Optical Communication — Summer 2020

Mention the advantages of Optical Communication System.

Mention the importance and significance of Optical Windows used for optical communication Purpose.

Describe Any one Method for fiber fabrication.

Define the following w.r.to Optical source and Detectors

Response Time(ii) Quantum Efficiency(iii)Sensitivity

Compare S.I. and G.I. fibers.

Describe fiber scattering Losses in brief.

Discuss intermodal dispersion in optical fibers.

Compare LED and LASER as fiber optic source.

Determine the normalized frequency at 850 nm for a step index fiber has a core radius of 20μm,core refractive index of 1.46 and cladding refractive index of 1.43. How modes propagate in this fiber at 1320 nm and 1550nm.

Describe different lensing schemes used in optical cable

Briefly Explain working of ELED(Edge emitting) as fiber sourc and its Major advantage over SLED.

Amultimode graded index fiber exhibits total pulse broadening 0.1 μsec over a distance of 10 km. Calculate(i)Optimum bandwidth on the link assuming no inter symbol interference.(ii) pulse broadening per unit length.

Derive the formula to compute loss for axial mis alignment taking place at fiber to fiber joints.

Explain in brief dark current noise in photo detector.

Describe the structure of APD (Avalanche photo detector )in brief.

Explain different techniques of splicing in brief.

Briefly describe temperature effect on Gain of APD.

Explain PIN as photo detector in brief.

Derive the equation for the power launched from LED source in to a G.I. Fiber.1

How will you measure intermodal dispersion in frequency domain?

Mention the requirement of good optical switch.

Discuss optical power loss model for a point to point link.

How will you measure chromatic dispersion?

Compare SOA and EDFPA.

Briefly explain Couplers in optical components.