JEP – 1082
I Semester M.E. (Electronics and Communication) Degree Examination, July 2014 (2K9 Scheme) EL-113 : OPTICAL COMMUNICATION NETWORKS Time : 3 Hours
Max. Marks : 100
Instruction : Answer any five full questions. I. Distinguish : a) Direct bandgap and indirect bandgap semiconductors. b) EDFA and SOA. c) Broadcast and select singlehop and broadcast and select multihop network. d) Laser drive and LED. II. a) Describe suitable materials used for constructing various types of fibres.
b) Deduce an expression for NA slate shells law.
c) Distinguish between bit interleaved optical TDMA and slotted optical TDM.
III. a) Explain optical transmitter and receiver with a neat diagram. b) List different types of photodiodes and explain two in detail. IV. a) Explain the following : i) Four ware mixing ii) Tunable filters iii) CHIRPING iv) DBR lasers.
b) i) Explain an STS-10 SONET frame. ii) Distinguish between SDH and SONET.
V. a) Explain the architecture of a 4 fibre BLSR and the reconfiguration under node/ line/transceiver failure. 10 b) Explain the salient features of active and passive components served to construct WDM.
JEP – 1082
VI. a) Explain the operation of a LED and a LASER diode bringing out the relationship between drive current and output power in optical. 10 b) What are optical orthogonal codes and how are they useful in OCDMA system ? 10 VII. a) Explain the operation of an optical cross connect using optical spacial switches.
b) What are soliton puber ? Derive an expression for GVD parameter and explain the effects of the same. 10 VIII. Write short notes : a) Q-switching b) Wavelength routing c) TPC-4 under water light wave system d) Homodyne and hetero junction schemes.