Punjab Engineering College 2005 B.Tech Fibre Optics Communication - Question Paper

EC 422 B Tech eighth Sem May 2005

FIBRE OPTICS COMMMUNICATION

Note: part A is compulsory. Attempt any 4 ques. every carrying five marks from part B and any 2 every carrying 10 marks from part C.

part A (10 x two = 20)
1.

1. How is light guided through optical fibres?
2. elaborate optical fibres immune to?
3. How is characteristic value for the fibre and the attenuation of optical fibres related?
4. What is dispersion?
5. List the components of optical fibre communication
6. What is a step-index multimode fibre?
7. Which kind of fibre has the highest modal dispersion?
8. How is light emission from an LED modulated?
9. What is a pin photodiode?
10. describe fibre refractive index.

part B (4 x five = 20)

2. explain the Electromagnetic mode theory for optical propagation.

3. discuss the measurement procedure for Fibre attenuation and fibre diameter.

4. explain the modulation of laser diodes.

5. define the principles of optical detection.

6. discuss the optical transmitter circuit.

part C (2 x 10 = 20)

7. define with examples the different kinds of losses in optical fibre transmission.

8. explain the LED structure, characteristics, efficiency and modulation process.

9. Write notes on:
(a) Photodiode materials
(b) Optical receiver circuit

Earning:   Approval pending.