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SYLLABUS Optical Fiber Communication
Optical Fiber Communication 10EC72 SYLLABUS Optical Fiber Communication Subject Code : 10EC72 IA Marks : 25 No. of Lecture Hrs/Week : 04 Exam Hours : 03 Total no. of Lecture Hrs. : 52 Exam Marks : 100 PART - A UNIT - 1 OVERVIEW OF OPTICAL FIBER COMMUNICATION: Introduction, Historical development, general system, advantages, disadvantages, and applications of optical fiber communication, optical fiber waveguides, Ray theory, cylindrical fiber (no derivations in article 2.4.4), single mode fiber, cutoff wave length, mode filed diameter. Optical Fibers: fiber materials, photonic crystal, fiber optic cables specialty fibers. 8 Hours UNIT - 2 TRANSMISSION CHARACTERISTICS OF OPTICAL FIBERS: Introduction, Attenuation, absorption, scattering losses, bending loss, dispersion, Intra modal dispersion, Inter modal dispersion. 5 Hours UNIT - 3 OPTICAL SOURCES AND DETECTORS: Introduction, LED’s, LASER diodes, Photo detectors, Photo detector noise, Response time, double hetero junction structure, Photo diodes, comparison of photo detectors. 7 Hours UNIT - 4 FIBER COUPLERS AND CONNECTORS: Introduction, fiber alignment and joint loss, single mode fiber joints, fiber splices, fiber connectors and fiber couplers. 6 Hours Dept of ECE, SJBIT Page 1 Optical Fiber Communication 10EC72 PART - B UNIT - 5 OPTICAL RECEIVER: Introduction, Optical Receiver Operation, receiver sensitivity, quantum limit, eye diagrams, coherent detection, burst mode receiver operation, Analog receivers. 6 Hours UNIT - 6 ANALOG AND DIGITAL LINKS: Analog links – Introduction, overview of analog links, CNR, multichannel transmission techniques, RF over fiber, key link parameters, Radio over fiber links, microwave photonics. Digital links – Introduction, point–to–point links, System considerations, link power budget, resistive budget, short wave length band, transmission distance for single mode fibers, Power penalties, nodal noise and chirping. -
Introduction to Optical Communication Systems
1. Introduction to Optical Communication Systems Optical Communication Systems and Networks Lecture 1: Introduction to Optical Communication Systems 2/ 52 Historical perspective • 1626: Snell dictates the laws of reflection and refraction of light • 1668: Newton studies light as a wave phenomenon – Light waves can be considered as acoustic waves • 1790: C. Chappe “invents” the optical telegraph – It consisted in a system of towers with signaling arms, where each tower acted as a repeater allowing the transmission coded messages over hundred km. – The first Optical telegraph line was put in service between Paris and Lille covering a distance of 200 km. • 1810: Fresnel sets the mathematical basis of wave propagation • 1870: Tyndall demonstrates how a light beam is guided through a falling stream of water • 1830: The optical telegraph is replaced by the electric telegraph, (b/s) until 1866, when the telephony was born • 1873: Maxwell demonstrates that light can be considered as electromagnetic waves http://en.wikipedia.org/wiki/Claude_Chappe Optical Communication Systems and Networks Lecture 1: Introduction to Optical Communication Systems 3/ 52 Historical perspective • 1800: In Spain, Betancourt builds the first span between Madrid and Aranjuez • 1844: It is published the law for the deployment of the optical telegraphy in Spain – Arms supporting 36 positions, 10º separation Alphabet containing 26 letters and 10 numbers – Spans: Madrid - Irún, 52 towers. Madrid - Cataluña through Valencia, 30 towers. Madrid - Cádiz, 59 towers. • 1855: It is published the law for the deployment of the electrical telegraphy network in Spain • 1880: Graham Bell invents the “photofone” for voice communications TRANSMITTER RECEIVER The transmitter consists of a The receiver is also a mirror made to be vibrated by parabolic reflector in which a the person’s voice, and then selenium cell is placed in its modulating the incident light focus to collect the variations beam towards the receiver. -
Wireless Networks
SUBJECT WIRELESS NETWORKS SESSION 2 WIRELESS Cellular Concepts and Designs" SESSION 2 Wireless A handheld marine radio. Part of a series on Antennas Common types[show] Components[show] Systems[hide] Antenna farm Amateur radio Cellular network Hotspot Municipal wireless network Radio Radio masts and towers Wi-Fi 1 Wireless Safety and regulation[show] Radiation sources / regions[show] Characteristics[show] Techniques[show] V T E Wireless communication is the transfer of information between two or more points that are not connected by an electrical conductor. The most common wireless technologies use radio. With radio waves distances can be short, such as a few meters for television or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice,keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Somewhat less common methods of achieving wireless communications include the use of other electromagnetic wireless technologies, such as light, magnetic, or electric fields or the use of sound. Contents [hide] 1 Introduction 2 History o 2.1 Photophone o 2.2 Early wireless work o 2.3 Radio 3 Modes o 3.1 Radio o 3.2 Free-space optical o 3.3 -
Long-Range Free-Space Optical Communication Research Challenges Dr
Long-Range Free-Space Optical Communication Research Challenges Dr. Scott A. Hamilton, MIT Lincoln Laboratory and Prof. Joseph M. Khan, Stanford University The substantial benefits of free-space optical (FSO) or laser communications (lasercom) have been well known to system designers for quite some time, c.f. [1]. The free-space channel, similar to the fiber channel, provides many benefits at optical frequencies compared to radio frequencies (RF) including extremely wide unregulated bandwidth and tightly confined beams (i.e. narrow beam divergence), both of which enable low size, weight and power (SWaP) terminals. However, significant challenges are still perceived: stochastic intensity fluctuations in a received optical signal after propagating through the atmosphere, power-starved link mode of operation, and narrow transmit beams that must be precisely pointed and tracked. Since the late 1970’s the United States [2], Europe [3] and Japan [4] have actively been developing FSO technology motivated primarily for long-haul spaceborne communication systems. While early efforts were focused on maturing FSO technology, the past decade has seen significant progress toward demonstrating the practicality of FSO for multiple applications. The first high-rate demonstration of FSO between a satellite in Geosynchronous (GEO) orbit and the ground was achieved by the US during the GeoLITE experiment in 2001. A short time later, the European Space Agency (ESA) demonstrated a 50- Mbps FSO link operating at 800-nm wavelengths between their Artemis GEO satellite and: i) another ESA spacecraft in Low-Earth orbit (LEO) in 2001 [5]; ii) a ground station located in Tenerife, Spain in 2001 [6]; and iii) an airplane flying at altitudes as low as 6,000 meters outfitted with an FSO terminal developed by France’s Astrium EADS in 2006 [7]. -
Optical Communications and Networks - Review and Evolution (OPTI 500)
Optical Communications and Networks - Review and Evolution (OPTI 500) Massoud Karbassian [email protected] Contents Optical Communications: Review Optical Communications and Photonics Why Photonics? Basic Knowledge Optical Communications Characteristics How Fibre-Optic Works? Applications of Photonics Optical Communications: System Approach Optical Sources Optical Modulators Optical Receivers Modulations Optical Networking: Review Core Networks: SONET, PON Access Networks Optical Networking: Evolution Summary 2 Optical Communications and Photonics Photonics is the science of generating, controlling, processing photons. Optical Communications is the way of interacting with photons to deliver the information. The term ‘Photonics’ first appeared in late 60’s 3 Why Photonics? Lowest Attenuation Attenuation in the optical fibre is much smaller than electrical attenuation in any cable at useful modulation frequencies Much greater distances are possible without repeaters This attenuation is independent of bit-rate Highest Bandwidth (broadband) High-speed The higher bandwidth The richer contents Upgradability Optical communication systems can be upgraded to higher bandwidth, more wavelengths by replacing only the transmitters and receivers Low Cost For fibres and maintenance 4 Fibre-Optic as a Medium Core and Cladding are glass with appropriate optical properties!!! Buffer is plastic for mechanical protection 5 How Fibre-Optic Works? Snell’s Law: n1 Sin Φ1 = n2 Sin Φ2 6 Fibre-Optics Fibre-optic cable functions -
Free Space Optics Vs Radio Frequency Wireless Communication
I.J. Information Technology and Computer Science, 2016, 9, 1-8 Published Online September 2016 in MECS (http://www.mecs-press.org/) DOI: 10.5815/ijitcs.2016.09.01 Free Space Optics Vs Radio Frequency Wireless Communication Rayan A. Alsemmeari and Sheikh Tahir Bakhsh Faculty of Computing and Information Technology, King Abdulaziz University, Saudi Arabia E-mail: {ralsemmeari, stbakhsh}@kau.edu.sa Hani Alsemmeari Institute of Public Administration Information and Technology department E-mail: [email protected] Abstract—This paper presents the free space optics (FSO) but on very low data rates. Laser technology enhanced and radio frequency (RF) wireless communication. The the use of free space optics and is now highly dependent paper explains the feature of FSO and compares it with on the laser technology. FSO in original form was the already deployed technology of RF communication in developed by the NASA and used for the military terms of data rate, efficiency, capacity and limitations. purposes in different era as fast communication link. The The data security is also discussed in the paper for technology has many commonalities with the fiber optics identification of the system to be able to use in normal technology but behaves differently in the field due to the circumstances. These systems are also discussed in a way method of transmission for both the technologies [5, 6]. that they could efficiently combine to form the single RF technology is very old technology for system with greater throughput and higher reliability. communication. It is the wireless technology for data communication. It is considered to be in use for more Index Terms—Free Space Optics, Radio frequency, than 100 years. -
Fiber Optic Cable for VOICE and DATA TRANSMISSION Delivering Solutions Fiber Optic THAT KEEP YOU CONNECTED Cable Products QUALITY
Fiber Optic Cable FOR VOICE AND DATA TRANSMISSION Delivering Solutions Fiber Optic THAT KEEP YOU CONNECTED Cable Products QUALITY General Cable is committed to developing, producing, This catalog contains in-depth and marketing products that exceed performance, information on the General Cable quality, value and safety requirements of our line of fiber optic cable for voice, customers. General Cable’s goal and objectives video and data transmission. reflect this commitment, whether it’s through our focus on customer service, continuous improvement The product and technical and manufacturing excellence demonstrated by our sections feature the latest TL9000-registered business management system, information on fiber optic cable the independent third-party certification of our products, from applications and products, or the development of new and innovative construction to detailed technical products. Our aim is to deliver superior performance from all of General Cable’s processes and to strive for and specific data. world-class quality throughout our operations. Our products are readily available through our network of authorized stocking distributors and distribution centers. ® We are dedicated to customer TIA 568 C.3 service and satisfaction – so call our team of professionally trained sales personnel to meet your application needs. Fiber Optic Cable for the 21st Century CUSTOMER SERVICE All information in this catalog is presented solely as a guide to product selection and is believed to be reliable. All printing errors are subject to General Cable is dedicated to customer service correction in subsequent releases of this catalog. and satisfaction. Call our team of professionally Although General Cable has taken precautions to ensure the accuracy of the product specifications trained sales associates at at the time of publication, the specifications of all products contained herein are subject to change without notice. -
Under Water Optical Wireless Communication
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 04 Issue: 02 | Feb -2017 www.irjet.net p-ISSN: 2395-0072 Under Water Optical Wireless Communication Smruti Goswami1, Ravi Patel2 1ME Student, Dept of EC Engineering, SVBIT, Gujarat, India 2 Assistant Professor, Dept of EC Engineering, SVBIT, Gujarat, India ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract-Underwater absorption, scattering and turbulence can be used to carry images, thus allowing viewing in tight processes will introduce attenuation and fading to light spaces. Specially designed fibers are used for a variety of propagation and then degrade the performance of underwater other applications, including sensors and fiber lasers wireless optical communications (UWOC). As power In fibers, there are two significant sections – the core and the cladding. The core is part where the light rays travel and the consumption is an important issue in under- water missions, it cladding is a similar material of slightly lower refractive index to is fundamental to minimize the intensity loss by reducing the cause total internal reflection. Usually both sections are fabricated beam divergence , data transmission in relatively high from silica (glass). The light within the fiber is then continuously turbidity waters appeals for the use of energy-efficient totally internally reflected along the waveguide. modulations and powerful channel codes at the -
Unit – 1 Overview of Optical Fiber Communication
www.getmyuni.com Optical Fiber Communication 10EC72 Unit – 1 Overview of Optical Fiber communication 1. Historical Development Fiber optics deals with study of propagation of light through transparent dielectric waveguides. The fiber optics are used for transmission of data from point to point location. Fiber optic systems currently used most extensively as the transmission line between terrestrial hardwired systems. The carrier frequencies used in conventional systems had the limitations in handling the volume and rate of the data transmission. The greater the carrier frequency larger the available bandwidth and information carrying capacity. First generation The first generation of light wave systems uses GaAs semiconductor laser and operating region was near 0.8 μm. Other specifications of this generation are as under: i) Bit rate : 45 Mb/s ii) Repeater spacing : 10 km Second generation i) Bit rate: 100 Mb/s to 1.7 Gb/s ii) Repeater spacing: 50 km iii) Operation wavelength: 1.3 μm iv) Semiconductor: In GaAsP Third generation i) Bit rate : 10 Gb/s ii) Repeater spacing: 100 km iii) Operating wavelength: 1.55 μm Fourth generation Fourth generation uses WDM technique. i) Bit rate: 10 Tb/s ii) Repeater spacing: > 10,000 km Iii) Operating wavelength: 1.45 to 1.62 μm Page 5 www.getmyuni.com Optical Fiber Communication 10EC72 Fifth generation Fifth generation uses Roman amplification technique and optical solitiors. i) Bit rate: 40 - 160 Gb/s ii) Repeater spacing: 24000 km - 35000 km iii) Operating wavelength: 1.53 to 1.57 μm Need of fiber optic communication Fiber optic communication system has emerged as most important communication system. -
Optically Controlled Microwave Devices and Circuits: Emerging Applications in Space Communications Systems
NASA Technical Memorandum 89869 1 ,' Optically Controlled Microwave Devices and Circuits: Emerging Applications in Space Communications Systems (EASA-T?l-E986S) CEIXCALLP CC h16CLLED N87-2 3900 EXBCISIVE DEVXES 1I&C ClECCIlS: EE1EEGI:IG AEELICATXOIS XI SFACE CCUIUEICIIICIS SPSlZLlS (bASA) 11 p AZLvail: 611s HC AO;/BF A01 Uoclas CSCL 09A H1/33 0079452 Kul B. Bhasin and Rainee N. Simons Lewis Research Center Cleveland, Ohio Prepared for the 1987 International Microwave Symposium cosponsored by the Brazilian Microwave Society and IEEE-MTT Rio de Janeiro, Brazil, July 27-30, 1987 OPTICALLY CONTROLLED MICROWAVE DEVICES AND CIRCUITS: EMERGING APPLICATIONS IN SPACE COMMUNICATIONS SYSTEMS Kul 6. Bhasin and Rainee N. Simons" National Aeronautics and Space Administration Lewis Research Center Cleveland, Ohio 44135 SUMMARY Optically controlled microwave devices and circuits, either directly illu- minated or interfaced by an optical fiber, have the potential to simplify signal distribution ne.tworks in high frequency space communications systems. In this paper the optical response of GaAs/GaAlAs HEMT and GaAs MESFET micro- wave devices is presented when directly illuminated by an optical beam. Mono- M e- lithic integration of optical and microwave functions on a single gallium Lo M arsenide substrate is considered to provide low power, low loss and reliable wI digital and analog optical links for control and signal distribution. The use of optically controlled microwave devices as photodetectors, to provide gain control of an amplifier, and to injection lock an oscillator in phased array antenna applications is shown. INTRODUCTION As the operating frequency and speed of solid state devices and circuits increase, their applications in advanced space communications systems will require innovative solutions to control and interconnect these devices and circuits. -
Fiber Optic Communications
FIBER OPTIC COMMUNICATIONS EE4367 Telecom. Switching & Transmission Prof. Murat Torlak Optical Fibers Fiber optics (optical fibers) are long, thin strands of very pure glass about the size of a human hair. They are arranged in bundles called optical cables and used to transmit signals over long distances. EE4367 Telecom. Switching & Transmission Prof. Murat Torlak Fiber Optic Data Transmission Systems Fiber optic data transmission systems send information over fiber by turning electronic signals into light. Light refers to more than the portion of the electromagnetic spectrum that is near to what is visible to the human eye. The electromagnetic spectrum is composed of visible and near -infrared light like that transmitted by fiber, and all other wavelengths used to transmit signals such as AM and FM radio and television. The electromagnetic spectrum. Only a very small part of it is perceived by the human eye as light. EE4367 Telecom. Switching & Transmission Prof. Murat Torlak Fiber Optics Transmission Low Attenuation Very High Bandwidth (THz) Small Size and Low Weight No Electromagnetic Interference Low Security Risk Elements of Optical Transmission Electrical-to-optical Transducers Optical Media Optical-to-electrical Transducers Digital Signal Processing, repeaters and clock recovery. EE4367 Telecom. Switching & Transmission Prof. Murat Torlak Types of Optical Fiber Multi Mode : (a) Step-index – Core and Cladding material has uniform but different refractive index. (b) Graded Index – Core material has variable index as a function of the radial distance from the center. Single Mode – The core diameter is almost equal to the wave length of the emitted light so that it propagates along a single path. -
The Future of Fiber-Optic Computer Networks
Fiber-Optic Computer Networks Paul E. Green, IBM T.J. Watson Research Center iber-optic communication is only 25 years old, but it would be difficult to exaggerate the impact it has already had on all branches of information transmission, from spans of a few meters to intercontinental distances. This strange technology, involving -of all things -the transmission of messages as pulses of light along an almost invisible thread of glass, is effectively taking over the role of guided transmission by copper and, to a modest extent, the role of unguided free-space radio and infrared transmission. If the medium itself is not strange enough, reflect on the form taken by the transmitter - the semiconductor laser diode. This device is usually no larger than a grain of sand and transmits milliwatts of infrared light - enough to send information at gigabits per second over long distances with an extremely low received bit-error rate. Yet, looking a little closer at how this supposedly revolutionary technology has been used to date, you come away with a sense that vast new unexploited opportunities await. The bandwidth is 10 orders of magnitude greater than that of phone lines (25,000 gigahertz versus 3 kilohertz), and the raw bit-error rate on the link is 10 orders of magnitude lower. Design points of are in place today (1 GHZ= io9 HZ). When you combine these numbers with the great potential for cost reductions, Fiber-optic networks it becomes clear that fiber is much more promising than anything that network architects have ever had to play with before and that a great deal more can be done have had a profound with photonic communication than is being done today.