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

Abstract

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.

InP DHBT Single-Stage and Multiplicative Distributed Amplifiers for Ultra- Wideband Amplification

“…For over eighty years, the concept of distributed amplification, which allows the absorption of the bandwidthlimiting intrinsic capacitances of active devices into artificial transmission lines (ATLs) [5]- [7], has been employed in the design of amplifiers with bandwidth performance approaching the terahertz frequency bands (i.e. 0.3 -3 THz) [1], [8], [9]. The conventional distributed amplifier (DA), as shown in Fig.…”

“…The multiplicative gain mechanism of these topologies make them particularly attractive, as they make it possible to achieve significantly higher gain-bandwidth product performance, with fewer gain cells than the conventional, additive DA. Both derivative topologies of the SSDA have been described as multiplicative DAs in [1] due to their gain mechanism.…”