Creating and sharing knowledge for telecommunications

João Gomes wins a $6,000 MTT-S fellowship

on 28-07-2020

... João is pursuing his PhD in Electrical Engineering, hosted by IT in Aveiro, under the supervision of José Pedro, Luís Nunes (both from IT/UA) and Nikolai Sobolev (UA). (see more)

João Gomes, a PhD student from the University of Aveiro (UA) and a research assistant with the IT in Aveiro has won a Graduate Student Fellowship in the amount of $6,000 sponsored by the largest scientific society in the microwave area, the IEEE Microwave Theory and Techniques Society - MTT-S, for his work “Nonlinear Modeling of GaN HEMTs for RF and Microwave Applications”.

A wireless communication system uses a power amplifier (PA) to increase the signal amplitude before transmitting it through the antenna. These power amplifiers are the components that most consume power in a base-station, which led the telecom industry and scientific community to invest into more energy-efficient PA designs. Furthermore, faced with the new 5G requirements, the complexity of PA systems for wireless communications has been quickly escalating with the increase in signal bandwidth and the required efficiency and linearity. In addition, the adoption of higher frequencies and monolithic implementations has ascribed an essential role to nonlinear models for PA design.

Unfortunately, the state-of-the-art models of RF power transistors are not sufficiently accurate to design a PA based only on computer-aided design simulations, especially for technologies such as high electron mobility transistors based on Gallium Nitride (GaN-HEMTs) that are quickly becoming a promising next-generation power semiconductor. The biggest challenge to obtain accurate nonlinear models is how to mimic the low-frequency dispersion behavior that are normally observed in these transistors. This insufficiency of the representative and predictive capabilities of modern models is notably revealed by the nonlinear capacitance models’ internal inconsistency between the charge and energy conservation principles.

The objective of this project was thus, to discover the fundamental sources of these inconsistencies and then develop new equivalent circuit compact models of GaN HEMTs that can produce better estimations of real high-frequency measured data while maintaining high computational efficiency.

In the 2020 MTT-S Graduate Student Fellowship Awards, 47 applications from 14 countries were received in the general category, and 10 applications from four nations were received in the medical area. Twelve graduate fellowships were awarded for 2020 in the general category and two in the medical applications domain.

Biometrics and accident detection

on 23-07-2020

... The BIOID project resorts to services based on the detection of security incidents as well as awareness of healthy habits. (see more)

The European Innovation Partnership on Smart Cities and Communities (EIP-SCC) highlights in the measure “Infrastructures and integrated processes in energy, ICT and transport” the role of ICTs in the governance of territories, namely in the sense of becoming the critical link between infrastructures and information in real time, which allows these territories to change from reactive to predictive operations.

Attending these concerns, IT (under the coordination of Hugo Proença) and TOMI WORLD are working on project BIOID, that aims to respond to health prevention needs through the safety and well-being of citizens resorting to services based on the detection of security incidents as well as awareness of healthy habits. As part of the incident detection, the system triggers a notification in the respective authorities. Awareness will be based on the promotion of healthy behaviors by the interaction of the citizen with gamified content in the interactive TOMI equipment.

“TOMI is an interactive device that provides a set of information about the city in which it is located (e.g., events, points of interest, public services, among others). These devices are located in strategic places in the cities, in order to make them accessible to the largest number of citizens. This makes them an ideal vehicle to act as security agents in the city”, explains João Neves, Computer Vision Engineer at TOMI WORLD.

The BIODI project aims to develop applications based on Computer Vision techniques that allow a) to automatically detect security incidents on the public road, (e.g. assaults, assaults or abandoned objects) and rescue incidents (eg, fainting, or fallen); b) identify weak biometric traits (age, gender, height, but also characterization of clothing and gait style) that allow research by subjects in a observation list.

Photo: Computer vision is an interdisciplinary scientific field that deals with how computers can gain high-level understanding from digital images or videos. Credits: