Elektromagnetisme
(
IR-ELEC-6218
)
2009 - 2010
Electromagnetism
A. BAREL (email: Alain.Barel@vub.ac.be)
Subject area work unit Electricity
Programme Bachelor of Applied Sciences and Engineering
Advanced
6 study points in the 2nd semester and
170 hours of study time
42 contacthours Lecture ( A. BAREL )
30 contacthours Seminar, Exercises or Practicals ( A. BAREL )
Competences
-aims and objectives :
Tranfer to the student of knowledge and 'vaardigheden' =abilities of advanced electromagnetic problems. This course fits into a whole programme of electromagnetism that starts in the first year (candidature), continues in the second year and terminates in the third year, which is the first of the speciality 'Electrotechnics'. For the speciality 'Electrotechnics', the course is followed by the compulsory course 'Microwaves and UHF techniques' and by the optional course 'Numerical methods for Electromagnetics'. The theoretical knowledge is brought to the students by solving analytically some propagation problems of electromagnetism. The emphasis is layed on the generic character of the choosen solution to prepare the student to an active type of assimilisation of the matter. This means clearly that the student must be able to solve these problems by himself. Abilities are brought to the student in the domain of the high-frequency techniques to be shure he will be able of handling transmission line technologies. These are: the Smith-Chart, the Time Domain Reflectometry (TDR), the technique of localizing defaults and missmatches by interpretation of standing waves, Stub Matching techniques.
-exam requirements :
Written examination covering tutorials and laboratory work: The student must be able to solve exercices of the same difficulty as those given during the tutorials. They must also be able to exploitand interprete the data obtained by measurements done at the laboratory. The students may consult all notes and textbooks they want. Oral examination covering theory: The students are expected to solve the Helmholtz equation to establisch the distribution of the electrical field in all studied configurations (cases or geometries) studied during the lectures. The sudent must be able to comment the obtained electrical field, more specially the spacial distribution, the orientation of the vector and the presence of modes and their consequences on the propagation properties. Te student may not consult any notes or textbooks except some short list of the following formulas: gradiant, divergence, rotation(=curl) and Laplacian in cylinder and spherical coordinates.
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Previous knowledge
Knowledge of the complex calculus.
Knowledge of the Maxwell equations and of the continuity conditions of the fields.
Knowledge of the solving techniques of second order partial differential equations.
Knowledge of the Laplace and Fourier transformations.
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Content
Starting from the very general Maxwell equations, a bridge is layed toward the differential equations that govern the behaviour of the electrical field in free space. This simple differential equation is subsequently solved by use of simple mathematical functions in different cases or geometries. These cases cover all the real engineering problems or are fair approximations of them. This include the propagation of electromagnetical waves in free space or in waveguides like the coaxial cable, the rectangular metal waveguide en dielectric guides. The dissipative behaviour of the electrical field is also studied in the case of Skin-effect in conductors. A lot of time and efforts are spent to the theory and the practical applications of the transmission lines. This includes a whole collection of techniques that are illustrated in the tutorials and in the laboratory work. Let us mention: the S-parameters, the reflection coefficients, the VSWR, the reflectometry and the singe- and double-stub matching techniques. Finally some energetic concepts of the propagation of the electromagnetic fields in the free space, like the vector of Poynting permit to lay down the basics of the theory of the antennas and to calculate the power balance of a radio propagation.
The course is splitted up in the following items and hours.
Lectures (30 uur):
Wave propagation of E and Complex representation 1
Helmholtz equation and critical frequency 2
Plane waves and polarisation 1
Skin effect 3
Coaxial cable 2
Differential equation of a transmissionline 2
( Smith Chart, Stub Matching)
S parameters and wave formalism 1
TDR (Time Domain Reflectometry) 1
Standing Waves - VSWR 1
Bergeron 2
Parallel plane metalic waveguides 1
Rectangular metalic waveguides 2
Dielectric waveguides 3
Vector and theorem of Poynting 1
Dipole of Hertz (Retarded Biot-Savart) 2
Radiation resistance, power and gain, Resonating dipole 2
Helmholtz - Kirchoff diffractionintegral, Principle of Huygens 1
Fraunhoferdiffraction in apertures and grids 2
Tutorial (15 uur):
Calculus of the AC resistance of cylindric conductors at 50 Hz(mains), 1 MHz(AM radio), 100 MHz(FM radio), 1GHz (GSM) and 10 GHz (Radar). 2
TDR 3
Standing waves 1
Single stub matching 4
Double stub matching 3
Bergeron 2
Laboratory work (15 uur):
TDR 3
Standing waves / Reflection factor 3
Coupler / Hornantenna 3
Cut-off waveguide, attenuation and fase 3
Dipole antenna 3
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Study Material
Dutch notes 'Elektromagnetisme' edited by the 'Dienst Uitgaven VUB'.
C.T.A. JOHNK, Engineering Electromagnetic Field and Waves, Wiley 1975, 1986
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Mode Assessment
1st session: Laboratory work 10%
Written examination of 4 hours covering tutorials and laboratory work 50% (open book)
Oral examination covering theory 40% (a special formularium may be used)
2de session: idem
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Additional Information
Because this course is only given in flemish, it is stronly adised to the english speaking students to learn flemish.
Nevertheless english reference notes are available.
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