SRM University 2007 B.Tech Electronics and Communications Engineering Bank Optical Networks - Question Paper

10. What light source is called Lumberton?
11. Distinguish ranging from Laser and LCD Sources
12. What are the characteristics of LASER diode?
13. What are the advantages of photo detector used as light source in fiber optic communication system?
14. Define Intensity Modulation?
15. Define direct detection?
16. What are the 2 methods of modulation/demodulation techniques used today in fiber optic communication system?
17. Define Sub Carrier modulation?
18. Define Sub Carrier Multiplexing?
19. What is the application of Sub carrier Multiplexing (SCM)?
20. What is the function of preamplifier?
21. Why do we need polarization maintenance adapter (PMA) at transmitter & receiver end of the coherent optic system?
22. What does coherent system work effectively?
23. Define Receiver sensitivity?
24. What kind of optical amplifier –EDFA or SOA is used in a CATV system?


PART B

1. Draw the basic block diagram of an optical communication link and discuss the function of the different parts
2. Discuss on the principal of light transmission in a fiber
3. Draw the electric circuit of an LED & discuss the function of every component?
4. What are the various light sources available? discuss any 1 of them
5. Write short notes on i) Surface emitting LED ii) Edge emitting LED
6. Explain about Coherent optic system With block diagram

UNIT III - 1G Optical Networks
PART A

1. What does the acronym SONET stand for? What is the SONET?
2. Define SONET/SDH?
3. What are the benefits of using SONET/SDH system?
4. Define SONET Multiplexing?
5. What are the elements used in SONET/SDH system?
6. What topologies and components are used in SONET network?
7. Why a ring topology is considered reliable?
8. What are the networks used in data communication system? define the function of these networks?
9. Define MAN?
10. Draw the functional block diagram of SONET/SDH system?
11. Define STS-1 Signal?
12. Define OC-N signal?
13. Draw the STS-1 signal frame structure?
14. What is meant by saying an overhead and payload are in frame format for transmitted data?
15. Define overhead?
16. Define Transport Overhead (TOH)?
17. Define synchronous payload envelope (SPE)?
18. What is the function of TOH?
19. What is the function of SPE?
20. What is the data rate of STS-1 Signal?
21. What is the next OC signal after OC-192? What is its bit rate?
22. Calculate the data rate of STS-3 Signal (duration of the frame=125microsec)
23. Name the SONET layers
24. Define SONET physical layer?
25. What is the function of part layer?
26. What is the function of line layer?
27. Define path layer?
28. What is meant by byte interleaving multiplexer?
29. What is the function of SONET Regenerator?
30. Define Add/Drop Multiplexer?
31. Define WDM?
32. Why do we need to develop WDM fiber optic network?
33. Why is WDM the major pattern in Fiber optic network?

PART B

1. Explain the functional block diagram of the SONET/SDH Multiplexing?
2. Briefly define the functions, service of the SONET layer
3. Explain the elements of SONET/SDH infrastructure?
4. Describe how a ULSR network restores traffic
5. Describe how a BPSR network restores traffic
6. Explain about MAN with Layered Architecture
UNIT IV - Broadcast And choose Networks
PART A

1. Define Topologies?
2. Define Broadcast and choose Network?
3. Define Broadcast and choose single hop network?
4. Define Multihop network?
5. What are the characteristics of single hop network? elaborate the kinds of topologies used in data communication network?
6. Draw the block diagram of the broadcast and choose WDM network?
7. What are the topologies used in broadcast network and choose network?
8. Define an N*N star coupler?
9. What is need for passive star topology?
10. Define: Bus topology & Tree topology?
11. What is the Difference ranging from passive star topology and linear bus topology?
12. What are the characteristics used in single hop network?
13. What is the difference ranging from single hop system and multihop system?
14. Define MAC protocol?
15. What is meant by synchronization?
16. Define Slotted ALOHA?
17. Why do cable network operators are interested in new architecture(such as FTTC, FTTH)
18. Define FTTC
19. Why a CATV system is called HFC?
20. In CATV, a coaxial cable is used only for the short connection ranging from an optical receiver node & your TV set. Why is this still necessary?
21. How does access network give broadband access from the customers premises to the edge network?
22. Give a few applications of broadcast and choose technique

PART B

1. Explain the topologies of broadcast networks
2. Explain the Broadcast and choose single hop network?
3. Explain the Broadcast and choose multihop network?
4. Explain the characteristics of single hop network?
5. Explain the elements of optical access network architecture?
6. Describe Slotted ALOHA protocol?
7. Explain the future access networks
8. Explain about MAC Protocol
9. Short notes on: i) FTTC & FTTH ii) ISDN & HFC






UNIT V - Wavelength Routed Networks & Optical TDM and CDM Networks

PART A

1. What are the 2 disadvantages of broadcast & choose networks when its used in WAN
2. Which fiber optic networks belong to the 1st generation &which 1 belongs to the 2nd generation? provide E.g.
3. What are the advantages of wavelength routed network?
4. Why do we need Optical Cross Connect (OCC)?
5. How to measure the benefits of wavelength conversion?
6. Why do we need an optical layer?
7. What services does an optical layer give to the layer above?
8. Describe the optical layer service termed “establishing light path”
9. Describe the optical layer service termed “establishing virtual circuits”
10. Show the layered structure of fiber optic network , including the optical layer
11. Define OTDM?
12. Define Spread Spectrum?
13. What are spread spectrum techniques used CDMA?
14. Define Frequency Hopping Spread Spectrum?
15. Define Direct Sequence Spread Spectrum?

PART B

1. Explain OFDM
2. Explain Optical Cross Connect
3. Explain OCDMA network
4. Explain Spread Spectrum techniques?
5. Show the layered structure of fiber optic network & define their major functions

Earning:   Approval pending.