Wireless Communications and Mobility

• Communication Systems;
• Electromagnetism;
• Antennas and Propagation.

Teaching methods: Presential

Theoretical classes are essentially expository, in which the teacher presents the fundamental concepts associated with current radio communication systems and wireless networks.

In laboratory classes, direct contact with real scenarios and existing technologies is privileged. Students have to carry out in group, three practical assignments and a micro project of medium complexity.

Objectives: To acquire knowledge in the area of ​​radio technologies: mobile communications systems; wireless networks; IoT and satellite radio navigation systems.

Generic skills: Ability to analyze and synthesize; ability to develop autonomous and / or team work; ability to apply technical knowledge to develop innovative wireless communication and IoT solutions radio localization applications; ability to speak and write in Portuguese.

Specific skills: Know the basics of mobile communication systems and wireless networks; know the principles underlying the propagation of electromagnetic waves; understand and apply the main radio propagation models to determine the coverage of radio systems; know, design and develop communication applications on mobile networks and / or wireless networks using transceivers and micro-controllers; develop radio location applications using GPS receivers.

Introduction

• Radio systems: classification; frequency bands; services
• Wireless communications history
• Radio access technologies
• The future of wireless communications systems: 5G and beyond

Radio Wave Propagation Introduction

• Electromagnetic wave propagation fundamentals
• Interference; reflection; refraction; diffraction; scattering; absorption; etc.
• Free-space propagation model; ground reflection (two-ray) model
• Fading and multipath
• Okumura-Hata and COST 252 propagation model

Mobile Cellular Systems

• Cellular and pre-cellular systems
• Frequency reuse concept
• Interference and system capacity
• Cell split; sectorization; frequency hopping; dynamic power control; DTX and antennas tilting
• Mobility and handover

Current Cellular Communication Systems

• Global System for Mobile Communications (GSM) 
• GSM Phase 2+ Systems: HSCSD, GPRS and EDGE
• LTE (Long Term Evolution) and LTE-Advanced Systems
• Topics on 5G Mobile Communication Systems

Trunking Theory

• GoS (Grade of Service) and QoS (Quality of Service) metrics
• Traffic intensity, Erlang definition
• Arrival calls distribution and service distributions:
• Trunking systems: Erlang B and Erlang C formulas

Wireless Data Networks

• WLANs based on IEEE 802.11 a/b/g/n/ac standards and Wi-Fi 6
• WPANs based on the IEEE 802.15.4 standard

LoRaWAN (Long Range Wide Area Network)

• CSS modulation and LoRa physical layer parameters
• Radio link budget and trade-offs: coverage range vs. data rate vs. energy consumption
• LoRaWAN network architecture and components
• Device classes, activation procedures, and security
• IoT Platforms (TTN/TTS), practical applications, and case studies

Proprietary radio solutions and applications

• Topics on RFID Systems: warehouse product management, security, and access control
• Topics of Satellite Radio Navigation Systems and fleet management

Evaluation method: Evaluation by a written exam (official designation "Avaliação por exame")

Formal written exams, laboratory work and a micro project for all enrolled students.

The Final Grade (FG) f the unit is obtained from the following components: Written exam to be carried out at the end of the semester and a laboratory component that includes several laboratorial assignments and a micro project.

The FG is the weighted average of the referred components according to the equation

FG  = 0.7 x Exam + 0.3 x PL

To obtain successful in this unit, it is necessary to obtain a minimum weighted FG of 9.5 values (out of 20), and it is necessary to obtain a minimum grade equal to:

•   8.5 / 20.0 points (42.5%), in the final written exam;
• 10.0 / 20.0 points (50.0%), in practical work.

Only students who attend at least 78% of the laboratory classes effectively taught are eligible to access the examination.
(The number of unjustified absences in the laboratory component may not exceed three.)

Practical work is carried out during class time and, as a general rule, in groups of two students.
The assessment of this component includes an individual oral defense of the reports, to be held in the last laboratory class of the semester.
The micro-project is developed during the last two laboratory classes of the semester.
Some of the tasks associated with the micro-project, namely the preparation of the report, may be carried out outside scheduled class hours.
The micro-project will be made available in the 11th teaching week, and its submission and defense will take place in the final teaching week of the semester.
Working students who, for duly justified reasons, are unable to attend laboratory classes must contact the lecturer responsible for the course unit in the first teaching week of the semester, in order to define alternative assessment arrangements for this component.

NAO