Digital Signal Processing for Optical Communication Systems

Module Number: EI71067

Duration: 1 Semester

Ocurrence: Summer Semester

Language: English

Number of ECTS: 5

Staff

Professor in charge: Dr.-Ing. Tobias Fehenberger

Description of achievement and assessment methods

A written exam (90 minutes) is held at the end of the semester to assess the students’ knowledge about optical communication systems, in particular the applied methods of digital signal processing (DSP) for error-free transmission. This assessment is based on calculations, questions that require descriptive answers, and DSP programming code in a high-level language.

(Recommended) requirements

Knowledge on linear algebra and digital communication systems (modulation, signal description in time and frequency, system theory). The lecture Optical Communication Systems by Prof. Hanik is strongly recommended. Experience in Python/MATLAB is a plus.

Contents

Overview of key building blocks of optical communication systems (laser, Mach-Zehnder modulator, fiber, optical amplifier, photodiode, coherent receiver, DSP) Hands-on introduction into simulation of digital communication systems (QAM, sampling, pulse shaping, AWGN, matched filter, equalization, Monte Carlo simulations) Overview of distortions in optical communication systems (laser phase noise, frequency offset, chromatic dispersion, polarization mode dispersion, fiber nonlinearities) Digital signal processing methods for error-free operation (clock recovery, carrier phase estimation, frequency offset estimation, static and adaptive equalization).

Study goals

At the end of the module, the students will have gained insight into optical communication systems and the distortions that typically affect them, such as laser phase noise, chromatic dispersion, and polarization mode dispersion. The students will be able to analyze and assess the key digital signal processing techniques of optical receivers and will be able to implement the applied DSP methods in a high-level programming language. With their profound understanding of the topic, the students will be able to analyze and assess the performance and impact of DSP algorithms from a system-level view.

Teaching and learning methods

Teaching method: During the lectures, students are instructed in a teacher-centered style, i.e., via slide presentations that are supported by chalk-board explanations. Teaching material, including slides, and the simulation framework, are available from a web page.

The exercises are held in a student-centered way, with illustrative examples and hands-on coding exercises for the DSP parts. For the programming exercises, a framework will be provided in which students implement the required functionalities. A sample solution will be provided after each exercise. Learning method: In addition to the individual methods of the students, consolidated knowledge is aspired by repeated lessons in exercises and tutorials as well as by individual programming assignments.

Media formats

The following kinds of media are used: Presentations Lecture notes Exercises with solutions Code for simulation of an optical communication system with digital signal processing

Literature

J. Proakis, Digital communications S. Haykin, Adaptive filter theory

S. Haykin, Digital communication systems: A modern introduction

G. Agrawal, Fiber-optic communication systems

G. Agrawal, Lightwave technology systems