Post on 02-Jan-2016
ELECTROMAGNETICS AND APPLICATIONS
Handouts:
• Info sheet (DRAFT),
• Syllabus (outline and schedule DRAFT)
• Lecture #1 slides (only this time)
Luca Daniel
L1-2
Course Outline and Motivations
• Electromagnetics:– How to transport signals and power on “guided systems”
• Applications– digital electronics: e.g. analyze transients when you send a
signal from the CPU chip to the GPU chip, or from your keyboard to your iPad
CPU
RAM
GPU A/DD/A
keyboard
iPad
L1-3
Course Outline and Motivations
• Electromagnetics:– How to transport signals and power on “guided systems”
• Applications– digital electronics: e.g. analyze transients when you send a
signal from the CPU chip to the GPU chip, or from your keyboard to your iPad
– analog and biomedical electronics: e.g. match load of RF cables bringing signal from power amplifier to MRI coil antennas to avoid reflections
CPU
RAM
GPU A/DD/A PA
L1-4
Course Outline and Motivations
• Electromagnetics:– How to transport signals and power on “guided systems”
• Applications– transport of light: e.g. fiber optics (around your globe and in
your neighborhood cable company),
– or on-chip silicon-photonics
Fiber Communications Around the Globe Prof. Watts, MIT
L1-5
Course Outline and Motivations
• Electromagnetics:– How to transport signals and power on “guided systems”
• Applications– transport of electricity in power-lines
– fluids in oil pipes, or blood in arteries and micro-fluidic channels
Prof. Han, MIT
L1-6
Course Outline and Motivations
• Electromagnetics:– How to analyze, design and couple energy to/from resonators
• Applications– e.g. in cellphone receivers: electrical (LC) resonator filters
– and MEMs resonators filters
LNA
ADC
ADC
I
Q
LO
Micron Technology, Inc
L1-7
Course Outline and Motivations
• Electromagnetics:– How to analyze, design and couple energy to/from resonators
• Applications– optical resonators (e.g. lasers)
Prof. Ippen, MIT
L1-8
Course Outline and Motivations
• Electromagnetics:– How to analyze, design and couple energy to/from resonators
• Applications– acoustical resonators (e.g. musical instruments and vocal
chords, and... your own shower “room”)
d
vocal chords
L1-9
Course Outline and Motivations
• Electromagnetics:– How to transport signals and power on “non-guided systems”
• Applications– wire antennas (e.g. inside your iPhone, or wireless router)
– aperture antennas (e.g. satellite, radar, parabola TV)
L1-10
Course Outline and Motivations
• Electromagnetics:– How to transport signals and power on “non-guided systems”
• Applications– acoustical antennas (e.g. rock concert loudspeaker)
L3-11
• Review of Fundamental Electromagnetic Laws
• Electromagnetic Waves in Media and Interfaceso Waves in homogeneous lossless and lossy media
o Power flow and energy balance (Poynting Theorem)
o Waves at interfaces
• Digital & Analog Communicationso TEM transmission lines (Telegrapher eqn.)
o Transients in digital communication wires
o Waves in RF cables
o TEM resonators
• Microwave Communicationso metallic waveguides
o microwave cavity resonators
Course Outline
L3-12
• Optical Communications• Wireless Communications
o short dipole radiation in near & far field
o receiving and transmitting antennas
o array of antennas
o wireless communication links
o aperture antennas, and understand diffraction
• Acoustics
Course Outline (continue…)
L1-13
• Course Overview and Motivations
• Maxwell Equations (review from 8.02)
– in integral form
– in differential form
– EM waves in homogenous lossless media
– EM Wave Equation
– Solution of the EM Wave equation Uniform Plane Waves (UPW)
Complex Notation (phasors)
– EM Waves in homogeneous lossy media
Today’s Outline
Next TimeNext Time
TodayToday
L1-14
Faraday’s Law:
Maxwell’s Equations (in integral form)
Electric field [volts / meter] = [V / m]
Electric displacement [amperes sec / m2] = [A s / m2]
Electric charge density [coulombs / m3] = [C / m3]
Magnetic field [amperes / meter] = [A / m]
Magnetic flux density [Tesla] = [T] = [Webers / m2] = 104 [Gauss]
Electric current density [amperes/m2] = [A / m2]
ˆS V
D nda dv Gauss’sLaws
ˆ 0 S
B nda
C S S
ˆ ˆ ˆH ds D nda J ndat
Ampere’s Law:
C S
ˆ ˆE ds B ndat
B H
D E
J E
6oIn vacuum: =1.26 10 [Henries]
12oIn vacuum: 8.854 10 [Farads /m]
E
H
L1-15
If the material properties
ε, μ and σ vary with:
Field direction
Field intensity
Position
Frequency
Time
the media is called:
Anisotropic
Non-linear
Inhomogeneous
Dispersive
Non-Stationary
Types of Media
,D E , B H J E
L1-16
Maxwell’s Equations (in differential form)
S V
D nda dv
ˆ 0 S
B nda
C S
D ˆH ds (J ) ndat
C S
ˆE ds B ndat
D
BEt
B 0
DH Jt
Stokes Theorem:
ˆV
S
F nda Fdv Gauss Divergence Theorem:
ˆ ˆA
c
F ds F nda
L1-17
2Use identity: F F F
0
Second derivative in space second derivative in time,therefore solution is any function with identical dependencieson space and time (up to a constant)
Maxwell’s Equations (in homogeneous lossless media)
0
0Faraday’s Law:
BEt
Ampere’s Law:
D D E
Gauss‘sLaw
DH Jt
B 0 B H
22
2EM Wave Equation : E E 0
t
is homogeus
[ ]
E Ht
222EYields: E E
t
ConstitutiveRelations
2
2E
tEliminate H :