35167 - COMMUNICATION SYSTEMS: THEORY AND MEASUREMENT M

Conoscenze e abilità da conseguire

Al termine del corso, lo studente possiede conoscenze sulla trasmissione digitale con particolare riferimento ai sistemi wireless terrestri e satellitari. Nello specifico, lo studente è in grado di dimensionare un collegamento wireless, conosce le problematiche di modulazione e demodulazione digitale, gli effetti di propagazione anomala e relative tecniche per la loro mitigazione, incluse quelle multi-portante (OFDM) e multi-antenna (MIMO). In aggiunta, lo studente possiede conoscenze di simulazione e analisi in laboratorio dei sistemi di comunicazione digitali.

Contenuti

Module 1 - Prof. Alessandro Vanelli-Coralli

Course Introduction and Communication Systems Overview

1. Introduction to the course: Objectives, structure, and learning outcomes
2. Communication systems: wireless and wired communications; cellular communications; Non-Terrestrial Networks communications; The channel link capacity.

Communication Systems Fundamentals

1. Mathematical background for wireless systems: Real and complex Gaussian random variables. Rayleigh, exponential, and chi-square statistics. Real and complex Gaussian vectors. Basic matrix algebra, eigenvalue decomposition, and singular value decomposition (SVD).
2. Digital communication fundamentals: PAM, sampling theorem, and reconstruction; Noise in Communication systems; Baseband vs. passband signals; Modulation and demodulation concepts, quadrature representation.
3. ISI in bandlimited channels: Nyquist criterion, raised cosine filtering
4. Link budget fundamentals: Path loss models, received power calculation
5. Wireless channel: Wireless channel characteristics (free space propagation, path loss, shadowing, and multipath). Time and frequency selectivity (coherence time and bandwidth, Doppler spread and delay spread). Multipath propagation modeling (tapped delay line model, channel impulse response). Statistical channel models (Clarke model, Rayleigh fading, Jakes spectrum, and Rician fading)

Detection Theory Fundamentals

1. Introduction to detection theory: Hypothesis testing, Maximum A posteriori and Maximum Likelihood decision criteria in communications
2. Examples and exercises: Binary detection problems

Optimal Transmission in Bandlimited Non-Selective AWGN Channels

1. Linear modulations: Signal space representation, constellation diagrams, and spectral characteristics
2. Common modulation schemes: L-ASK, L-PSK, M-QAM analysis and comparison
3. Optimal Receiver in AWGN: Matched filter and correlator
4. Spectral and energy efficiency: Trade-offs and theoretical limits (Shannon capacity)

Transmission in the Presence of Channel Selectivity

1. Transmission in the presence of flat fading: Link budget criteria in the presence of fast and slow fading: outage probability and average probability of error.
2. Optimal transmission in the presence of frequency selectivity: The MLSE receiver. Suboptimal schemes for adaptive equalization: linear equalizers.

Multiplexing and Multiple Access

1. Multiplexing and multiple access techniques
2. OFDM principles: Orthogonality, cyclic prefix, and DFT implementation
3. OFDM advantages and limitations: Frequency selective channels, Spectral efficiency, Complexity, Peak-to-average power ratio, synchronization sensitivity
4. OFDM applications in 4G, 5G and 6G

Multi-Antenna Systems - Introduction

1. MIMO system definitions: Spatial diversity and multiplexing concepts
2. SIMO systems: Maximal ratio combining (MRC) and selection diversity
3. MISO systems: Transmit diversity and basic beamforming (Alamouti scheme)
4. MIMO capacity: Brief introduction to spatial multiplexing gains

Module 2 – Prof. Gianni Pasolini

· Laboratory activity

1. Introduction to Matlab simulation software
2. Design and implementation of functional blocks for the generation of modulated signals
3. Design and implementation of functional blocks for the decoding of modulated signals
4. Use of software defined radio devices

Testi/Bibliografia

Slides and note of teh course will be made available during the courses

Suggested readings

• D. Tse and P. Viswanath, "Fundamentals of Wireless Communications", Cambridge University Press, 2005.
• A. Goldsmith “Wireless Communications”, Cambridge University Press, 2005
• J.Proakis, “Digital Communications”, Mc Graw Hill.

Metodi didattici

The course is composed of 2 modules for a total of 9 CFUs, of which 6 CFUs as frontal lectures (Module 1, Prof. vanelli-Coralli) and 3 CFUs as experimental activity (Module 2, Prof. Pasolini).

The experimental activity takes place in the laboratory with the objective to let the student familiar with the design and simulation tools (Matlab) used to generate and measure modulated signals. The activity is organized in groups of 2-3 students each.

In consideration of the type of activity and teaching methods adopted, the attendance of this training activity requires the prior participation of all students in modules 1 and 2 of training on safety, [https: //elearning-sicurezza.unibo .it /] in e-learning mode.

Modalità di verifica e valutazione dell'apprendimento

The final assessment consists of a written test and an oral interview. Both the written test and the oral interview cover both modules and all of the subject introduced during the course.

Strumenti a supporto della didattica

Educational material: Lecture notes presented in class will be available to students in electronic format through Virtuale.

Experimental activity using Matlab and laboratory instrumentation (function generator, oscilloscope, spectrum analyzer, software defined radios).

 

Students with specific learning disorders (SLD) or temporary/permanent disabilities:

We recommend contacting the University Office responsible for support services in a timely manner (https://site.unibo.it/studenti-con-disabilita-e-dsa/en). The office will evaluate the students' needs and, where appropriate, propose possible accommodations. These must in any case be submitted for approval at least 15 days in advance to the course instructor, who will assess their suitability also in relation to the learning objectives of the course.

Orario di ricevimento

Consulta il sito web di Alessandro Vanelli Coralli

Consulta il sito web di Gianni Pasolini