Microwave and Millimeter Wave Integrated Circuit (MMIC) design, modeling and characterization
MMIC modeling and design has been in the core research activities of the group during the last 30 years. In the area of component modeling, the activities have ranged from active device modeling based on physical transport models (applied to GaAs MESFET and HEMTs, GaN HEMTs, GaAs HBTs, SiC MESFETs), to thermal and coupled electro-thermal modeling of devices and ICs (through analytical, semi-analytical and numerical techniques) to the electromagnetic modeling of integrated transmission lines (with particular attention to coplanar waveguides, and exploiting both analytical tools, like conformal mapping, and numerical techniques accounting also for complex, e.g. lossy semiconductor, substrates).
Circuit design has mainly concerned power microwave amplifiers on GaAs and GaN technologies, but also the modeling and design of RF and baseband predistortion stages and of other RF blocks (mixers, oscillators, LNA). Circuit design was based on circuit-level transistor models (in this area self-consistent coupled electro-thermal models were developed with application to GaN and GaAs technologies) and on behavioural modeling of power amplifiers, but also on a strong experimental activity on the power characterization of microwave devices, with particular attention to the development of active load-pull systems up to 40 GHz.
Recently, part of the research activities of the group have been focused toward multistage high power (>100 W), high frequency amplifier, using conventional approaches and innovative strategies (e.g. the Doherty scheme) both concerning design and characterization issues.
The research was carried out within a large number of projects (the European COSMIC and MANPOWER projects and the TARGET and NEWCOM european NOEs; the KORRIGAN EUROFINDER project; a number of Italian PRIN projects, e.g. the GaNFET and FPFET projects in 2003-2008 coordinated by the research group); several ASI projects (PATRAS, DECO2G), a FIRB project in progress and a number of industrial cooperation (with SIAE, Infineon, ITERRA, ST Microelectronics, Philips-NXP). Cooperation are on going with Ericsson, Chalmers Gigacenter Foundry, Triquint.