Design and modeling of an ultra-wideband low-noise distributed amplifier in InP DHBT technology
Int. J. Microwave Wireless Technolog., vol. 11, no. 7, pp. 635-644 (2019).
Copyright © Cambridge University Press and the European Microwave Association 2019. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the Cambridge University Press and the European Microwave Association.
This paper reports on an ultra-wideband low-noise distributed amplifier (LNDA) in a transferred-substrate InP double heterojunction bipolar transistor (DHBT) technology which exhibits a uniform low-noise characteristic over a large frequency range. To obtain very high bandwidth, a distributed architecture has been chosen with cascode unit gain cells. Each unit cell consists of two cascode-connected transistors with 500 nm emitter length and ft/fmax of ∼360/492 GHz, respectively. Due to optimum line-impedance matching, low common-base transistor capacitance, and low collector-current operation, the circuit exhibits a low-noise figure (NF) over a broad frequency range. A 3-dB bandwidth from 40 to 185 GHz is measured, with an NF of 8 dB within the frequency range between 75 and 105 GHz. Moreover, this circuit demonstrates the widest 3-dB bandwidth operation among all reported single-stage amplifiers with a cascode configuration. Additionally, this work has proposed that the noise sources of the InP DHBTs are largely uncorrelated. As a result, a reliable prediction can be done for the NF of ultra-wideband circuits beyond the frequency range of the measurement equipment.
1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik (FBH), Berlin, Germany
2 Brandenburg University of Technology Cottbus-Senftenberg (BTU), Cottbus, Germany
3 Technical University of Denmark (DTU), Kgs. Lyngby, Denmark
4 Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany
InP DHBT; distributed amplifier; low noise amplifier; travelling wave; ultra-wideband amplifier; cascode.