Lecture

Doppler Effect and Radar Applications

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In course

EE-445: Microwaves, the basics of wireless communications

This course is an introduction to microwaves and microwave passive circuits. A special attention is given to the introduction of the notion of distributed circuits and to the scattering matrix ...

Description

This lecture covers the Doppler effect and its application in radar systems, explaining how the frequency of a wave changes when the source or receiver is in motion. It also discusses examples of Doppler radar calculations, such as determining the frequency shift for moving sources. Furthermore, it delves into the principles of radar systems, including the concept of attenuation in free space and the Friis' formula for calculating received power. The lecture concludes with a focus on diffraction phenomena, exploring how obstacles affect wave propagation and introducing the concept of Fresnel ellipsoids. Finally, it touches on satellite communication, explaining Kepler's laws and providing insights into geostationary satellites.

Instructor

Anja Skrivervik

Anja Skrivervik obtained her electrical engineering degree from Ecole Polytechnique Fédérale de Lausanne in 1986, and her PhD from the same institution in 1992, for which she received the Latsis award. After a stay at the University of Rennes as an invited Research Fellow and two years in the industry, she returned part time to EPFL as an Assistant Professor in 1996, and is now a Professeur Titulaire at this institution, where she is the head of the Microwave and Antenna Group. Her research activities include electrically small antennas, antennas in biological media, periodic structures, reflect- and tranmitarrays, and numerical techniques for electromagnetics. She is author or co-author of more than 200 peer reviewed scientific publications. Her teaching activities include courses on microwaves and antennas, and she has course at Bachelor, Master and PhD levels. She was director of the EE section form 1996-2000, and is currently the director of the EE doctoral school at EPFL. She is very active in European collaboration and European projects. She was the chairperson of the Swiss URSI until 2012, is a Board member of the European School on Antennas and is frequently requested to review research programs and centers in Europe. She is a member of the board of directors of the European Association on Antennas and Propagation (EurAAP) since 2017.

Official source

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Wave

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Kepler problem

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Kepler's equation

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