FIBER OPTIC
COMMUNICATIONS
Design,
Measurement, and Applications
More courses related to
optical areas are listed below.
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DATES AND LOCATIONS |
March
6 and 7, 2008 |
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April
24 and 25, 2008. |
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June
12 and 13, 2008. July
21 and 22, 2008. September
15 and 16, 2008. October
23 and 24, 2008. December
8 and 9, 2008. |
ON-SITE TRAINING: Call for more information
at 216-235-6770
Cost: $1,200.
Registration Contact: 216-235-6770
Course Description
Optical communication systems have progressed very rapidly from the research labs into commercial applications. They have already established within the transport network as-point-to point links, broadcast distribution, and interconnecting electrical nodes. Currently the progress of this technology is significantly in the diffusion of multi-wavelength extended capacity links with wavelength routing at the nodes and add-drop operations on the high-data information flowing in the optical domain. Future optical communication networks for terabit transmission rates require the use of optical routing to cope with ever increasing capacity demand due to growing internet traffic. They have been advancing to achieve enhanced personal and multimedia communications. Subcarrier optical transmission is expected to yield simple terminal equipment for many kinds of radio communication and broadcasting applications, because it offers wide-band and multicarrier transmission. As optical communication system technologies have improved, an increasing variety of applications have become technically feasible and economically attractive. The objective of this course is to provide a comprehensive overview of communication systems in the form of guidelines for designing, implementing, and testing optical systems. It offers fundamental insights as well as practical application/implementation of optical transmission systems. Both detection systems and coherent systems are described and many other techniques are presented both theoretically and experimentally in the form of numerous demonstration systems and detailed measurements, including bit-error rate, signal-to-noise ratio, crosstalk, etc. An engineering design and development are maintained through most of the sections. An attempt is made to include as much recent material as possible so that the participants are exposed to the recent advances in the field. In each section, we have provided practical problems that deal with "real-world" situations, and detailed references..No background communications prerequisites are expected for this course.
This course is provided into eight parts:
1. Overview of lightwave
2. Semiconductor laser sources and photodetectors.
3. Optical fibers, cables, and connections.
4. Fiber equipment measurements.
5. Optical components and sensors for communication applications.
6. System design and performance
7. Direct detection and coherent lightwave systems
8. Multichannel optical systems
Hung D. Nguyen, Ph.D.
Dr. Nguyen is a senior engineer for the Space Communication Division of NASA
Glenn Research Center at
This course is suitable to anyone who is already engaged in or wishing to enter the area of optical communications.
BACK .
- Be able to read the technical literature and understanding manufacturer's data sheets.
- Recognize conventional and new communications system techniques.
- Understanding the important features and design parameters of some important systems.
- Designing fundamental and advanced optical communication systems.
Overview of lightwave
Electromagnetic Spectrum
Ray theory transmission
Refraction and reflection
Critical angle, numerical aperature, refractive index difference
Acceptance angle
Snell's law
Fresnel reflection
Reflection coefficient effect of TE and TM polarization
Brewster angle
Types of polarization states
- Linear, circular, and elliptical polarizations
Jones matrix representations for
- Linear, circular, and elliptical polarization
Field representations of polarization
Which applications require polarization
Polarizing optical systems
- Linear and rotator polarizer
- Wave retarder : Quarter-wave and half-wave retarder.
Coherent state
- Perfect and partial-perfect coherence.
- Coherent time
- Coherent length
Interference states
What optical systems require coherent states
- Irradiance of coherent and incoherent waves
Diffraction
- Single and multiple slits
Interference
In class exercise
Semiconductor Laser Sources and Photodetector.
What are semiconductor sources and transmitter ?
Operating characteristics of light emitting diode (LED)
LED's structures
Types of LEDs
- Surface emitting
- Edge emitting
LED modulation and power output
Radiation pattern
Spectral width output
Tradeoff between surface-emitting and edge-emitting LED
Device performance
Device characteristics
- Modulation response, carrier lifetime, rise time
- Output power at DC and AC state
- Direct modulation of injection current.
Reliability
Applications
Semiconductor laser
Operation of semiconductor laser
Types of semiconductor laser
Double Heterostructure
Buried Heterostructure
Radiation pattern of laser
Laser specification.
- Rise and fall time.
- Threshold current.
- Spectral width.
Tradeoff comparison between double heterostructure and buried lasers
Characteristics of double and buried lasers
Principle of optical cavity resonator
- Free spectral range
- Mode spacing
- Number of longitudal modes
- Finesse
LED and laser emissions
Trade-off comparison between laser and LED
Types of laser diode
- Fabry-perot
- Distributed feedback
Modulation of laser
Pulse, intensity, and external modulation.
What are detector and receiver ?
General concepts.
- Quantum efficiency
- Conversion gain
- Rise time
- Minimum detectable signal
- Noise equivalent power
Dynamic range, responsitivity, cutoff wavelength, current gain
Linear operation, dark current, signal current, bandwidth, gain factor
Types of noise
- Thermal noise
- Dark current noise
- Shot noise
- Signal to noise ratio with/without external gain
Types of photodiode
- PIN (Positive-intrinsic negative) photodiode
- APD(Avalanche photodiode)
Characteristics of photodiode
- PIN: Silicon, Germanium, InGaAs
- APD: Silicon, Germanium, InGaAs
Speed of response
Bandwidth
Tradeoff between PIN and Avalanche detector
In class exercises
Optical Fiber, Cables, and
Connections.
Construction of fibers
Types of fibers
- Step-index fiber
- Graded index fiber
- Single-mode fiber
Fiber classifications
- Glass fiber
- Plastic-clad-silica fiber
- Plastic fiber
Fiber performances
Dimension of fibers
Advantages/benefits of fibers
Dispersions
- Intramodal dispersion: Material and waveguide.
- Intermodal dispersion: Modal effect
Limited data rate
Methods to reduce dispersions
Characteristics of step-index, graded-index, and single-mode fibers
- Delay difference, pulse broadening, bandwidth-length product
- Refractive index profile, normalized frequency
Types of attenuation
- Rayleigh scattering
- Absorption
- Bending
Multimode fibers
- Step-index type
- Graded-index type
- Structure and performance characteristics
- Refractive index profile
- Normalized frequency
- Number of guided modes.
Single-mode fibers
- Polarization-preserving fiber
- Structure and performance characteristics
- Cut-off wavelength.
- Beat length
Common fiber applications
In class exercise
Optical Cable, Connectors, and splices
Conditions of fiber cables
Maximum pulling and operating load
Maximum radius bending
Operating temperature
Mechanical resistances: Impact, crush, and flex
Main parts of cable
Core, cladding, silicone coating.
Buffer, tape, strength member, outer jacket.
Considerations of cable
Strength member
Tensile strength
Axial force
Crush resistance
Torsional/bending stress
Sharp bend
Moisture and chemical exposure
Two types of materials.
Dielectric and nondielectric cables
Cable type
Riser and plenum materials
Buffer coating
Three different buffering systems
Two types of buffer coating.
Loose buffer
Tight buffer
Simplex cable
Single optical fiber
One-way transmission
Direct connectorization
Duplex cable
Two-way transmission
Multifiber cable
Trunk transmission links
Ribbon cable
High density interconnection.
Indoor and outdoor cable
Interconnect cable
Distribution cable
Subgrouping cable
Routed to multiple locations
Arial cable
UV and weather resistance.
Armored cable
Loose tube type.
Military tactical cable
Communications and sensing cables
Aerospace cable
Cable installation
Underground installation
Aerial installation
Indoor installation
Conduit installation
Cables for different applications.
Submarine and undersea.
Industrial.
Military
Metropolitan area networks
Connectors and Splices
Introduction
Throughput loss
Return loss
Requirements of good connectors
Multifiber connectors
Mutimode and singlemode connectors
Types of connectors
Connector adapters
Types of splicing
Fusion splicing
Mechanical splicing
Tube splicing
V-groove splicing
Massive ribbon
Metal rod
Non-adhesive splice
Loss in fiber-to-fiber connection
Roughness surface
Lateral misalignment
Angular misalignment
Gap between ends
Types of loss
Insertion, excess, return, and coupling loss
Fiber Equipment Measurements.
Field measurements.
Optical source for loss measurements.
Attenuation measurement
- Mode stripper.
- Mode filter.
Fiber loss measurement.
- Cut back method.
Localization of near-end faults.
Dispersion measurement.
- Time domain method.
- Frequency domain method
Optical analyzer.
Attenuation as a function of source wavelength.
Bandwidth and dispersion.
Numerical aperture
Optical component loss measurement.
Scattering loss measurement.
Free space power measurement.
Numerical aperture measurement.
Wavelength measurement.
Spectral measurement.
Laser line-width measurement
Return loss measurement.
Back reflection.
Laser chirp measurement.
Modulation bandwidth measurement.
Bit error rate.
Optical time-domain reflectometer. (OTDR)
Link loss measurements
Reflecance and return loss measurement
Length measurement
Breaks in cable
Splice evaluation
Fault location
Measurement of coherence time and length
Components required for optical sensor
Types of optical sensors
Amplitude sensor
Phase sensor
Amplitude sensor
Variable fiber coupling
Back reflected light
Shutter structure
Microbending effect
Phase modulation
Rotational effect
Mach-Zehnder interferometer
Multimode effect
Variations of detection
Advantages of optical sensors
Two classes of sensing devices
Extrinsic sensor
Intrinsic sensor
Intensity-Modulated sensor
Grating concept
Shutter concept
Microswitching concept
Displacement sensor
Longitude concept
Differential concept
Vertical, and angular effect
Attenuation sensor
Microbend concept
Chemical in water effect
Cross-talk concept
Level effect
Reflective sensor
Single fiber
Fiber bundle
Multimode optical fiber sensors
Types of measurements
Movement
Position
Displacement
Temperature
Pressure
Single mode fiber sensors
Types of interferometer.
Mach-Zehnder
Michelson
Fabry perot
Sagnac
In class exercise
Optical Components and Sensors for
Communication Applications.
Passive and active devices.
Basic operations of couplers.
Types of loss.
- Throughput , tap, isolation , insertion, directionality, and excess loss.
Types of waveguide couplers.
- Y-junction , splitter, merging couplers.
Types of fiber couplers.
- T coupler: Grin rod and beamsplitter lenses.
- Star coupler: Transmission and reflective star
- Directional coupler.
- Wavelength selectivity.
- Wavelength division multiplexer.
- Micro-optical coupler.
- Fiber coupler.
Directional coupling waveguides.
Single mode optical 1 x N star coupler
Demultiplexer
Diffraction-grating
Grin-rod lens and interference filter
Interference filter
Bragg gratings
Mode filter
Concave grating filter
Multiplexer
Mach-Zehnder interferometer
Power splitter
Directional coupler
Optical path bending device
Facet-mirror
Refractive-effect grating
Reflective-effect grating
Filter
Interferometer wavelength filter.
Acoustic-optical tunable filter
Cross-talk
Channel separation
Wavelength isolation
Electro-optic filter
Semiconductor distributed-feedback filter
Wavelength-division multiplexer.
Optical modulators
Modulation of light: Direct and external modulation
Wavelength chirping
Polarization modulator
Absorption modulator
Amplitude modulator
Traveling wave modulator
Phase modulator
Phase-matched polarization modulator
Optical switching devices.
Directional switching coupler
Internal reflection switch
Brag-diffraction switch
Microelectromechanical systems (MEMS) switch
Phase modulator integrated with polarizer
Polarization controller.
TE - TM mode converter.
TE/TM polarization splitter.
Photoelastic waveguide and polarizer
Optical isolator
Circulator.
Semiconductor and doped-fiber amplifier
Fabry-perot amplifier
Traveling wave amplifier
Attenuator
Displacement sensor using Michelson interferometer.
Evanescent field sensor.
Gyroscope on chip and substrate.
Electric field sensor.
System Design and Performance.
System design considerations
- Short distance- LAN system.
- Medium distance- Inter-central office system.
- Long distance- Toll-office trunk system.
Influence of system choice
Bandwidth, loss budget, size and weight consideration,
system cost, reliability, distance of operations.
Launched power, fiber choice, component loss, total channel loss
Signal-to-noise ratio, system rise time, maximum bit rate
Required safety margin, receiver sensitivity.
Fiber transmission systems.
Optical/digital transmission link.
Components of fiber link.
- Transmitter
- Channel.
- Receiver.
Bandwidth limited by dispersion.
Maximum transmission distance limited by dispersion.
System power budget.
In-class exercise.
Direct Detection and Coherent Lightwave Systems.
Coherent light transmission
Components for coherent system.
Optical/Digital transmission link.
- Transmitter.
- Transmission medium.
- Receiver.
Transmitter.
- Light-emitting diode.
- Surface-emitting LEDs.
- Edge-emiting LEDs
- Laser diode.
Tranmission medium.
- Fiber-loss calculation.
- Bandwidth limited by dispersion.
- Maximum transmission distance limited by dispersion.
Types of fiber optic link.
- Direct modulation link.
- Medium distance
- Chirping problem
- Limited bandwidth
- External modulation link.
- Long-haul distance capacity.
- Low chirping problem.
- Wide bandwidth
Market demands/Advantages of fiber optic link.
Receiver design.
Modulation formats.
- Analog modulation.
- Amplitude (AM)
- Phase (PM)
- Frequency (FM)
- Digital modulation.
- Amplitude shift keying format.
- Phase shift keying format.
- Frequency shift keying format
Direct detection
- Intensity-modulation scheme.
- Analog optical receiver.
- Digital optical receiver.
Coherent detection.
- Heterodyne detection.
- Homodyne detection.
Demodulation schemes.
- ASK synchronous heterodyne scheme.
- ASK asynchronous heterodyne scheme.
- DPSK asynchronous heterodyne scheme.
- FSK asynchronous heterodyne scheme.
Comparison between direct and coherent detections.
Bit error rate and receiver sensitivity with various modulation formats.
- ASK receiver
- PSK receiver.
- FSK receiver.
Repeater system.
- Regenerator.
- Optical amplifier.
In-class exercise.
Multichannel Optical Systems.
System integration process.
- Point-to-point link.
- Point-to-multipoint: Broadcast.
- Multipoint-to-point: Network.
- Half-duplex transmission
- Full-duplex transmission.
Categories of transmission systems.
- Short, medium, and long distance.
Broadband network architecture.
- Master hub.
- Link hub
Bi-directional multiplexing transmission.
- Space division.
- Wavelength division.
- Wavelength splitter.
- Polarization division.
- Optical circulator.
Types of optical transmission.
- Time division multiplexing system.
- Wavelength division multiplexing system.
- Frequency division multiplexing system.
Multi-channel transmission.
- One direction.
- Two direction.
Multi-channels
- Electrical multiplexer.
- Optical multiplexer.
Photonic RF mixer /transmitter/receiver.
CATV system architecture
Central office systems.
- Central office network topology.
Undersea lightwave system.
Hung Nguyen, Ph.D.
Director
(216)235-6770
INFORMATION
ON REGISTRATION.
|
TIME : 8:00 – 5:00 FEES :
$1,200. 3-way of Payment: 1.Check payable to : Lightwave
Technology Corp. (Mail to: Lightwave Technology
Corp., 2. Purchase order attached : # 3. Invoice my company: Attention : Seminar Location: To be announced. |
IN-HOUSE SEMINAR INFORMATION.
Date: 2 days
Time: 8:00 - 5:00
Maximum students per training
section: 20
Fees: $ 7,800. (
Fee includes travel expense and class materials)
POLICY
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DEAD LINE REGISTRATION |
Registration by regular or electronic mail must be received at least 14
days before the first day of class (course date) |
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REFUND POLICY |
Full refund if class is cancelled. Otherwise, 20% refund less than 7 days
before the first day of class. No refund is granted the first day of class. |
Lightwave Technology
Corp. reserves the right to cancel class if there is inadequate enrollment.
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