Optical Communication Question Paper Sem 7 EXTC MU Jan 2021

Q1] MCQ based Paper: 40 marks

Currently we don't have Questions of Q1

Q2]

Q2 a) Solve any Two: 5 marks each

A) A multimode step index fiber with with a core diameter of 80 µm and a relative index difference of 1.5% is operating at a wavelength of 0.85 µm. If the core refractive index 1.48, estimate:

a) the normalized frequency for the fiber

b) the number of guided modes

B) Derive the expression for pulse spreading in intermodal dispersion.

C) Compare LED and Laser Source.

Q2 b) Solve any One: 10 marks each

A) Explain any one fiber fabrication method with neat diagram.

B) For a multimode fiber following parameters are recorded.

i) LED with drive circuit has rise time of 15ns

ii) LED spectral width is 40nm

iii) Material dispersion related rise time degradation is 21 ns over 6Km link

iv) Receiver bandwidth is 25MHz

v) Modal dispersion rise time is 3.9 ns

Calculate system rise time.

Q3]

Q2 a) Solve any One out of Two: 10 marks each

A) What is Fiber bragg grating? Give its applications.

B) What is optical amplifier? Compare different types of amplifiers.

Q2 b) Solve any One out of Two: 10 marks each

A) Explain Dispersion shifted fiber and Dispersion flattened fiber.

B) Compare

i) Intermodal and Intramodal dispersion.

ii) Step Index fiber and Graded Index fiber