vidhyalakshmi

UNIT I 1.Elements of fiber optic communication https://www.youtube.com/watch?v=dbHxI43z75U 2.Total internal reflection,Critical angle,numerical aperture and Acceptance angle https://www.youtube.com/watch?v=og_eXK2JoT4 https://www.youtube.com/watch?v=q37CpocWZyw 3.Types of fibers and their comparisons-singlemode,multimode,step index and graded index https://www.youtube.com/watch?v=KW3HSJthFws https://www.youtube.com/watch?v=4fJPduWQ3u4 UNIT II 1.Scattering losses and bending losses(micro and macro bending) https://www.youtube.com/watch?v=ZgeYdYPhF9A https://www.youtube.com/watch?v=ZcQsaF-sps8 2. Intermodal and intramodal dispersion https://www.youtube.com/watch?v=8oRaDSD0MDA 3.Pulse broadening in graded index fibers https://www.youtube.com/watch?v=MdpemgPmeAU 4.Mode coupling https://www.youtube.com/watch?v=-dV9o-O9Dqs Unit III 1.Surface emitting LED and Edge emitting LED https://www.youtube.com/watch?v=DBrQqy2tuq8 https://www.youtube.com/watch?v=PHkFMUHBtLU 2.PIN and Avalanche Photo dio...

  An Optical Amplifier amplifies optical signal without converting it to electronic signal They can be placed anywhere along the Optical length of the fiber They can be bidirectional Optical Multiplexing is possible They accept signals of different wavelength and provides Amplification They use Stimulated Emission like LASER .But Optical amplifiers do not have Feedback mechanism. All Optical Amplifiers have an Active medium.There is an external source called Pump to supply energy to the medium.This raises the electrons in the active medium to higher energy levels.The incoming photon from the signal(input signal which is to be amplified) will excite the electrons to lower energy level resulting in the emission of photons thereby amplifying the signal Applications of Amplifier In Line amplifier- They are used in between Transmitter and receiver to increase the distance between them Pre Amplifier-They are used before the receiver to improve its sensitivity Transmission Booster- If Opt...