12:00-12:30

Opening: Prof. Carmen Garcia-Mateo, Coordinator of Doc_TIC PhD Program

Prof. Manuel García-Sáncez, Secretary of the Academic Board

12:30-13:30

Lecture by Dr. Efren Fernandez-Grande 

Chairperson: Prof. Manuel Sobreira Seoane

Dr. Efren Fernandez-Grande 

Assistant Professor

Acoustic Technology group

Technical University of Denmark

Acoustic imaging methods are useful in order to localize sound sources, examine how these sources generate sound, analyze complex sound fields (e.g. in rooms, vehicles, outdoors ...), and characterize the acoustic properties of materials. These methods typically rely on measurements with an array of microphones in order to characterize the spatio-temporal properties of the sound field under study. In this talk we will discuss conventional acoustic imaging methods and present novel imaging techniques based on Compressive Sensing (CS).

Compressive Sensing is a powerful signal processing framework that promotes sparse representations of a signal: this implies that the data measured with the array is represented as the superposition of a minimal number of waves. This representation is valuable, because we essentially recover the dominant sources or components that create the observed wave field; This constitutes an interesting alternative to the classical least-squares approaches. We will discuss applications where these imaging techniques are useful such as sound source localization, sound absorption estimation, and acoustic holography.

Efren Fernandez-Grande obtained a BSc degree in Telecommunication Engineering from the Polythecnic University of Madrid (UPM) in 2006, a MSc degree in Engineering Acoustics (2008) from the Technical University of Denmark (DTU), and a PhD from the Technical University of Denmark (2012), under the supervision of Finn Jacobsen (Dissertation: "Near-field acoustic holography with sound pressure and particle velocity transducers").

In 2012 he received an individual postdoctoral grant from the Danish Council for Independent Research (DFF) and since 2014, he is Assistant Professor at the Acoustic Technology group at DTU, Department of Electrical Engineering. He has been a visiting researcher at the Laboratoire Vibrations Acoustique (LVA) at the National Institute of Applied Science (INSA) in Lyon in 2012, and at the Signal Processing group of the Scripps Institution of Oceanography, Univ. of California in San Diego in 2015.

Efren F. Grande's research lies within the area of sound field analysis and advanced measurement techniques. Specific research interests include near-field acoustic holography (NAH), beamforming, compressive sensing, sound intensity measurements, signal processing and inverse problems in acoustics. Efren teaches several courses including Fundamentals of Acoustics and Noise Control, Advanced Acoustics and Music Technology and Perception at DTU. He has contributed to 33 technical papers and participated in industrial projects with Brüel & Kjær, Bang & Olufsen, Vestas Pipecon among others, and he is currently involved in the design of the anechoic Danish National Wind Tunnel, where he is responsible for the design of the array measurement system and anechoic test section.