OC (B-TECH Electronics and Communication Engineering 7-8th)

Section-A

INTRODUCTION TO OPTICAL COMMUNICATION SYSTEMS : Electromagnetic spectrum

used for optical communication, block diagram of optical communication system. Basics of

transmission of light rays. Advantages of optical fiber communication.

Section-B

OPTICAL FIBERS: Optical fibers structures and their types, fiber characteristics : attenuation,

scattering, absorption, fiber bend loss, dispersion; fiber couplers and connectors.

Section-C

LED LIGHT SOURCE : Light emitting diode : recombination processes, the spectrum of

recombination radiation, LED characteristics, internal quantum efficiency, external quantum

efficiency, LED structure, lens coupling to fiber, behavior at high frequencies.

LASER LIGHT SOURCE : Basic principles of laser action in semi -conductors, optical gain, lasing

threshold, laser structures and characteristics, laser to fiber coupling, comparison with LED

source.

Section-D

AVALANCHE AND PIN PHOTODETECTORS: Principles of optical detection, quantum

efficiency, responsivity, general principles of PIN photodetector, intrinsic absorption, materials and

designs for PIN photodiodes, impulse and frequency response of PIN photodiodes, noise in PIN

Photodiodes, multiplication process, APD Design, APD bandwidth, APD noise.