplification

In this paper, we review the merit of the single stage distributed amplifier (SSDA) and consider the potential of its derivative multiplicative amplifier topologies (the cascaded and the matrix SSDA) for ultra-wideband amplification. We highlight the significant bandwidth advantage that the SSDA topology offers and the higher gain potential of multiplicative DAs compared to the conventional multi-stage DA. Furthermore, we describe how available design trade-offs may be used to offset inherent noise performance limitations of this family of distributed amplifiers. We also report a new SSDA MMIC with 7.1 dB gain at 200 GHz bandwidth and a high frequency gain tuning range of 5 dB to 12 dB, based on an Indium Phosphide DHBT process with 250 nm emitter width.