Mobile Radio Networks

The course aims to achieve the following objectives, in line with the Dublin descriptors:

1. Knowledge and understanding:

• Knowledge of the technologies used in mobile networks, which differ considerably from those adopted in fixed networks due to the characteristics of the radio transmission medium and the problems of managing users' mobility. Knowledge of the methodological tools necessary to analyze system-level performance.
• Knowledge of the standards currently operational or soon to be implemented, describing the architecture of the networks on the basis of fundamental operational concepts. Specific understanding of resource management, terminal mobility, and security in mobile networks.

2. Ability to apply knowledge and understanding

The student will be able

• to carry out the planning and sizing of a mobile network both through radio propagation and traffic engineering considerations;
• to optimize existing protocols for new application scenarios.

3. Making judgements

In the context of the topics covered in the course, the student will be able to make the appropriate design choices based on specific requirements independently. 

4. Communication skills

The student will acquire the ability to rationally communicate knowledge on mobile cellular networks and to correctly use the related technical language.

5. Learning skills: students will be able to independently read standards and scientific literature of the sector, in order to update themselves on the fast evolutions of mobile radio technologies and to deepen complex issues.

The course takes place through lectures (49 hours) performed both on the blackboard and with the aid of personal computers through which slides can be projected.

There are also 15 hours of exercises in which students are often invited to carry out the proposed exercises under the guidance of the teacher, in order to stimulate collective attention and also to obtain a 'sample' evaluation of the learning results.

In addition, 15 hours of laboratory activities are foreseen.

If the teaching is given in a mixed or remote mode, the necessary changes may be introduced with respect to what was previously stated, in order to comply with the program envisaged and reported in the syllabus.

The topics covered in the courses "Theory of Signals", "Digital Communications" and / or "Fundamentals of Telecommunications",  "Internet", and "Communication Theory and Systems" are preparatory to the subject.

In particular the knowledge of multiplexing and switching techniques; the concepts of protocol architecture, signaling, control / user plan; the theory of traffic and queues, use of Erlang's formula B; propagation in the radio section; link budget; multi-layer modulation; noise figure; relationship between BER and SNR; source and channel coding principles.

Attendance is not mandatory.

Attendance is however strongly recommended as the carrying out of the exercises and the laboratory activity favors the understanding of the topics covered.

1. Introduction and basic concepts on mobile networks. Classification, motivation, and requirements of mobile networks. Evolution of mobile networks and services. Mobile network architectures. Sharing of radio resources. The mobility of users.

2. The radio channel and radio transmission. Radio channel and propagation models. Outline of numerical modulation and channel coding schemes. Cell sizing with radio propagation considerations.

3. Radio access. Multiple access techniques in broadcast channels. Duplexing. Radio resource sharing models.

4. Mobility Management and Mobile Performance Analysis. Cell selection, location management, handover. Traffic models and mobility models for call-level performance calculation.

5. Radio planning.: cellular coverage and network capacity. Frequency reuse. Planning a cellular system with traffic engineering considerations.  Capacity analysis.

6.  GSM. Architecture and radio interface; physical and logical channels; management of mobility, radio resources, and security; reporting protocols; examples of procedures; supported services.

7.  Notes on GPRS. Architecture and protocols of the GPRS network: comparison and updates with respect to the GSM architecture. GPRS radio interface.

8.  UMTS. Architecture and radio interface; power control; management of radio resources, mobility, and security.

9. LTE.Main features and performances offered by the new technology. Network and service architecture. Interfaces and protocols. LTE radio interface.

10. 5G. Towards 5G: from LTE-Advance to LTE-Advance Pro. 5G Usage scenarios and requirements. QoS architecture and model. 5G New Radio. 5G RAN & 5G Core

Laboratory. The experiences in the laboratory are an integral part of the course and will be carried out at the DIEEI Technological Pole with variable frequency (depending on the progress of the program). Some issues addressed are listed below.

• Computer implementation of indoor and outdoor cellular transmission scenarios, path loss models (free space, Okumura-Hata, 3GPP models), and channels affected by fading.
• Computer implementation of heuristic algorithms for  power control in CDMA systems and allocation of radio resources in LTE systems.
• Introduction to testing software to perform network parameter measurements for GSM, UMTS and LTE systems. Analysis of cell attach, cell reselection, location update, generated and received calls procedures.
• Introduction to the software and hardware available in the laboratory to emulate an LTE mobile network. Network performance analysis in streaming services and download / upload on FTP server. Analysis of the exchange of signaling messages both on the access network and core network side. Resource Block allocation and Modulation and Coding Scheme as the distance and quality of the channel vary.  Call evaluation on VoLTE technology.

Should the teaching be given remotely, the necessary variations with respect to the specific laboratory activities declared may be introduced.

1. Martin Sauter, “From GSM to LTE‐Advanced Pro and 5G: An Introduction to Mobile Networks and Mobile Broadband”, IV Edition , John Wiley & Sons Ltd, 2021
2. M. Schwartz, “Mobile Wireless Communications”, Cambridge University Press.
3. C. Cox, “An introduction to LTE: LTE LTE-Advanced, SAE, VoLTE and 4G Mobile Communications”, 2° Edizione, Wiley.
4. Christopher Cox, “An Introduction to 5g: The New Radio, 5g Network and Beyond”, John Wiley & Sons Ltd, 2020
5. Rajib Taid, “Mobile Communications Systems Development: A Practical Introduction to System Understanding, Implementation, and Deployment”, John Wiley & Sons Ltd, 2021,

Handouts of the teacher's slides available on Studium

The exam to evaluate the student's preparation consists of two written tests:

• The 1st test (on dates indicated in the official exams calendar) involves solving numerical exercises.
• Students who pass the 1st test with a rating of at least 15/30 are admitted to the 2nd test, on a date agreed with the teacher, which includes open-ended theoretical questions that will be immediately discussed and evaluated.

Learning verification can also be carried out electronically, should pandemic conditions require it.

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During the course, it will be to carry out a non-mandatory mid-term test with numerical exercises and theoretical questions, relating to the first part of the program. This mid-term test, if passed, allows access, exclusively during the first exam session, directly to the 2nd test with a reduced program. In particular:

• For those who pass the mid-term test with an A grade, the 2nd test will focus exclusively on the remaining part of the program. 
• For those who pass the mid-term test with a B grade, the 2nd test will include, in addition to the remaining part of the program, a question (numerical or theoretical) on the gaps shown in carrying out the mid-term test.

• Describe the Multipath phenomenon and an example of its impact.
• How do you get the distance of a mobile user from the GSM base station to which he is connected.
• Is there a link between power control and admission control in CDMA networks?
• What are the attributes of QoS in LTE systems?
• How does the Location Updating procedure take place in GSM networks?
• Describe the LTE network architecture.
• Describe the radio interface of 5G systems.

A more extensive list of possible questions and some examples of the written tests can be found on Studium, in the Teaching Documents section