Optical Fiber Communication Lecture 1 PDF

NE XXX: Optical Fiber Communication Description Components and system design for optical fiber communication. Textbook: 1. Optical fiber communication: Principles and Practices Third ED, by John M. Senior (2009) 2. FUNDAMENTALS OF PHOTONICS SECOND EDITION. BAHAA E. A. SALEH...

NE XXX: Optical Fiber Communication Description Components and system design for optical fiber communication. Textbook: 1. Optical fiber communication: Principles and Practices Third ED, by John M. Senior (2009) 2. FUNDAMENTALS OF PHOTONICS SECOND EDITION. BAHAA E. A. SALEH Boston University (2007). Location: A 3 Lecturer: Dr. Hesham Bakarman  Course Content Fibers: Step-index fibers, graded-index fibers. Fiber modes, single-mode fibers, multimode fibers. Dispersion, mode coupling, and loss mechanics. Glass materials, fiber fabrication, and characterization techniques. Sources and Transmitters: Light-emission processes in semiconductors. Light-emitting diodes (LEDs). Semiconductor lasers, (laser diodes: LDs). Modulation response. Source-fiber coupling. (Image courtesy of Artem Visual Effects.)  Course Content: continued Detectors and Receivers: Photodetectors, receivers. Receiver noise and sensitivity. Optical Amplifiers Erbium doped fiber amplifiers Semiconductor optical amplifiers Raman amplification Systems: System design: power budget and rise-time budget. (Image courtesy of C.O.R.E. Digital Picture.) Single-Wavelength Fiber-Optic Networks (FDDI, SONET) Wavelength-Division Multiplexing (WDM) Course Contents: 1. Introduction to optical fiber communications 2. Optical fiber waveguides 3. Transmission characteristics of optical fibers 4. Fiber Fabrication 5. Optical Fiber Connections, joints and couplers 6. Light sources for optical fibers 7. Optical Detectors 8. Modulation 9. Optical Networking A Short History of Optical Telecommunications Circa 2500 B.C. Earliest known glass Roman times-glass drawn into fibers Venice Decorative Flowers made of glass fibers 1609-Galileo uses optical telescope 1626-Snell formulates law of refraction 1668-Newton invents reflection telescope 1840-Samuel Morse Invents Telegraph 1841-Daniel Colladon-Light guiding demonstrated in water jet 1870-Tyndall observes light guiding in a thin water jet 1873-Maxwell electromagnetic waves 1876-Alexander Graham Bell 1876-Elisha Gray and Alexander Bell Invent Telephone 1877-First Telephone Exchange 1880-Bell invents Photophone 1888-Hertz Confirms EM waves and relation to light 1880-1920 Glass rods used for illumination 1897-Rayleigh analyzes waveguide 1899-Marconi Radio Communication 1902-Marconi invention of radio detector 1970 I. Hayashi 1910-1940 Vacuum Tubes invented and developed Semiconductor Laser 1930-Lamb experiments with silica fiber 1931-Owens-Fiberglass 1936-1940 Communication using a waveguide 1876 First commercial Telephone  A Short History- Continued 1951-Heel, Hopkins, Kapany image transmission using fiber bundles 1957-First Endoscope used in patient 1958-Goubau et. al. Experiments with the lens guide 1958-59 Kapany creates optical fiber with cladding 1960-Ted Maiman demonstrates first laser in Ruby 1960-Javan et. al. invents HeNe laser 1962-4 Groups simultaneously make first semiconductor lasers 1961-66 Kao, Snitzer et al conceive of low loss single mode fiber communications and develop theory 1970-First room temp. CW semiconductor laser-Hayashi & Panish April 1977-First fiber link with live telephone traffic- GTE Long Beach 6 Mb/s May 1977-First Bell system 45 mb/s links GaAs lasers 850nm Multimode -2dB/km loss Early 1980s-InGaAsP 1.3 µm Lasers - 0.5 dB/km, lower dispersion-Single mode Late 1980s-Single mode transmission at 1.55 µm -0.2 dB/km 1989-Erbium doped fiber amplifier 1 Q 1996-8 Channel WDM 4th Q 1996-16 Channel WDM 1Q 1998-40 Channel WDM  Bells Photophone 1880 - Photophone Receiver 1880 - Photophone Transmitter “The ordinary man…will find a little difficulty in comprehending how sunbeams are to be used. Does Prof. Bell intend to connect Boston and Cambridge…with a line of sunbeams hung on telegraph posts, and, if so, what diameter are the sunbeams to be…?…will it be necessary to insulate them against the weather…?…until (the public) sees a man going through the streets with a coil of No. 12 sunbeams on his shoulder, and suspending them from pole to pole, there will be a general feeling that there is something about Prof. Bell’s photophone which places a tremendous strain on human credulity.” New York Times Editorial, 30 August 1880  General Communication System An optical fiber communication system is similar in basic concept to any type of communication system. The function is to convey the signal from the information source over the transmission medium to the destination. Digital Optical Fiber link  Optics Optics is an old subject involving the generation, propagation & detection of light. Three major developments are responsible for innovation of optics & its application in modern technology: 1- Invention of Laser 2- Fabrication of low-loss optical Fiber 3- Development of Semiconductor Optical Device As a result, new disciplines have emerged & new terms describing them have come into use, such as: - Electro-Optics: is generally reserved for optical devices in which electrical effects play a role, such as lasers, electro-optic modulators & switches.  Photonics Optoelectronics: refers to devices & systems that are essentially electronics but involve lights, such as LED, liquid crystal displays & array photodetectors. Quantum Electronics: is used in connection with devices & systems that rely on the interaction of light with matter, such as lasers & nonlinear optical devices. Quantum Optics: Studies quantum & coherence properties of light. Lightwave Technology: describes systems & devices that are used in optical communication & signal processing. Photonics: in analogy with electronics, involves the control of photons in free space and matter.  Photonic Communications Photonics reflects the importance of the photon nature of light. Photonics & electronics clearly overlap since electrons often control the flow of photons & conversely, photons control the flow of electrons. The scope of Photonics: 1- Generation of Light (coherent & incoherent) 2- Transmission of Light (through free space, fibers, imaging systems, waveguides, … ) 3- Processing of Light Signals (modulation, switching, amplification, frequency conversion, …) 4- Detection of Light (coherent & incoherent) Photonic Communications: describes the applications of photonic technology in communication devices & systems, such as transmitters, transmission media, receivers & signal processors. Why Photonic Communications? Extremely wide bandwidth: high carrier frequency ( a wavelength of 1552.5 nm corresponds to a center frequency of 193.1 THz!) & consequently orders of magnitude increase in available transmission bandwidth & larger information capacity. Optical Fibers have small size & light weight. Optical Fibers are immune to electromagnetic interference (high voltage transmission lines, radar systems, power electronic systems, airborne systems, …) Lack of EMI cross talk between channels Availability of very low loss Fibers (0.25 to 0.3 dB/km), high performance active & passive photonic components such as tunable lasers, very sensitive photodetectors, couplers, filters, Low cost systems for data rates in excess of Gbit/s. BW demands in communication systems Type & Format Uncompressed Compressed applications Voice, digital 4 kHz voice 64 kbps 16-32 kbps telegraphy Audio 16-24 kHz 512-748 kbps 32-384 kbps (MPEG, MP3) Video conferencing 176 144 or 352 2-35.6 Mbps 64 kbps-1.544 288frames @ 10-  Mbps (H.261 30 frames/s coding) Data transfer, E- 1-10 Mbps commerce,Video entertainment Full-motion 720 480frames @ 249 Mbps 2-6Mbps (MPEG-2) broadcast video 30 frames/s HDTV 1920 1080 1.6 Gbps 19-38 Mbps frames@ 30 (MPEG-2) frames /s  Increase in Bitrate-Distance product Agrawal-Fiber Optic Communications Progress In Lightwave Communication Technology Growth of the Internet Demand Driver for High Bandwidth Communications The Internet From: www.caida.org Traffic Growth and Composition Approaches to Optical Communication  Lightwave Application Areas Laser Diode Board-to-Board Optical Rack -To-Rack N:1 D-F/F Laser Data Mux Retiming Driver Clock NE7809 µp8986 NE7809 Transmitter NE7809 Photo Detector Chip-to-Chip Optical D-F/F 1:N Preamp Data Decision DeMux PreampMain Amp Clock Clock Optical interconnects Recovery Chip to Chip (Unlikely in near future) Receiver Board to Board (>1foot eg. CPU-Memory) Subsystem-Subsystem (Optics used Low Speed) Telecommunications Long Haul (Small Market-High Performance) LANs (Large Market Lower Performance) High-Speed Analog (CATV-Remote Satellite) Optical Fiber System Why fiber? Palais-Fiber Optic Communications Optical Fiber Attenuation and Fiber Amplifier Gain Image Transmission by Fiber Bundle Optics-Hecht & Zajac Photo by American Cytoscope Makers Inc. Installed Fiber in US Global Undersea Fiber systems The Asia Africa Europe-1 (AAE-1) UUNET Example Metro network Palo Alto Fiber Optic Backbone Route Map