Design and Simulation of Photonic Devices and Circuits

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Design and Simulation of PhotonicDevices and
Circuits
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Objectives

• To introduce the basic physics of photonic
  devices and apply it for the design of optical
  transmission systems and networks.
• To simulate the various photonic components and
  also to do system level simulations.
• To study different noise processes in photonic
  circuits and understand their impact on Q-factor
  or BER.
• To develop engineering rules for the photonic
  circuit design.

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Expectations

• My expectation
• Speak up.
• Course as interactive as possible.
• Your expectations ?

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Point-to-Point Optical Transmission System
Lasers Modulators Fiber Amp
DEMUX Rx
MUX
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Course Outline

• Modulation and transmission of light 6
  hours/3 lectures.
• (Device behavior models with focus on the
  terminal performance.)
• Sec. 1 Optical Modulators
• Sec. 2 Optical Fibers
• Generation, amplification and detection of light
  - 6 hours/ 4 lectures
• Sec. 3 Semiconductor lasers and LED
• Sec. 4 Amplifiers (SOA, EDFA and Raman)
• Sec. 5 Photo-detectors
  

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Course Outline

• Point-to-point, single wavelength transmission
  system (6 hours/2 lectures)
• Sec. 6 Functional Block (Tranmitter and
  Receiver) Design
• Sec. 7 Penalties due to fiber dispersion and
  amplifier noise
• Sec. 8 System design with Tx, fiber, concatenated
  amplifiers and Rx
• Eye Diagrams and Q-factor estimation
• Wavelength division multiplexed system (2
  hours/1 lecture)
• Sec. 9 Add/drop multiplexers
• Sec. 10 cross-talk in WDM system
• Linear cross-talk
• Nonlinear cross-talk due to four wave mixing
• Optical Networks (2 hours/1 lectures)
• Sec. 11 - SONET/SDH, circuit, packet and cell
  networks

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Schedule

• Jan 6 Lecture - Introduction
• Jan 13 Lecture - Sec. 1
• Jan 20 Lecture - Sec. 2
• Jan 27 - Lecture - Sec. 2
• Feb. 3 - Lecture - Sec. 3
• Feb 10 - Lecture Sec 3 4
• Feb 17 - Lecture Sec 4 5
• Feb 24 - Lecture Sec 5
• March 2 - Lecture Sec 6 7

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Schedule

• March 9 Lecture Sec 78
• March 16 Lecture Sec. 9 10
• March 23 Lecture Sec. 11
• March 30 Lecture Review

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Assessment

• Final exam 65
• Project - 35
• Each student will be assigned a project.
• The project involves
• A good research survey.
• Simulation of a photonic device or a circuit.
• Project report.

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History

• Invention of Laser and Maser in 1960s
• In 1950s, Townes and Schawlow in the US and Basov
  and Prochorov in the USSR proposed to make use of
  stimulated emission for the construction of
  coherent optical sources.
• In 1960- Maiman demonstrated the first laser.
• In 1970, Hayashi et al demonstrated GaAs
  semiconductor laser operating at room
  temperature.
• Low Loss Fibers in 1970s
• Fibers available in 1960s had losses in excess of
  1000dB/km.
• In 1970, Kapran, Keck and Maurer invented a low
  loss fiber with the loss of 20 dB/km.
• In 1979, Miya et al reported a loss of 0.2 dB/km
  near 1550 nm.
• Erbium Doped Fiber Amplifiers in 1980s.
• In 1980s, Poole et al in the UK and Desuvire in
  the US demonstrated light amplification by EDFA.
  Now it is used in all commercial long haul fiber
  optic networks.

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The Evolution of Fiber Optic Systems

• First generation operated around 850 nm. Bit rate
  45-140 Mb/s.
• GaAs-based optical souces, multimode fibers
  and silicon detectors.
• Second generation at 1300 nm. Substantial
  increase in transmission distance and bit rate
  (622 Mb/s-2.5 Gb/s).
• Both multimode and single mode fibers were
  used.

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The Evolution of Fiber Optic Systems

• Third generation systems operated around 1550 nm
  since the fiber loss _at_ 1550 nm is the lowest.
• But standard fibers have larger dispersion at
  1550 nm than at 1300 nm. Fiber manufacturers
  overcame this limitation by inventing dispersion
  shifted (DS) fibers.
• Transmission rates 2.5 Gb/s to 10 Gb/s.
• Invention of (Erbium Doped Fiber Amplifier) EDFA
  revolutionized light wave communication.
• Wavelength Division Multiplexing (WDM)
  offered a further boost in transmission capacity
• Fourth generation systems operated at 1550 nm
  with EDFA and WDM

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The Evolution of Fiber Optic Systems

• With the advent of WDM, it was realized that DS
  fibers were not suitable for long haul
  transmission because of four wave mixing among
  different channels of WDM. So, standard fiber
  (D17 ps/nm.km) or Non-zero dispersion shifted
  fiber (NZDSF) are used in current commercial
  systems. Relatively large dispersion of these
  fibers is compensated by means of dispersion
  compensating fibers.
• Large local dispersion helps to minimize four
  wave mixing penalty in WDM systems.

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Modulation Formats

• Traditionally non-return-to-zero (NRZ) format is
  used in optical communication systems.
• Recently, quasi-linear return-to-zero (RZ),
  solitons, carrier-suppressed RZ (CS-RZ) and
  differential phase shift keying (DPSK) have drawn
  considerable attention.
• Soliton is a pulse that propagates without change
  in shape. When the fiber dispersion is balanced
  by nonlinearity, solitons are formed. Solton is
  a special case of RZ format.
• NRZ requires smaller signal bandwidth as compared
  to RZ because on-off transitions occur fewer
  times.

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Contact Info

• Instructor Dr. S. Kumar
• E-mail kumars_at_mail.ece.mcmaster.ca
• Office hours Monday 230 to 500.
• Tuesday 400 to 500
• Office CRL 204
• Web page of the course www.ece.mcmaster.ca/facult
  y/kumars/Lightwave_course.htm