Optical Communication

Code:

F513

Acronym:

F513

Keywords
Classification	Keyword
OFICIAL	Physics

Instance: 2016/2017 - 1S

Active?	Yes
Responsible unit:	Department of Physics and Astronomy
Course/CS Responsible:	Master's Degree in Physical Engineering

Cycles of Study/Courses

Acronym	No. of Students	Study Plan	Curricular Years	Credits UCN	Credits ECTS	Contact hours	Total Time
MI:EF	8	Plano de Estudos a partir de 2007	5	-	5	-

Teaching language

Portuguese

Objectives

Knowledge of central aspects of the optical communication technology. Detailed grasp of the characteristics of propagation in optical fibres and planar guided optics, of coupling between optical waveguides and light emmitters. Knowledge of basic aspects of the coupled mode theory, and its application to the analysis of important devices (directional couplers, periodic gratings). Study electro-optic modulation of guided radiation. Knowledge of the working principles of optoelectronic devices, their structure, characteristics and applications (LEDs, diode lasers, photodetectors). Understand the basics of semiconductor and doped fibre optical amplifiers. Develop knowledge and competences suitable to develop professional activity, or pursue further studies in this area.

Learning outcomes and competences

Ability to understand the operation of microoptic and microoptoelectronic devices based on guided propagation. Device project and application competences.

 

Working method

Presencial

Program

1.Introduction Optical communication technology and optical information processing. Propagation in dielectric optical waveguides. Optical fibres, fibre-optic and integrated optic devices. Basic elements of an optical transmission system.
2. Planar optical waveguides. TE and TM guided modes of planar waveguides. Modes and total internal reflection. Dispersion equation. Mode cutoff, high and low frequency limits, number of guided modes. Normalized parameters and dispersion equation for TE and TM modes. Intermodal and intramodal dispersion. Guided power and power confinement. Radiation modes. Mode orthogonality and normalization. Expansion of a field into normal modes. Graded index profile waveguides. WKB method. MMI devices. Propagation of surface plasmons. Characterization of planar waveguides by prism coupling. Three-dimensional rectangular waveguides. Marcatili and effective index method.
3. Coupled-mode theory: directional couplers and periodic gratings. Lorentz reciprocity theorem, mode orthogonality, expansion of a field in  unperturbed waveguide eigenmodes. Coupled wave equations in modal amplitudes; coupling coefficients. Directional coupling; phase synchronism; power transfer; spectral behaviour. Tunable filter and optical switch. Directional coupling in terms of supermodes. Coupled waveguide arrays. Counter-directional coupling though a periodic grating; phase synchronism; reflection coefficient; refelctor spectral response.
4. AWG devices. AWG multiplexers/demultiplexers. Dispersion and focusing.
5. Beam Propagation Method. Computational modeling of guided wave devices. Effective index method and 2D simulations. BPM-FFT and BPM-FD. Transparent boundaries.
6. Propagation in optical fibres Propagation in step index fibres (SI). HE, EH, TE e TM modes. Dispersion equation. Modal cutoff. Normalized parameters. Dispersion and modal groups in the weakly guiding regime; LP pseudo-modes. Monomode regime. Guided power and modal confinement. Dispersion in monomode fibres. Dispersio control and US, DS e DF fibres. Modal diameter (MFD) and equivalent step index (ESI). Polarization dispersion and birefringence in optical fibres. Multimode optical fibres. Propagation in graded-index fibres (GI) according to Geometrical Optics; optical rays dispersion and profile optimization. WKB approach; dispersion and its optimization.
7. Fibre-to fibre and emmitter-to-fibre coupling. Coupling between monomode fibres, tolerances, connectors and splices; reflections. Coupling between a gaussian beam and a monomode fibre. Coupling between multimode fibres, and between an extended ammitter and a multimode fibre.
8. Optoelectronic photodetectors. Photodetection in a reverse polarized pn junction; photocurrent; model of photoconductive circuit. PIN photodetector; photocurrent, structure, efficiency, frequency response, noise. Avalanche photodetector (APD).

Mandatory literature

C.-L. Chen; Guided-Wave Optics, Wiley-Interscience, 2007
K. Okamoto; Fundamentals of Optical Waveguides, 2nd ed., Academic Press, 2006
D.L. Lee; Electromagnetic Principles of Integrated Optics, J. Wiley, 1986
J. Gowar; Optical Communication Systems, 2.nd ed., Prentice-Hall, 1993

Complementary Bibliography

G.P. Agrawal; Lightwave Technology, Components and Devices, Wiley Interscience, 2004
A. Yariv; Optical Electronics in Modern Communication, 5.th ed., Oxford U. Press, 1997
D. Marcuse; Theory of Dielectric Optical Waveguides, 2.nd ed., Academic Press, 1999
P. Bhattacharya; Semiconductor Optoelectronic Devices, Prentice-Hall, 1994
J. Singh; Optoelectronics: An Introduction to Materials and Devices, McGraw-Hill, 1996
E. Desurvire; Erbium-Doped Fiber Amplifiers, Principles and Applications, J. Wiley, 1994
G. Keiser; Optical Fiber Communications, 3.rd ed., McGraw-Hill, 2000.

Teaching methods and learning activities

Combined lecture and problem sessions.

keywords

Physical sciences > Physics > Electronics > Optoelectronics

Evaluation Type

Distributed evaluation with final exam

Assessment Components

designation	Weight (%)
Exame	100,00
Total:	100,00

Amount of time allocated to each course unit

designation	Time (hours)
Estudo autónomo	93,00
Total:	93,00

Eligibility for exams

The number of problem class sessions attended mus be at least 3/4 of the total planned.

Calculation formula of final grade

Evaluation through final exam.