Courses

 Introduction to Information Systems, conceptual framework. Categories of Information Systems and areas of application. Fundamental skills of Information & Communication Systems Engineers. Introduction to circuits. MOS transistors and logic gates. Introduction to Computer Architecture. Introduction to Computer Networks. Introduction to Internet and Web Technologies. Social and legal aspects of information and communication technologies. HTML and CSS languages. Current trends and challenges.

Introduction: Analog and Digital Signals, Usefulness of Digital Signal Processing and Digital Circuits, Evolution of Digital Circuits. Digital Systems and Binary Numbers: Digital Systems, Binary Numbers, Number-Base Conversions, Octal and Hexadecimal Numbers, Complements, Signed Binary Numbers, Binary Codes, Binary Storage and Registers, Binary Logic. Boolean Algebra and Logic Gates: Basic Definitions, Axiomatic Definition of Boolean Algebra, Basic Theorems and Properties of Boolean Algebra, Boolean Functions, Canonical and Standard Forms of Boolean Functions, Other Logic Operations, Digital Logic Gates. Gate-Level Minimization: The Map Method, Three, Four and Five-Variable Maps, Product-of-Sums Simplification, Don't-Care Conditions, NAND and NOR Implementations, XOR Function. Combinational Logic: Combinational Circuits, Analysis Procedure, Design Procedure, Binary Adder-Subtractor, Binary Multiplier, Magnitude Comparator, Decoders, Encoders, Multiplexers, Tri-State Gates. Synchronous Sequential Logic: Sequential Circuits, Latches, Flip-Flops, Analysis of Clocked Sequential Circuits, State Reduction and Assignment, Design Procedure. Registers and Counters: Registers, Shift Registers, Ripple Counters, Synchronous Counters, Other Counters.

Basic principles of electric circuits – levels of functional abstraction. Resistive network analysis techniques: Kirchhoff's Laws, series and parallel simplification. Network theorems: the Node method, Superposition. Equivalent circuits: the Thévenin equivalent network, the Norton equivalent network. Circuit transformations. Digital logic – noise margins. The MOSFET switch – design of digital gates. Input - Output behavior of digital gates. Capacitors and inductors: basic principles, series and parallel connections. First-order circuits: Resistor-Capacitor (RC) circuits, Resistor-Inductor (RL) circuits, analysis of first-order circuits. Physical structure of the MOSFET. Propagation delay of digital gates. Energy and power in digital circuits: energy calculation, Static power dissipation, Dynamic power dissipation. CMOS logic.

Introduction to computer communication. Network achitecture and protocols. Network Design. The OSI reference model from ISO. Transmission media (coaxial cable, fiber optics). Principles of data transfer. Local and metropolitannetworks. Static and dynamic channel allocation. The ALOHA protocol. The CSMA protocol. The family of IEEE 802 for local networks (Ethernet, Token bus, Token Ring). The optical FDDI network. Design and analysins of data link layer. Error detection and correction. Flow control. The wireless ΙΕΕΕ 802.11. Networking devices (switches, routers, etc.).

Basic definitions of signals and systems, periodic signals, unit step function, impulse function. Categories of systems, static and dynamic systems, causal and non-causal systems, linear and non-linear systems, time invariant and variant systems. Impulse response of linear systems. Convolution properties. Stability of systems. Direct and inverse Fourier transform. Convergence and properties of the Fourier transform. Application of the Fourier transform in the study of linear systems, system frequency response, description of Linear Time Invariant (LTI) systems with differential equations and the Fourier transform, ideal lowpass filter. Fourier series, Fourier series of periodic functions, Fourier series for even or odd symmetry, Parseval’s theorem. Laplace transform, properties and theorems. Inverse Laplace transform. Bilateral Laplace transform. Use of the Laplace transform for solving linear differential equations. Use of the Laplace transform in the analysis of linear systems and the study of their stability. Discrete-time signals and systems, direct and inverse Z transform and its properties. Unilateral Z transform. Discrete-time Fourier transform. Sampling – Nyquist theorem. Discrete Fourier transform.

Nonlinear elements and circuits. Analysis of nonlinear circuits: analytical solutions, graphical analysis, piecewise linear analysis, incremental analysis. Diodes: semiconductor diode characteristics, analysis of diode circuits, method of assumed states. Dependent sources and the notion of amplification. Actual MOSFET characteristics – the Switch Unified (SU) MOSFET model. The MOSFET amplifier: biasing the MOSFET amplifier, the amplifier abstraction and the saturation discipline. Large-signal analysis, operating point selection. Small-signal analysis. The Operational Amplifier (Op Amp): the Op Amp model, the non- inverting Op Amp, the voltage follower, inverting Op Amp, simplified method for analyzing circuits with Op Amps, adder, subtracter, differential amplifier. Analog-to-Digital and Digital- to-Analog conversion.

Introduction to Operating Systems: basic concepts, history, operating system structure. Processes: the process model and implementation of processes, interprocess communication (race conditions, critical regions, mutual exclusion), process scheduling. Threads: the thread model and thread usage, implementation of threads in user space and in the kernel, hybrid implementations, pop-up threads, making single-threaded code multithreaded, thread scheduling. Deadlocks: detection and recovery, deadlock avoidance, deadlock prevention. Memory management: swapping, virtual memory, page replacement algorithms, design issues for paging systems, implementation issues, segmentation. Input/Output (I/O): principles of I/O hardware, principles of I/O software, I/O software layers, disks. File systems: files and directories, file system implementation, security and protection mechanisms.

Reference Model TCP/IP and the OSI. IP Layer. Addressing. Algorithms and routing protocols. IPv6 and mobile IP. Congestion Control. Methods open (shaping, leaky backet etc.) and closed loop (blocking etc.). Internetworking, virtual networks, firewalls. Transport Layer. TCP & UDP Protocols. Multimedia applications and networks.

Transmission methods, telecommunication system model. Statistics and stochastic processes in telecommunications. Hilbert transformation. Baseband transmission and band-pass signals. Analog Modulation AM, FM and PM, spectrum analysis, noise. Signals and Systems in Telecommunications. Fourier series and transform. Filters' classification, Distortion free transmission, Noise, Analog and/or digital data transmission over analog and/or digital systems. Sampling and quantization. Bandwidth, Nyquist and Shannon theorems. PAM and PCM modulations. Digital modulations (ASK, PSK, FSK, M-QAM).

Characteristics of a digital communications system. Characteristics of telecommunications channels. Mathematical models of telecommunications channels. Coding of discrete information sources: PCM, differential PCM, adaptive PCM. Binary representation of signals: PAM, PSK, QAM, FSK, CPFSK, MSK. Spectral characteristics of digitally modulated signals. Optimal receiver for white Gaussian noise. Bit error rate performance of the optimal receiver for different digital modulation techniques. Synchronization. Inter-symbol interference. Orthogonal Frequency Division Multiplexing (OFDM). Multiple Input/Multiple Output (MIMO) transmission.

Basic concepts and principles of Distributed Systems,
Middleware and resources, Client-Server Model,
3-tier Model,
Models of communication and programming models (distributed transaction, remote procedure call, remote method invocation, message queue), Name Services (Domain Name System, directory services),
Synchronization (logical clocks, distributed mutual exclusion, leader election, global states),
Consistency and replication,
Fault Tolerance.

Application Specific Integrated Circuits (ASICs) and programmable devices (PLAs, PLDs, FPGAs), Hardware Description Languages (HDLs): Verilog and VHDL. Introduction to Verilog HDL, designing digital circuits with Verilog, Verilog syntax, modules and ports, structural modeling, behavioral modeling, dataflow modeling, tasks and functions. Finite State Machines (Mealy and Moore), Verilog for synthesis, design of sequential modules. Timing and delays in Verilog, Computer Aided Design (CAD) tools, logical simulation and timing verification. Random Access Memories (RAMs) and memory interfaces. Design prototyping.

Discrete information sources, alphabets. Entropy. Source coding: Huffman codes, Lempel-Ziv, arithmetic codes. Channel capacity. Second Shannon’s theorem. Binary symmetric channel. Source modeling with Markov chains. Modulation and channel restrictions. Sequences (d, k) and codes RLL. Linear error detection and error correction codes. Codes representation in a binary vectorial space. Hamming distance. Decoding of linear codes. Codes Hamming: design, binary code, extended Hamming codes. Performance bounds of linear codes. ARQ protocols. This course offers an introduction to the theory of information and its applications to communication systems. Emphasis is given on the design, analysis and application of error detection and correction codes.

Introduction to Multimedia. Basic multimedia concepts, current state-of-the-art. Multimedia content generation. Digital data acquisition: analog and digital signals, analog-to-digital conversion, signals and systems, sampling theorem and aliasing, filtering, Fourier analysis. Media representations and media formats: digital image representation, aspect ratio, digital image formats, digital video representation, video signal type, YUV subsampling schemes, digital video formats, digital audio representation, surround sound, spatial audio, commonly used audio formats. Color theory: trichromacity theory, color spaces. Multimedia compression: the need for compression, basic information theory concepts, lossless and lossy compression. Image compression: redundancy and correlation of image data, lossless image coding, transform image coding, wavelet based coding. Video compression: general video compression theory (temporal redundancy, block-based frame prediction, motion vectors' computation, macroblock dimensions), prediction types, video coding standards. Audio compression: audio compression theory, audio as a waveform, audio compression using psychoacoustics, model-based audio compression, audio coding standards. Multimedia distribution. Multimedia networking: communication modes, multimedia communication standards and protocols.

Management of TCP/IP based networks. SNMP protocol. Database of Information Management. Abstract transmision syntax. Management of OSI networks. CMIP protocol. Tree of Information management. Comparison of management of OSI and TCP/IP systems. Management of bridged networks. Spanning tree algorithms. TMN prototype. Modern technics/methods of management WBM, CORBA, Java-based.

Quantitative analysis of discrete-event systems, including computer systems and networks, both by statistical models and tools, and by simulation. Poisson, birth-and-death and Markov processes, and their application to modelling and performance evaluation. Queueing theory: M/M/1, M/M/c, M/M/1/K, M/M/1/K/K models; application to modelling a network node. Queueing networks, Jackson networks, BCMP networks; application to modelling communication networks. Computer system models, including the central server model. Simulation of discrete-event systems using Arena. Case studies: latency in multiprocessor systems, modelling and simulation of sensor networks, user modelling.

The course is an in-depth study of the analysis and operation of technological, economic and social networks. The course material aims to analyze different types of networks such as wireless, internet, content distribution, world wide web, social networking, and online economics. It refers to specific contexts in the analysis of networks such as Aggregation and Impact, Distributed Coordination, Feedback Control and Strategic Balance. It utilizes modeling languages and analysis mechanisms from four fields of applied mathematics, namely Graph Theory, Optimization Theory, Game Theory and Learning Theory. In this sense, the course utilizes knowledge from previous general and specific courses of directions in order to examine networks between devices and between people, illustrating important ideas and useful methodologies for the two types of networks. It introduces notable parallels to the underlying analytical models as well as key differences based on the specificities of each region.

Types of programming languages.
Variables, expressions and commands.
Datatypes and type definition systems.
Scope and time of memory binding.
Procedures.
Exception handling.
Concurrency.
Object-oriented programming languages.
Introduction to the organization and operation of compilers.
Lexical analysis.
Syntax directed translation.
Basic detection techniques.
Symbol tables.
Intermediate code.

Cloud computing technologies, types of services (NaaS, IaaS), development models (private, public, hybrid), tools (openflow), virtualization of networking services and functions (SDN, NFV). Advanced technologies for access and core networks (e.g., ΙΕΕΕ 802.1Χ, 802.21, 5G, DSL, Gigabit Ethernet), architectures (eg. MPLS, Diffserv, IntServ), protocols (eg. RSVP, Mobile IP, IPv6, OSPF, BGP) and services (WebTV, IPTV, P2P, V2V).

Introduction: what is Digital Image Processing (DIP), fields of using DIP. Digital image fundamentals: elements of visual perception, light and electromagnetic spectrum, image sensing and acquisition, sampling and quantization, mathematical tools used in DIP. Intensity transformation functions. Histogram processing. Spatial filtering, smoothing and sharpening spatial filters. Filtering in the frequency domain: sampling and the Fourier transform of sampled functions, 2-D Discrete Fourier Transform and its properties, filtering in the frequency domain, smoothing and sharpening frequency domain filters. Image restoration: noise models, restoration in the presence of noise only, linear position-invariant degradations, estimating the degradation function, inverse filtering, Minimum Mean Square Error (Wiener) filtering. Image compression: fundamentals (coding, spatial and temporal redundancy, irrelevant information, measuring image information, etc.), basic compression methods (lossy and lossless). Color image processing: color models, pseudocolor and full-color image processing, image segmentation based on color, noise in color images, color image compression.

Client-server model vs. P2P model, BOOTP and DHCP protocols, The Domain Name System (DNS), Differentiated Services (DiffServ) protocol and Resource ReSerVation Protocol (RSVP), Virtual Private Networks (VPN), Mobile IP and mobility management in Next Generation networks, Software-Defined Networking – SDN, Network Function Virtualization – NFV, Cloud Infrastructures and Services, Multicasting and Network coding, Data transmission over power line transmission networks, Visible Light Communication Networks, Machine to machine M2M networks over internet, Green Technologies In Next-Generation Networks, Fiber Optic Internet Technologies.

Introduction: MOS transistors, CMOS logic, basic gates and memory elements, CMOS fabrication and layout. MOS transistor theory: ideal (long-channel) I-V characteristics, C-V characteristics, non-ideal I-V effects, DC transfer characteristics. Delay: RC delay model, linear delay model – Logical Effort (for a single stage and for paths), transistor sizing. Power dissipation: dynamic power, static power, energy-delay optimization, low-power circuit design. Interconnect: wire geometry, metal layers, wire modeling, delay, energy, noise, wire engineering. Process and environmental variations. Scaling. Combinational circuit design: circuit families, circuit pitfalls. Sequential circuit design: circuit design of latches and flip-flops, max-delay constraints, min-delay constraints, time borrowing, clock skew. Semiconductor memories.

Introduction: number systems and essential digital circuits. Microprocessor architecture: Principles of microprocessor systems, control unit, registers, arithmetic and logical unit, microprocessor state, microprocessors classification. Case study: 8085 architecture. Machine language and assembly. Memories and addressing modes: Organization of static and dynamic RAMs (SRAMs and RAMs) – principles of operation, reprogrammable ROMs, memory systems, addressing modes. Input/Output (I/O): program controlled I/O, polling, interrupts, Direct Memory Access (DMA). Description of 80x86 microprocessor family. More advanced microprocessors.

Introduction to wireless systems and networks. Evolution of wireless mobile communication systems. Propagation and path-loss in wireless communication. Analytical and empirical propagation path-loss models. Types of fading and channel characterization. Radio planning principles for cellular systems. Types of interference. Mobility management and handover process. Techniques for efficient allocation and management of radio resources. Digital modulation techniques for mobile communication systems and channel capacity. Medium access control protocols and multiple access techniques FDMA, TDMA, CDMA and OFDMA as well as how they are implemented in the respective wireless cellular systems GSM, GPRS/EDGE, UMTS, LTE, LTE-A. Introduction to the technological features of 5G systems.

Electromagnetic waves in space. Introduction to antenna theory and radiation mechanism. Antenna radiation regions. Field and power antenna patterns. Basic antenna parameters (gain, directive gain, directivity, temperature, etc.). Antenna equivalent circuits (transmission and reception). Reciprocity theorem and far-field radiation. Linear, loop and aperture antennas. Antenna polarization and loss factor. A generic methodology for the calculation of radiated fields. Basic antenna examples (Hertz dipole, longer dipoles, λ/2 dipole, small loops, etc.). Linear, planar and circular arrays. Noise and antenna noise temperature. Tropospheric and ionospheric waves. Ground waves. Basic wireless propagation equations (Friis, reflection, scattering, diffraction). Applications and antenna measurements.

Introduction to mobile computing, emerging mobile technologies and applications, issues and challenges, smartphone applications and services, mobile computing software platforms, mobile Web, responsive web design, geolocation, context-aware applications, Android platform architecture, programming in Android environment, case studies.

Introduction to IoT: motivations, definitions, key concepts, features, enabling technologies, challenges, applications. IoT Hardware: smart devices, sensors/actuators, h/w IoT platforms, data digitization. IoT network connectivity: Low power wireless and mobile protocols and architectures (IEEE 802.11ac/ad/ah/ax/ba, IEEE 802.15.4 and ZigBee, BLE protocols). IoT network connectivity: sensor networks, routing in sensor networks, etc. IoT network connectivity: IoT specific communication protocols, M2M/IoT networks (LoRa/LoRaWAN, Sigfox) Cloud IoT: Architecture and Implementation (Virtual Resource Pool, Database, Proxy and Load Balancing), Fog Computing: Architecture and Evaluation. IoT operating systems (Contiki, Android Things, TinyOS), IoT application level protocols (CoAP, MQTT, XMPP, HTTP RESTFUL Services, AMQP, Websockets). IoT software platforms: role, architecture, services, challenges, case studies (ThingWorx, ThingSpeak, Google Cloud IoT). Data collection, preprocessing and storage (Big data and processing of serial data by sensors). Data analysis and visualization (ML concepts, dashboards). End User Development in IoT (HCI challenges). Use Cases I: smart home, smart health precision agriculture. Use Cases II: Smart Cities, Industrial IoT.

Introduction to basic concepts of optical communication systems, optical fibers, types of fibers (single mode, multi-mode, silicon-PMMA, step-graded index), waveguiding though ray optics, Maxwell’s equations, Helmholtz equation, transversal modes, dispersion (group velocity, waveguide, chromatic), waveguide losses, bandwidth, non linear effects such as: cross phase modulation, four wave mixing. Optical sources: lasers, LEDs, spontaneous and stimulated emission, lasing threshold, longitudinal modes, tyes of lasers, noise in laser systems, modulation bandwidth and modulation techniques. Optical receivers, quantum efficiency, noise, bandwidth, sensitivity and demodulation circuits. Design and evaluate different optical system architectures in terms of power budget, optical dispersion. Analysis of coherent optical communication links and multi-channel approaches.
The course offers to the students an in-depth introduction to the field of optical-communications, by analyzing critical components such as optical emitters, receivers, optical fibers and by realistic optical links taking into consideration different technical specifications and architectures.

Introduction to satellite-link subsystems and examination of the geometrical theory of geosynchronous and geostatic satellites. Orbit mechanics. Specialized topics on the satellite channel (e.g. satellite antennas) and analysis of the satellite link in terms of radiated and received power, signal-to-noise ratios, and random effects. Analog and digital modulation and multiple access techniques and their implementation in satellite communication systems. Emphasis on the matched filter and calculation of the probability of error in digital communication systems. Detailed examination of the satellite transponder. Emphasis on transponder signal processing and the effects of nonlinearities in satellite amplifiers. Development of satellite networks based using multiple access techniques. Digital Video Broadcasting and applications.

Introduction to Matlab, performance evaluation metrics of communication systems. Signals and linear systems, representation and analysis of signals in time and frequency. Stochastic process, generation of random variables, probability distribution functions. Modeling of a digital transmitter, modulation and coding techniques. Modeling of a digital receiver, demodulation and decoding, performance evaluation of the receiver. Wireless propagation, free-space loss models. Shadowing, multipath propagation, Rayleigh fading, transmit and receive diversity. Capacity and outage probability of a wireless channel, Shannon’s formula. Cooperative relaying without and with power control. Cooperative relaying with interference mitigation, performance evaluation of interference mitigation techniques. Capacity and outage probability in networks with secrecy constraints, performance evaluation of secrecy techniques. Simulation of a Multiple-Input Multiple-Output (ΜΙΜΟ) antenna system, channel models of MIMO systems, modulation and coding for MIMO systems.