Lecturer: Marco Bressan  

Course name: Campi elettromagnetici e circuiti II
Course code: 502512
Degree course: Ingegneria Elettronica e delle Telecomunicazioni
Disciplinary field of science: ING-INF/02
L'insegnamento è caratterizzante per: Ingegneria Elettronica e delle Telecomunicazioni
University credits: CFU 9
Course website: http://microwave.unipv.it/pages/campi_circuiti_II/

Specific course objectives

Aim of the course is to supply students with base knowledge’s about electromagnetic waves and to introduce them to the methodology for their quantitative analysis. In particular, the course deals with the propagation of electromagnetic waves in free space, in dielectrics, in conductors, in cool plasmas and in guiding structures such as transmission lines and hollow waveguides. Aim of the course is also to treats the phenomena of reflection and refraction of electromagnetic waves in canonical geometries and the phenomenon of radiation from sources distributed into finite volumes. The course supplies also base knowledge’s about the main types of antennas and the parameters characterising both transmitting and receiving antennas.

Course programme

The course is of fundamental importance in the university education of engineers to work in the field of electronics and of telecommunications. It supplies the basis knowledge’s and methodologies to tackle, in following courses, the study of a number of practical interest matters in the field of radio-frequency and microwaves circuits, of optics, of antennas, of radio links, of remote sensing and of electromagnetic compatibility.

1. Fundamental concepts and laws
Force acting on a moving point charge, macroscopic electromagnetic field representation, Maxwell equations, conditions at a discontinuity surface of the medium, constitutive equations with special attention to linear, stationary and isotropic media. Charge and energy conservation. Uniform planar waves in free space.

2. Time harmonic fields
Representation of monochromatic fields, waves functions, monochromatic fields polarization. Basic equations for time harmonic fields. Electric and magnetic spectra of the matter. Mean value of energy parameters, mean power balance. Homogeneous Helmoltz equation. Fields in presence of a plane symmetry.

3. Plane waves
Plane waves and uniform plane waves. Propagation in free space, in low loss dielectrics, attenuation, propagation in a cool plasma and in good conductors, skin effect; the perfect conductor as a limiting case. Plane waves and the geometrical optics approximation.

4. Reflection and refraction of uniform plane waves
The reflection law, Snell law, Fresnel formulas, total reflection, Brewster angle. Reflection at interfaces with conducting media. Reflection and transmission with normal incidence at a planar interface between different media. Reflection at interfaces with perfectly conducting media, stationary waves. Essentials of half and quarter wavelength layers. The reflection and transmission in the geometrical optics approximation. Multi-path propagation. Lens and parabolic reflectors.

5. Guiding structures
Hertz-Debye potentials, waveguide theory, modal propagation, rectangular and circular waveguides. Electromagnetic theory of transmission lines, coaxial cables. Propagation of band-limited signals: the group velocity.

6. Radiation
Lorentz potentials and their integral representation in the case of sources distributed in finite volumes, the far field approximations and the characteristics of the field in the Fraunhofer zone. Elementary dipoles and loops, dipoles of length comparable with wavelength.

7. radiation in an half space
Boundary value problems. Uniqueness theorem, radiation in presence of a perfectly conduction plane, images rules. Radiation from apertures, rectangular aperture with uniform illumination.

8. Antennas
Characteristic parameters of transmitting antennas. Essentials on main types of antennas: dipoles, half-dipoles resonant slots, truncated waveguides, horn and parabolic reflector antennas. Array antennas, linear arrays. The reciprocity theorem, receiving antennas, radio link equation.

Course entry requirements

To profitably attend to the lectures, and pass the examination, students must have a thorough knowledge of the following mathematical and physical topics and computing instruments: complex numbers, vector algebra, differential operators on scalar and vector fields, divergence theorem, Cartesian and spherical reference systems, concept of force, energy, power, concept of field, charge, current, electric and magnetic polarization of matter, static electric and magnetic fields, Maxwell equations, units of measurement of physical quantities in the MKSA system.

Course structure and teaching

Lectures (hours/year in lecture theatre): 50
Practical class (hours/year in lecture theatre): 35
Practicals / Workshops (hours/year in lecture theatre): 0

Suggested reading materials

G. Conciauro, L. Perregrini. Fondamenti di onde elettromagnetiche. McGraw-Hill, 2003.

Testing and exams

The exam consists on a written and an oral combined tests: only students who get 15/30 in the written test are admitted to the oral one.