PhD in Information Technologies and their Aplication in Management, Architecture and Geophisics La Salle Campus Barcelona URL

PHD Program in Information Technologies and their Application in Management, Architecture and Geophysics

Next generation communication systems

The subject tries to give the student an overview of the newest techniques for high bit-rate, high mobility radio transmission. After an introduction to the state of the art of wireless communications and future trends, the basic parameters of a mobile communication channel are defined. Then, the main pros and cons of multicarrier modulations (in particular OFDM) are deeply studied, and special attention is paid to time and frequency synchronization. The following topic is direct sequence spread spectrum modulations in multipath channels. Finally, the hybrid combination of multicarrier modulations with spread spectrum is introduced, leading to MC-CDMA systems. Some practical systems using these techniques are studied to conclude the course. In addition to theory, the course has also two practices, about mobile channel simulation and multicarrier disadvantages simulation (synchronization, peak reduction techniques, ..), based on journal papers.
Type Subject
Previous Knowledge

Fundamentals of Digital Signal Processing, digital modulations.


The knowledge to be acquired by the students is:
1. Understanding of the different modulations used in wireless communications.
2. Understanding of articles in journals.
3. Simulation of communication systems.
The students are also supposed to develop the skills listed below:
4. Capacity for work organization and planning.
5. Oral and written communication in the native language.
6. Problem solving.
7. Computing skills for specialized software.
8. Teamwork.
9. Report writing.
10. Capacity of applying theory into practice.
11. Handling English text books. Knowledge of a second language.
12. Finding additional bibliography


1.- Mobile communications: past, present, future
3G systems
3.5G systems
Towards 4G

2.- The radio channel
The multipath delay profile
Frequency and time selectivity
Mitigation of channel effects
Channel sounding

3.- Fundamentals of Multicarrier Modulations/OFDM
Insertion of the cyclic prefix
Modulation and coding
Choice of OFDM parameters
Problems of OFDM

4.- Synchronization in OFDM
Frequency offset and window timing estimation
Channel estimation
Blind methods

5.- Spread Spectrum (SS)
Introduction to SS
Pseudo-Noise sequences
Transmitter and receiver architecture
CDMA multiple access
Multiuser detection

6.- Multicarrier CDMA
Types of MC-CDMA
Detection of MC-CDMA
Discussion MC-CDMA versus DS-CDMA
Adaptive MC-CDMA

7.- Applications
Wimax, WLAN´s
Proposals project Winner, 4MORE

1.- Simulation of the mobile channel and sounding
2.- Simulation of algorithms for time and frequency synchronization and reduction of envelope peaks in OFDM modulations.


The professor gives magisterial classes to the students, with theory and practice. Additional bibliography and slides are also available. Since the topics of the subject are quite novel, the students are encouraged to read papers in specific journals.
As far the practical work is concerned, the student has to do two simulations about the mobile radio channel and some specific topics of OFDM modulation. These simulations are based on journal papers and the students have to make an oral presentation showing the results in class.


There are different methods to evaluate the student along the course:

A. Exams.
There are two exams along the course.

B. Oral exams.
At the end of each practice an oral exam is done.

J. Classroom participation.
The professor has an observation checklist where he/she writes some behaviour and attitude of the pupils in the classrooms.

F. Team reports.
At the end of every practice, a team report has to be done showing the results and the difficulties they have found.

G. Computer work
The simulations are done in Matlab. The students have to get used to this software, as well as to simulate communication systems.

I. Oral presentations
At the end of every practice, an oral presentation in the classroom has to be done.

There are two exams along the course. The final qualification is obtained averaging the two marks, in case all of them are higher than 4.

Evaluation Criteria

Objective 1: Understanding of the different modulations used in wireless communications. The student must demonstrate he/she has acquired the knowledge about the concepts of the course. [A, B, F]
Objective 2: Understanding of articles in journals. The student has to be able to search and understand scientific bibliography to a certain extent. [F, G]

Objective 3: Simulation of communication systems. Ability to use simulation programs and knowledge of the main algorithms. [F,G]

Objective 4: Capacity for work organization and planning. The student must organise his/her own work and the collaborative work of the team. [F, G]

Objective 5: Oral and written communication in the native language. The student must present his/her exams and reports without orthographic mistakes and good style and order. [A, B, F, G, I]

Objective 6: Problem solving. The student must give good solutions in both theoretical problems and practices. [A, B, F, G]

Objective 7: Computing skills for specialized software. The student should quickly get used to new software environments. [G]

Objective 8: Capacity of work in a team. The student has to work with a team, in order to propose different solutions to the presented problems. [F, G]

Objective 9: Report writing. The student should know how to summarize the conclusions in an accurate way. [F]

Objective 10: Capacity of applying the theory into practice. The student must identify which tools should be applied in order to solve real problems. [A, B]

Objective 11: Handling English text books and knowledge of a second language. Some of the concepts are directly referenced to English textbooks. These concepts are evaluated in [A,B].

Objective 12: Finding additional bibliography. The student has to be able to find additional references to solve the problems found in their practical work. [F, G, I]

Basic Bibliography

Shinsuke Hara, Ramjee Prasad, Multicarrier Techniques for 4G Mobile Communications,
Artech House, 2003
Ramjee Prasad, OFDM for Wireless Communications Systems, Artech House, 2004
Bernard Sklar, Digital Communications: Fundamentals and Applications, 2nd edition, Prentice Hall, 2001.

Additional Material

Ahmad R. S. Bahai, Burton R. Saltzberg, Mustafa Ergen, Multi-carrier digital communications: theory and applications of OFDM, Springer, 2004
Richard D.J. van Nee, Ramjee Prasad, OFDM for wireless multimedia communications, Artech House, 2000.