|SCIENTIFIC DISCIPLINARY SECTOR||ING-INF/03|
|MODULES||This unit is a module of:|
Physically grounded channel modeling techniques for mobile communications.Effects of Hertzian channels on transmitted radio signals by using deterministic and probabilistic models for single and multi-user mobile systems. Main modulation techniques for mobile comms. including CDMA and OFDM. Radio systems simulation models, including digital receiver structure and techniques. Software Defined and Cognitive Radio and seminars on advanced spectrum sensing in SDR.
Mathematical models for radio transmission: (20) Radio Channel models; Free space model; Probabilistic rain model; Multipath time-variant general statistical model (Time variant pulse response, First order channel models (Fading (Rayleigh, Rice, Nagakami)); Second order models. Radio transmission system models: Frequency selectivity and temporal fading; Slow and fast fading; Diversity transmission (frequency, time, space); Wideband transmissions as frequency selective channels; Channel models and rake receivers. Wideband Digital radio transmission: systems and techniques (20): Multiple Access techniques overview; Wideband modulations: Spread Spectrum: General concepts, Direct Sequence Spread Spectrum and CDMA, Orthogonal Frequency Division Modulation (OFDM) Software and Cognitive Radio (10) : Software radio architectures;. from software to cognitive radio
To acquire knowledge on methods and techniques related to:
Mathematical models for radio transmission:
Basic Radio Channel models; Free space model; Probabilistic rain model;
Multipath time-variant general statistical model (Time variant pulse response, First order channel models (Fading (Rayleigh, Rice, Nagakami)); Second order models. Radio transmission system models: Frequency selectivity and temporal fading; Slow and fast fading; Diversity transmission (frequency, time, space); Wideband transmissions as frequency selective channels; Channel models and rake receivers.
Wideband Digital radio transmission: systems and techniques
Multiple Access techniques overview; Wideband modulations: Spread Spectrum: General concepts,
Direct Sequence Spread Spectrum and CDMA,
Orthogonal Frequency Division Modulation (OFDM) Software and Cognitive Radio
Software radio architectures;. from software to cognitive radio
To acquire capabilities of programming by means of labs using matlab and wireless sw development tools
The course is divided in two parts.
Lectures in frontal teaching modality presented together with slides will aim at describing the theroretical concepts and the techniques. Such lectires will cover 40 hours and can be recorded and made available on those channels recommended by Univeristy of Genova.
The second part is done within a laboratory carried on by an expert of the field and will involve application of programs in Matlab and GNU radio framework that correspond to theories and techniqeus shown at lectures. Students will be required to present a short report at the end of each lab experience.
10 Lab experiences are planned and will help students to link theoretical concepts to practical laboratory programming experiences.
Multiple Access techniques: FDMA, TDMA, FD-TDMA
CDMA. Comparison with FD/TDMA.
2. Wireless channel models
Circuital model for radio links
Free space model.
Isotropic and directional antennas.
Transmitted Power 3D propagation
Deterministic and statistical channel models.
Additional loss from earth surface propagation, LOS; atmosphere effects
Statistical attenuation channel model: rain and shadowing
Multipath channel model
Equivalent low pass signal representation
time variant pulse response,
Rayleigh, Rice, Nagakami fading models
Second order and first order models.
Fading models; multipath Intensity profile and delay spread, coherence bandwidth.
Time variant channel model: Cross correlation channel model time-frequency spaced.
Doppler power spectrum, Doppler spread and time coherence
Frequency not selective channel model
Frequency selective channels. Tapped delay line model
Rake receiver for frequency selective channels.
2. Wideband modulation techniques for wireless channels
Architectures Spread spectrum: features and modulation technique design objectives
Direct sequence Spread spectrum and Frequency Hopping as Spread spectrum techniques
Multiple user interference: Gaussian and not white noise case.
Multiple user receiver for CDMA over wireless channels: MAP and maximum likelihood receiver
Multiple user interference in CDMA systems: MUI approximation as Gaussian and white noise
Multiuser DS CDMA detectors: optimal and Viterbi detector
Suboptimal multiuser detectors for DS-CDMA: conventional, Decorrelating and MMSE receivers
DS CDMA Kasami sequences
Coarse acquisition methods: Matched filter correlator, Sequential search, RASE
Tracking: DLL, Tau Dither loop
OFDM overview and signal description. Multiple carriers and orthogonality
OFDM: bandwidth and OFDM analog transmitter scheme
OFDM digital modulator and demodulator using DFT Digital spreading for DS SS; PN Gold sequences
OFDM: Guard interval for multipath channels OFDM performances in white noise: Equalization
OFDM:, differential modulation, interleaving, effects of frequency and phase eroors
OFDM synchronization. phase and time disalignments
3. Software Defined Radio
History of Radio;
From software capable to cognitive radio
SDR: Base station and terminal architecture
ADC and DAC, Down and upconverters, Processors for SDR
Software Communications Architecture
Super Heterodyne, Direct conversion Bandpass Sampling
4. Laboratory experiences
Introduction to Matlab for Physical layer radio models
AM modulation using GNU radio environment
Multipath Channel model
Spectrum sensing for Cognitive Radio
Direct sequence Spread spectrum
CDMA over wireless channels
OFDM signal and transmitter
OFDM in multipath environments
Presentation of possible thesis topics
Slides of all lectures will be made available on Aulaweb. Recording of lessons if available will be also provided.
Books and research papers that can help the student to integrate concepts described during frontal activity are here provided and can be integrated during the year.
G. L. Stuber, Principles of Mobile Communication, Kluwer Academic Publishers, New York, 1996
T. Rappaport, “Wireless Communications: Principles and Practice, 2nd Edition”, Prentice Hall, USA, 2001
J.G.Proakis, “Communication Systems Engineering, 2nd Edition”, Prentice Hall, New Jersey, 2001
Cognitive Radio, Software Defined Radio, and Adaptive Wireless Systems, Ed.,Hüseyin Arslan, Springer, Netherlands, 2007
The exam for this module is oral.
In case of remote exam is necessary or mandatory exam will be oral and done by using Teams platform.
Otherwise, exam will be in presence In that case, upon request, the oral exam can be divided in two parts: a written pre-assessment based on a set of questions to be answered in one hour followed by a oral discussion.
The written part can be substituted by a lab on line exercise in sessions immediately after the end of the course lessons.
The oral discussion will cover all the course program. A first set of questions will be oriented to evaluate knowledge and capabilities of the student on modeling and choosing parameters for a wireless channels for a generic wireless transmission system. The second part of the exam will assess wideband modulation techniques and characteristics of Software Defined Radio architectures.
Official exam dates are provided by course calendar. In addition, it is possible to schedule additional exams on per-appointment basis, depending on a number of interested students and professor's availability.
In both cases (official and unofficial exam dates), if you wish to attend an exam, please send an e-mail to:
at least one week before the exam
Students with learning disorders ("disturbi specifici di apprendimento", DSA) will be allowed to use specific modalities and supports that will be determined on a case-by-case basis in agreement with the delegate of the Engineering courses in the Committee for the Inclusion of Students with Disabilities
Exam aims at assessing the following aspects about acquired student's knowldge and capabilities:
Level of Knowledge acquired with respect to theories and methods presented in course lectures
Level of Capabilities when selecting appropriate parameters and comparing alternative choices for different wireless channel models and modulation techniques
Knowledge and capabilities will not be centered on mnemoninc listing of concepts, methods and formulas, but on the capability to describe also in amathematical probabilistic way signal transformations along the transmission and signal processing characteristics of modulation techniques