Unit
- Course
- Electronic engineering for the internet-of-things
- Study-unit Code
- A004785
- Curriculum
- Consumer and aerospace iot
- Teacher
- Cristiano Tomassoni
- Teachers
-
- Cristiano Tomassoni
- Hours
- 72 ore - Cristiano Tomassoni
- CFU
- 9
- Course Regulation
- Coorte 2024
- Offered
- 2025/26
- Learning activities
- Caratterizzante
- Area
- Ingegneria elettronica
- Academic discipline
- ING-INF/02
- Type of study-unit
- Opzionale (Optional)
- Type of learning activities
- Attività formativa monodisciplinare
- Language of instruction
- Italian
- Contents
- In this course some basic method for the design of the most common microwave components and systems are introduced, as impedance matching, filters, radars etc.
- Reference texts
R. Sorrentino, G. Bianchi, Ingegneria delle microonde e radiofrequenze, McGrawHill.
K.Chang, RF and Microwave Wireless Systems, J.Wiley & Sons, 2000.
R.Collin, “Foundations for Microwave Engineering”, McGraw-Hill, 1992.
D.M Pozar, “Microwave and RF Design of Wireless Systems”, J.Wiley & Sons, 2001.- Educational objectives
- The aim of the course is to provide the students with theoretical and practical knowledge for the design of microwave circuits and systems. The objective is to allow the student to use the theory to obtain a draft design that is then refined by using Computer Aided Design (CAD) software.
- Prerequisites
Knowledge of lamped circuits. Knowledge of the fundamentals of electromagnetics.- Teaching methods
Classroom-taught of theory. Exercise for the design of microwave components. Design through CAD Electromagnetic software- Other information
N/A- Learning verification modality
Oral Exam.
Report describing the design of a microwave component and its manufacturing by 3D printing.- Extended program
Course Outline. Introduction to the course. Review of microwave and RF transmission lines: coaxial, rectangular, and circular waveguides. Printed circuits.
IMPEDANCE MATCHING:
• Introduction to impedance adapters. Quarter-wavelength adapter. Variation of reflection coefficient with frequency in quarter-wavelength adapters. CAD simulation of a quarter-wavelength adapter.
• Calculation of the quarter-wave transformer bandwidth. Exercises on quarter-wave transformers. Theory of small reflections.
• Multisection transformers. Binomial transformer. Matlab exercise: writing a program for calculating the quarter-wavelength transformer in a rectangular waveguide.
• Logarithmic approximation of the binomial transformer. Binomial transformer design exercise.
• Chebyshev polynomials. Chebyshev transformer. Logarithmic approximation for the Chebyshev transformer. Exercises for the design of Chebyshev transformers. Use of tables for impedance transformer design. Writing a program for calculating the parameters of an impedance transformer for rectangular waveguides.
MICROWAVE FILTERS:
• General definitions: Power Loss ratio, Insertion Loss, Return Loss. Low-pass filter prototype. Butterworth, Chebyshev, and Cauer responses and their comparison.
• Ladder low-pass filter prototypes. Denormalization of filters in frequency and reference impedance. Example of calculating the Chebyshev low-pass response for a 2nd-order ladder prototype filter.
• Low-pass to high-pass, low-pass to band-pass, low-pass to band-stop transformations. Richards' periodic transformation.
• Review of the ABCD matrix.
• Introduction to the impedance inverter.
• Characterization of impedance inverters using ABCD matrix, Z matrix, Y matrix, and scattering matrix. Admittance inverters and their relationship with impedance inverters. Realization of inverters using lumped elements, lambda/4 transmission lines, and mixed networks.
• Transformations from series to parallel resonators (and vice versa) using impedance/admittance inverters. Equivalent circuit for resonant cavity filters: transformation of the band-pass filter with series and parallel resonators to a filter with impedance inverters and only series resonant resonators all at the same frequency.
• Equivalence between transmission line resonators and series or parallel lumped constant resonators. Definition of Slope parameter. Calculation of slope parameters for series and parallel lumped constant circuits. Slope parameter for a half-wavelength line closed on a short circuit and open circuit. Equivalent circuit of filters composed of inverters and half-wavelength lines.
• Exercises on the design of waveguide filters and microstrip filters.
WIRELESS POWER TRANSFER:
• Basics of wireless power transfer. Equivalent circuits for wireless power transfer systems consisting of coupled resonant inductors. Relationship with the equivalent circuit of filters. Equivalent circuits of filters obtained with coupled inductors.
DESIGN WITH CAD
• Basics on the coupling matrix.
• Exercise: Synthesis of a 5-pole filter and calculation of the parameters of the equivalent circuit with half-wavelength transmission lines and impedance inverters. Writing a Matlab script that implements the formulas. Sizing of irises that implement impedance inverters through full-wave simulation.
• Exercise for calculating the parameters of a filter with inverters and dispersive transmission lines. ADS simulation of the calculated equivalent circuit.
• Design of a microstrip filter using HFSS.
• Construction of a rectangular waveguide microwave filter designed by the student and made using a 3D printer.
RADAR:
• Brief history of RADAR. Notes on the Magnetron. Derivation of the radar equation. Classification of radar systems. Examples of radar images.
• Probability of detection and false alarm. Integration over the number of pulses to reduce the probability of error. Inclusion of system losses in the radar equation. Insights on radar cross-section and its physical meaning. Radar cross-section of a sphere. Overview of possible targets and order of magnitude of the relative radar cross-section. Variability of radar cross-section with frequency. Notes on stealth technology.
• Pulse radar and its operating principle. Block diagram of the pulse radar. Calculation of range and maximum range. Continuous wave radar (doppler); operating principle and block diagram. Operating principle of frequency-modulated continuous wave radar: case of a stationary target and moving target. Block diagram of the modulated continuous wave radar.
• Tracking radar. Sequential lobing. Conical scan. Monopulse tracking and its block diagram. Use of the hybrid junction in monopulse.
• 4-antenna monopulse for elevation and azimuth tracking. Example of Ka-band monopulse. Operating principle of MTI (Moving Target Indication). Improvement factor, single canceller MTI.
• Blind speed. Double canceller MTI. MTI with frequency-shaped filters. Range-gated doppler filters. Blind phase. MTI comparison between analog and digital technologies.
• Synthetic Aperture Radar (SAR) operating principle and observation geometry. Cross-track resolution. Pulse compression radar (chirp signal) for increasing cross-track (azimuthal) resolution. Demonstration with a homemade sonar obtained by programming in Matlab to show the operating principle of signal compression (chirp signal).
• SAR azimuthal resolution: synthetic aperture length. Synthetic aperture time. Azimuthal bandwidth. Calculation of SAR azimuthal resolution.
• Discrimination of ground points: isodoppler lines and isorange line. Spotlight SAR. Interpretation of SAR images. Foreshortening, layover, and shadowing. SAR image of a bridge and interpretation of the image due to multiple reflections. SAR interferometry: height estimation and surface change estimation.
• Example of a radar system with site and structure visualization. Overview of technical characteristics in relation to radar use. Example of SAR radars mounted on aircraft and spacecraft.