- Docente: Vittorio Rizzoli
- Credits: 6
- SSD: ING-INF/02
- Language: Italian
- Teaching Mode: Traditional lectures
- Campus: Bologna
- Corso: Second cycle degree programme (LM) in Electronic Engineering (cod. 0934)
Learning outcomes
DEVELOPMENT OF A THOROUGH SCIENTIFIC-METHODOLOGICAL UNDERSTANDING OF RADIATING AND NON-RADIATING ELECTROMAGNETIC SYSTEMS. USE OF SUCH KNOWLEDGE IN THE ANALYSIS AND DESIGN OF DISTRIBUTED CIRCUITS AND ANTENNA SYSTEMS OF INTEREST IN MODERN ELECTRONIC APPLICATIONS.
Course contents
Transmission lines as dynamic systems that may be rigorously described by circuit equations. Multiwire data buses with homogeneous and non-homogeneous dielectric. Computation of the circuit parameters. Matching conditions and characteristic impedance. Distributed-circuit concept. Telegraphists' equations and equivalent circuit. Conditions under which inductances may be neglected. Empirical use of the equivalent circuit: analysis of R-C interconnections. Interactions with electronic devices operating in quasi-stationary conditions. Mode orthogonality and excitation of multiwire systems. Signal and power exchange among the system wires. Waveform distortion due to coupling and dispersion. Electromagnetic definition of multiport electric network. Physical and electric ports, relationships between electric ports and feeding waveguide modes. Scattering matrix and its properties. Interconnection of multiport networks, system impedance level. TEM networks (electric circuits). Electromagnetically rigorous formulation of circuit theory and discussion of its limitations. Impedance and admittance matrix of a TEM multiport network. Thévenin's and Norton's theorems. Two-port and one-port networks as special cases. Lossless impedance matching networks and their realisation by microwave integrated-circuit technology. General properties of antennas as mathematical sources. Phase center. Antenna thermal noise and equivalent noise temperature. Basic approach to radio system design. Foundations of computational electromagnetics. Method of moments. Scattering problems. Received and scattered power by an antenna. Antenna impedance and reflection coefficient. Resonant antennas. From guided-wave to free-space propagation: transition from the transmission line to the electromagnetic dipole. Closed-form and numerical analysis of dipoles. Array antennas. Linear uniform arrays. Two-dimensional planar arrays. Applications: electromagnetic screens, radar antennas, antennas for radio-base stations. Phased arrays and electronic scanning. Switched-line phase shifters. Couplings between array elements. Parasitic elements. Numerical analysis of array antennas: Yagi-Uda arrays, folded dipoles, log-periodic antennas, bow-tie (biconical) antennas. Aperture antennas. Radiation from an aperture under general conditions. Uniformly polarized TEM apertures. Aperture efficiency. Huygens' source. Huygens-Fresnel's principle and electromagnetic diffraction. Uniformly illuminated circular TEM aperture. Applications: antennas for tropospherical radio links, radiotelescopes, direc-broadcasting satellite receivers. Planar integrated (microstrip) antennas. Rectangular patch antenna: approximate analysis by an intuitive model based on radiating apertures. Numerical analysis of arbitrarily shaped antennas by the method of moments. Applications: electronically scanned microstrip antenna arrays, internal integrated antennas for mobile transceivers, integrated broadband antennas, spiral antennas.
Readings/Bibliography
TEXTBOOK ON ANTENNAS: V. RIZZOLI AND D. MASOTTI, 'LEZIONI DI SISTEMI D'ANTENNA' (VOL. 1 AND 2), ESCULAPIO-PROGETTO LEONARDO, 2010/2011.
REFERENCE TEXTBOOKS: L. STUTZMAN AND G. A. THIELE, 'ANTENNA THEORY AND DESIGN', JOHN WILEY & SONS, 1998. V. RIZZOLI AND A. LIPPARINI, 'PROPAGAZIONE ELETTROMAGNETICA GUIDATA' (PARTS 1 AND 2), ESCULAPIO-PROGETTO LEONARDO, 1998/2002.
Teaching methods
THE CLASSROOM LECTURES ARE INITIALLY DEVOTED TO THE DISCUSSION OF THE GENERAL ASPECTS AND OF THE ANALYSIS TECHNIQUES FOR DISTRIBUTED CIRCUITS AND ANTENNAS, INCLUDING THE FOUNDATIONS OF COMPUTATIONAL ELECTROMAGNETICS. SUCH KNOWLEDGE IS SUBSEQUENTLY APPLIED TO THE IN-DEPTH TREATMENT OF DISTRIBUTED COMPONENTS AND ANTENNA SYSTEMS OF MAJOR INTEREST FOR ELECTRONIC APPLICATIONS. THE TRAINING HOURS ARE DEVOTED TO THE USE OF SIMULATION PROGRAMS FOR THE NUMERICAL ANALYSIS OF ELECTROMAGNETIC SYSTEMS.
Assessment methods
ORAL DISCUSSION AIMED AT ESTABLISHING THE STUDENT'S UNDERSTANDING OF THE ANALYSIS AND DESIGN TECHNIQUES AND OF THE SPECIFIC PROPERTIES OF RADIATING AND NON-RADIATING ELECTROMAGNETIC SYSTEMS. SOLUTION OF SIMPLE APPLICATION PROBLEMS.
Teaching tools
LECTURE NOTES ARE AVAILABLE WHERE MOST OF THE TOPICS DEVELOPED IN THE COURSE ARE DEALT WITH IN DETAIL. THE CLASSROOM TEACHING IS SUPPORTED BY THE PROJECTION OF SLIDES CONTAINING MOST OF THE MATHEMATICAL DETAILS, IN ORDER TO PARTLY WAIVE THE NEED FOR THE STUDENTS TO TAKE NOTES DURING THE LECTURES, ESPECIALLY FOR MATHEMATICS. COPIES OF ALL SUCH SLIDES ARE AVAILABLE THROUGH THE INTERNET (IN THE COURSE HOME PAGE, FOLLOW THE LINK "MATERIAL").
Office hours
See the website of Vittorio Rizzoli