Electronics for Telecommunications
Research Laboratory

Several hybrid and monolithic microwave integrated circuits have been designed in collaboration with various industrial, research, and academic partners. These include X-band MMIC Doppler sensors, highly linear cold-FET mixers, wideband PHEMT LNAs, DROs, push-push VCOs, and L- to V-band GaAs and GaN power amplifiers, among others.

In this context, the main contribution of the ETLab research group focused on supporting designers through accurate technology characterization and advanced transistor modeling, enabling state-of-the-art circuit performance.

A novel design methodology, based on the Low-Frequency Load-Pull setup developed by the group, was also introduced. This approach utilizes the waveforms measured at the transistor's current-generator plane as the starting point. Subsequently, by employing a model of the device's nonlinear capacitances and parasitic elements, their contributions can be “embedded” to determine the appropriate terminations at the actual device terminals. This technique is known as “nonlinear embedding”.

Compared to conventional circuit design approaches, the nonlinear embedding methodology eliminates the need for time-consuming load/source-pull measurements or laborious simulations to identify the device's optimal operating condition. This is because the optimal condition, uniquely defined by power amplifier design theory for each class of operation, is easily determined at the transistor’s current-generator plane and serves as the starting point for the nonlinear embedding approach.

Examples of HMIC and MMIC circuits designed using the nonlinear embedding technique