ING-INF/02 (ELECTROMAGNETIC FIELDS)
DEPARTMENT OF ELECTRICAL,COMPUTER AND BIOMEDICAL ENGINEERING
2nd semester (08/03/2021 - 14/06/2021)
84 lesson hours
Basic concepts in electromagnetics, telecommunications and mathematics. In particular knowledge of principles of electromagnetic fields, antennas, guided wave propagation in waveguides and transmission lines.
The course aims to address the theoretical aspects and applications of microwave engineering. In particular, at the end of the course the student should have acquired the theoretical and practical knowledge about microwave circuits and microwave junctions; must understand the principle of operation and design criteria of the most important passive components (attenuators, phase shifters, directional couplers, power dividers, circulators, isolators, filters, etc..). He should also be able to use dedicated matrix representations in the analysis of more complex passive circuits realized in microstrips and/or waveguides, and to design simple active circuits (e.g. amplifiers, oscillators, mixers). He should learn to use actual design and optimization tools based on CAD packages, being aware of their limitations, and critically discussing their results.
The first part of course is dedicated to theoretical considerations about guided propagation in transmission lines and waveguides, circuit representation of passive microwave junctions and resonant cavities.
The second part consists in an overview of passive microwave components, considering their principle of operation and design criteria, followed by an examination of the main issues in the design of active, nonlinear circuits.
More specifically, the course program is structured as follows:
- Mode representation of e.m. fields in waveguides and transmission lines; modal vectors and definition of equivalent voltages and currents.
Spectral representation of e.m. field in closed regions: solenoidal and irrotational eigensolutions for a closed region (ideal resonant cavity); free oscillations in a real cavity; forced oscillation in a real cavity.
- Theory of microwave junctions: Theoretical basis for matrix representation of a linear, passive microwave junction; impedance-, admittance- and scattering-matrix representation; general properties of matrices according to physical characteristics of the junction; equivalent circuits, Foster representation.
- Principle of operation and design criteria of microwave components: waveguide and microstrip attenuators and phase-shifters, impedance matching circuits, isolators and circulators, power dividers and combiners, directional couplers, microwave filters.
- Design of active and/or nonlinear circuits: study of small signal solid-state amplifiers(stability conditions, Rollet parameter, broadband amplifiers, gain equalization methods); power amplifiers (nonlinear analysis in time domain, harmonic balance methods, characteristic parameters of power amplifiers); balanced mixers and image rejection mixers; negative impedance/admittance oscillators.
- Computer aided design techniques: full-wave e.m. solvers and CAD packages based on equivalent circuits derived from electromagnetic analysis.
Lectures (hours/year): 50
Practical class (hours/year): 10
Practicals / Workshops (hours/year): 26
Reccomended or required readings
Robert E. Collin. Foundation for Microwave Engineering. McGraw–Hill, 1994.
Oral examination, possibly including the discussion of a simple project.
Sustainable development goals - Agenda 2030