E D F AWhat is EDFAOrigin of EDFA (Who, When and Where)Why Erbium?How it worksBasic block diagram of EDFABlock diagram of EDFASlide 8Characteristics of EDFACharacteristics of EDFA (Contd….)Slide 11AdvantagesAdvantages (Cont…)DrawbacksCompaniesReferencesEE DD FF AA Seminar By:Geno G JamesEE-566Optical CommunicationWhat is EDFA•Type of Optical amplifier•Stands for “Erbium Doped Fiber Amplifier”•Used to boost the intensity of optical signals being carried through a fiber optic communications system •Has a fiber whose core is heavily doped with Erbium ions•Works on the concept of stimulated emission•Operates in the C band (1530-1560) and L band (1570-1610)Origin of EDFA (Who, When and Where)•Prof.David Payne and team•Published the research paper in the year 1987•At the University of Southampton, UKWhy Erbium?•Erbium has several important properties that make it an excellent choice for an optical amplifier •Erbium ions (Er3+) have quantum levels that allows them to be stimulated to emit in the 1540nm band, which is the band that has the least power loss in most silica-based fiber. •Erbium's quantum levels also allow it to be excited by a signal at either 980nm or 1480nm, both of which silica-based fiber can carry without great lossesHow it works•Energy band of ErbiumDemoBasic block diagram of EDFABlock diagram of EDFA•Copropogating Pump EDFABlock diagram of EDFA•Counterpropogating Pump EDFACharacteristics of EDFA•Gain and NoiseCharacteristics of EDFA (Contd….)Characteristics of EDFA (Contd….)Advantages•Commercially available in C-band & L-band•Insensitivity to light polarization state•High gain•Low noise figure: 4.5 dB to 6dB•No distortion at high bit rates•Simultaneous amplification of wavelength division multiplexed signals•Immunity to cross talk among wavelength multiplexed channelsAdvantages (Cont…)•Do not require high speed electronics•Independent of bit rate (Bit rate transparency)Drawbacks•Pump laser necessary•Need to use a gain equalizer for multistage amplification•Difficult to integrate with other components•Dropping channels can give rise to errors in surviving channelsCompanies•You name them………. and they are thereReferences•DWDM Fundamentals, Components and Applications by Jean-Pierre Laude•Fiber Optic Communication Technology by Djafar K.Mynbaev and Lowell L.Scheiner•www.soton.ac.uk •www.photon-x.net/tech/edfa.htm •www.webopedia.com• www.mse.vt.eduThank