A. static fatigue . The process of communication using fiber optics has the following steps − Conversion of input electrical data to light signals: The data to be sent by the sender is in the form of electrical signals. Participate in the Sanfoundry Certification contest to get free Certificate of Merit. a) Greater, lesser, reduced These are the new types of optical fiber cables. SIGNAL DEGRADATION IN OPTICAL FIBER. 26) For a photo-diode with responsivity of 0.50 A/W & optical power of about 12μW, what would be the value of generated photocurrent? There are 3 main types of lasers in the market today for fiber optic transmitters – VCSELs, FP lasers and DFB lasers. c) Low current densities Following image depicts a bunch of fiber optic cables. All Rights Reserved. The Optical fiber communication processtransmits a signal in the form of light which is first converted into the light from electrical signals and transmitted, and then vice versa happens on the receiving side. The active layer of E-LED is heavily doped with ____________ The working principle of optical fiberis the transmission of the information in the form of light atoms otherwise photons. Whenever light gestures are transmitted through the optical cable, then they do not reflect the cladding & core within a sequence of zigzag bounces, sticking to a method is named as total internal reflection. a) Low The desirable properties of optical fiber sources like LASERS and diodes have been discussed in this video in detail. To practice all areas of Optical Communications, here is complete set of 1000+ Multiple Choice Questions and Answers. See our User Agreement and Privacy Policy. DH surface emitter generally give ____________ Estimate optical power coupled into fiber of DH SLED having emission area of 1.96*10-5, radiance of 40 W/rcm2, numerical aperture of 0.2 and Fresnel reflection coefficient of 0.03 at index matched fiber surface. The light propagation, along a waveguide can be described in terms of a set of guided electromagnetic waves, called as modesof the waveguide. b) 4 Answer: c Explanation: Optical fiber communication involves the use of 6 different major LED structure. Exponent in gain relation with current density. a) 5.459*10-5 d) Unaffected LED to fiber coupling is a very major issue in optical fiber communication applications employing LEDs. The spectral width determines the number of different wavelengths that are emitted from the LED or laser. View Answer, 13. In surface emitter LEDs, more advantage can be obtained by using ____________ Gate syllabus for Computer science and information Technology. a) More coupled optical power a) Zn Determine emission area of source. a. Multiple Choice Questions and Answers on Optical Fiber Communication(Part-1).Objective Questions and Answers on Optical Fiber Communication . b) 5.423*10-3 This fiber type uses a LASER to transmit the signals. There is some dispersion over long distances. It uses light as a carrier of data. Developments in LEDs are in parallel to the historical developments in fiber optic communication. b) Reduced D. coating fatigue • It is a p-n junction diode, which emits light when activated. 2. The transmitters in optical fiber links are generally light-emitting diodes (LEDs) or laser diodes. a) 2 It provides a canonical statistical description of optical signals, mostly mentioned in the literature of radio and optical communications. c) 0.3 In optical fiber communication _____ major types of LED structures are used. View Answer, 15. d) Negligible The electromagnetic energy travels through it in the form of light. d) 2.14*10-3 b) False This video describes the properties of optical fiber communication sources. The main function of a light source like LED / Laser is to change an electrical signal into the light signal. Optical components for communications principles and applications pdf, Advanced optical communication By Er. c) Cu c) High 1. All these are generally connected within one IC packag… This set of Optical Communications Multiple Choice Questions & Answers (MCQs) focuses on “LED Structures”. These signals are converted to light pulses by the transmitter circuitry using a light source. B. mechanical fatigue . An optical fiber can be understood as a dielectric waveguide, which operates at optical frequencies. d) To increase current spreading Which type of mechanical splicing exhibits the permanent bonding of prepared fiber ends with the rigid alignment of the tube? The device or a tube, if bent or if terminated to radiate energy, is called a waveguide, in general. View Answer, 6. In another scenario when it is required to communicate over long distances where more than one length of fiber cable and other supporting equipment are placed in the system. Roll no. a) BH structures Optical fiber is the most common type of channel for optical communications. The overall power conversion efficiency of electrical lens coupled LED is 0.8% and power applied 0.0375 V. Determine optical power launched into fiber. A DH surface emitter LED has an emission area diameter of 60μm. They have an entirely different concept of using light for communication. Determine the overall power conversion efficiency of lens coupled SLED having forward current of 20 mA and forward voltage of 2 V with 170 μWof optical power launched into multimode step index fiber. LED to Fiber Light Coupling. Mesa structured SLEDs are used ____________ a) Length strip geometry Optical Sources suited to Fiber Optic Communication: Light Emitting Diode (SLED, ELED, SLD) Semiconductor Laser (DFB, DBR, Vertical-Cavity Surface- Emitting Laser(VCSEL), Multi Quantum Well, In-Fiber Lasers, Fiber Ring Lasers) b) Eu View Answer, 3. The amount of radiance in planer type of LED structures is ____________ d) 0.01 • An optical Fiber is a thin, flexible, transparent Fiber that acts as a waveguide, or "light pipe", to transmit light between the two ends of the Fiber. View Answer, 14. a) 1.534*10-6 Fiber Optic Communication (2) As the carrier frequency increases, the available transmission bandwidth will increases as well. LEDs used as optical fiber transmitters emit infrared radiation at a wavelength of about 850 nm (0.85 µm). Microstructured optical fibers. 6. d) Greater, greater, increased b) 1.784*10-3 Data rates less than 20 Mbps. d) Very low • A light emitting diode (LED) is known to be one of the best optoelectronic devices out of the lot. d) 3 View Answer, 5. Now customize the name of a clipboard to store your clips. a o. Lattice constant (Δa o /α o is the misfit strain) b. d) Gain-guided structure © 2011-2020 Sanfoundry. These are the surface emitter, edge emitter, the super luminescent, the resonant cavity LED, planar LEDs and Dome LEDs. a) True 1. In optical fiber communication _____________ major types of LED structures are used. b) Less coupled optical power c) Zero Transmission Characteristics of Optical Fibers, Direct Detection Receiver Performance Considerations, here is complete set of 1000+ Multiple Choice Questions and Answers, Prev - Optical Communications Questions and Answers – LED Power and Efficiency, Next - Optical Communications Questions and Answers – LED Characteristics, Optical Communications Questions and Answers – LED Power and Efficiency, Optical Communications Questions and Answers – LED Characteristics, Engineering Chemistry I Questions and Answers, SAN – Storage Area Networks Questions & Answers, Wireless & Mobile Communications Questions & Answers, Analytical Instrumentation Questions and Answers, Electrical & Electronics Engineering Questions and Answers, Electrical Machines Questions and Answers, Engineering Physics II Questions and Answers, Analog Communications Questions and Answers, C++ Programming Examples on Data-Structures, Java Programming Examples on Data-Structures, C Programming Examples on Data-Structures, Design of Steel Structures Questions and Answers, Prestressed Concrete Structures Questions and Answers, Data Structures & Algorithms II – Questions and Answers, C# Programming Examples on Data Structures, Optical Communications Questions and Answers. In the FOC system, the light source like an LED or laser diode is used as a transmitter. e. Electron charge. Sanfoundry Global Education & Learning Series – Optical Communications. a) 1.256*10-5 You can change your ad preferences anytime. c) DH structures It is because of this reason that first and second generation optical communication systems used near parabolic index fibers. Internal absorption in DH surface emitter Burros type LEDs is ____________ Chromatic Dispersion Chromatic dispersion results from the spectral width of the emitter. For a parabolic index fiber, the pulse dispersion is reduced by a factor of about 200 in comparison to step index fiber. The fiber which is used for optical communication is waveguides made of transparent dielectrics. c) To reduce current spreading These light sources are small semiconductor devices which efficiently converts electrical signal to light signal. View Answer. Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of infrared light through an optical fiber.The light is a form of carrier wave that is modulated to carry information. This process can be explained using a diagram as shown below: Transmitter side: On the transmitter side, first if the data is analog, it is sent to a coder or converter circuit which converts the analog signal into digital pulses of 0,1,0,1…(depending on how the data is) and passed through a light source transmitter circuit… Fiber Optics: Fiber Cables Optical Fibers Single-Mode Fiber Cables The Single-Mode core is 10th the size of a human hair. b) 0.05 a) Cannot be determined Clipping is a handy way to collect important slides you want to go back to later. Light Emitting Diodes are the optical sources that made the fiber optic communication possible. 4. The cores of the fiberglass & the cladding have a special refractive index to twist inward light at a particular angle. Coupling lens used to increase efficiency. • Optical fibers are widely used in Fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication. View Answer, 2. Objective To explore design and operation of optical communication components : light emitting diode (LEDs). 178. Operating time for a 50% output reduction from an LED. View Answer, 7. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. The macroscopic bending losses show an exponential increase due to _____ in radius of curvature. Optical fiber communication technology stood out from the optical communication and has become one of the main pillars of modern communications [1]. 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Updated with latest contests, videos, internships and jobs optic transmitters –,... In use today to already 0.3 d ) 2.826 * 10-9 View Answer 3... 10-3 c ) Cu d ) 3 View Answer, 9 * 10-3 Answer. Modulated signals from the LED or laser diode is used for optical communication reached a peak in sanfoundry... A light-emitting diode ( LED ) is types of led in optical fiber communication to be ideal light sources are small semiconductor which... And Answers above, light travels due to types of led in optical fiber communication internal reflection and refractive of... Connections of power supply and modulation circuitry uses cookies to improve functionality performance! Your clips our Privacy Policy and User Agreement for details diode is used for optical communication by Er how technology... Operates at optical frequencies different major LED structure, Dome LEDs have ______________ External power efficiency effective. 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