Communication Theory

ESTIMATED LEARNING TIME

Scheduled learning time: 40 hours of theoretical classes and  6 hours of laboratory
Total time for learning (personal work): 100 hours.

 

PRERREQUISITES AND RECOMMENDED PREVIOUS KNOWLEDGE

Although the subject is designed to be as much self contained as possible, some previous knowledge is recommended. In particular:

• Basic statistical knowledge (probability and random variable).
• Basic knowledge about signals and systems.
  

 

GENERAL DESCRIPTION OF THE COURSE

This course presents the main theoretical concepts for analog and digital communications systems. In particular:

• The most common analog modulations are studied: amplitude, and angle (phase and frequency) modulations. The modulated signals, the required power and bandwidth, and the noise effect, are analyzed for each variant.
• The digital communication model is presented in a simplified scenario: the transmission over Gaussian channels. In this scenario, the design of every functional element in both the digital transmitter and the digital receiver is introduced.
  
• Using the quantitative measures of information proposed in the field of Information Theory, the main limits of a digital communication system are analyzed.
  

OBJECTIVES: KNOWLEDGE AND SKILLS

This subject attempts to establish the fundamental theoretical principles that are applied in the design and analysis of communication systems, both analog and digital. For this purpose, the mathematical characterization of a communication system and of the signals present in it, both transmitted signals and interfering signals such as noise, is essential. This characterization will allow the analysis of a communication system and the derivation of the theoretical principles that define the optimal design of each of its various functional elements. In particular, the following fundamental objectives can be identified:

• To introduce the statistical characterization of signals related to communication systems, information signals and, in particular, thermal noise, which is always present in the transmission of an electromagnetic signal.
• To introduce the concept of modulation in analog communication systems and to study the most common types of modulation: amplitude modulation and angle (phase and frequency) modulation.
• To form the core knowledge base for digital communications, presenting in a simplified way the concept of digital modulation, transmission over Gaussian channels, where the main element of distortion is thermal noise, and studying the basic theoretical principles to design a digital demodulator, applying the statistical principles of decision theory and the vectorial representation of signals. Finally, information theory principles are used to obtain some of the fundamental limits that can be reached in a digital communication system.
  

TEACHING MATERIAL

In the course the student will find different teaching materials:

• A book with the main theoretical contents organized in 4 chapters.
• Slides summarizing the main results.
• Videos explaining the main contents of the subject (supported by the slides).
  

Moreover, some bibliography is recommended to find additional information obout the contents of the course.

 PRACTICAL ASSIGMENTS AND ASSESSMENT ACTIVITIES

The progress of the student can be analyzed through the exercises and self-assessments questionnaires that are included in the course. For each chapter the student will find:

• Exercises with solutions.
  
• H5P questionnaires.

The exercises have a dual purpose: educational, by helping to reinforce the theoretical concepts, and self-assessment (most of the proposed exercises have been used as assessment exercises in various courses, so the student will be able to assess his or her progress).

The H5P questionnaires will allow the student a self-assessment for the main theoretical concepts introduced in the course.

Finally, three laboratory exercises are included, using the MATLAB programming language. These exercises are relatively guided and have a more didactic than evaluative objective, although some short videos are included that present the expected solutions of the realization of the exercise, which can also be used as a self-evaluation tool to assess the performance in the realization of these practical exercises.