Optical Fibre & Mobile Communication (OMC)
( 12289 )
Ch 1 : Introduction to Optical Fiber ( Weightage : 26 )
S-2010
 Define the term : (4)
o Acceptance angle
o Critical angle
 State advantages and disadvantages of optical fiber cable (4)
 Explain the term intermodal dispersion in OFC (4)
 Explain the following losses : (4)
o Scattering losses
o Bending losses
 Define refractive index. Give the formula for it. Define Snell’s law with a neat diagram (4)
 Explain concept of total internal reflection in FOC (4)
 Distinguish step index with graded index fiber on the basis of : (4)
o Core radius
o Refractive index
o Light source
o Intermodal dispersion
 Draw optical analog communication system for I/P sinewave and audio signal.
Explain its operation (4)
 Draw cross sectional diagram of OFC with neat labels and explain how light
propagates through it (4)
W-2010
 How optical fiber is advantageous over co-axial cables (4)
 Explain the following terms : (4)
o Refraction
o Total Internal reflection
 Describe the occurrence of intermodal dispersion in FOC (4)
 Define the term Numerical aperture. State the effect of refractive index of core and
cladding on it (4)
 Draw the basic block diagram of optical analog communication system (4)
 What is optical fiber? Draw neat labeled cross sectional diagram of fiber optic cable (4)
 Compare single mode step index and multimode step index fiber with reference to : (4)
o Dispersion
o Core size
o Transmission rate
o Manufacturing process
 What are the different losses in optical fiber? Explain any one (4)
 The refractive index of core of fiber is 1.5 and that of cladding is 1.4. With what velocity
the light will be propagating in fiber and what should be the angle of incidence (4)
 Explain the basic block diagram of optical digital communication systems (4)
S-2011
 Define the term “Acceptance angle” and “Numerical aperture” of an optical fiber (4)
Optical Fibre & Mobile Communication (OMC)
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What is Total Internal Reflection and how light propagates through optical fiber (4)
State advantages of optical fiber over copper cable (any four) (4)
Explain in brief Absorption losses in optical fiber (4)
Draw block diagram of optical analog communication system (4)
Describe the bending losses in optical fiber (4)
Describe the mechanism of intermodal dispersion in a multimode step index fiber (4)
Describe with the aid of simple refractive index profile : (4)
o Step index fiber
o Graded index fiber
Illustrate in brief Rayleigh scattering losses (4)
W-2011
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 Define : (4)
o Total internal reflection
o Refraction
 Write applications of optical fiber (4)
 Write advantages of fiber optic communication (4)
 Write advantages of multimode graded index fiber, single mode step index fiber (4)
 Draw the block diagram of fiber optics communication system and explain any two
sections (4)
 Describe construction of fiber optic cable (4)
 List the losses in optical fiber due to scattering in foc and state bending loss (4)
 When intermodal dispersion occurs? Describe any one type (4)
 Calculate NA, OA of fiber with core index n1 = 1.61 and cladding index n2 = 1.55 (4)
 State Snell’s Law, Diffraction (4)
W-2013
 Define Refraction and Numerical Aperture (4)
 Draw the block diagram of optical communication system and write function of each
block (4)
 Describe coupling losses & bending losses in optical fibers (4)
 Write applications of optical fiber (4)
 Describe the modal dispersion loss in optical fiber (4)
 Describe the classification of optical fiber on the basis of index profile diagram (4)
 Compare optical fiber with metallic cable (4)
 State the Snell’s law and describe total internal reflection in OFC (4)
 Describe the following losses in OFC: (4)
o Scattering losses
o Wavelength loss
Optical Fibre & Mobile Communication (OMC)
( 12289 )
S-2013
 Define : (4)
o Reflection
o Numerical aperture
o Refraction
o Acceptance angle
 State applications of optical fiber (4)
 Compare step index fiber with graded index fiber (4)
 Describe optical fiber System Link budget with the help of suitable example (4)
 Calculate numerical aperture and acceptance angle for a optical fiber with core
refractive index 1.49 and cladding refractive index 1.45 (4)
 Draw block diagram of optical fiber communication system and explain significance
of each block (4)
 Describe advantages of optical fiber over metal conductor (4)
 Explain scattering loss in optical fiber (3)
 Describe total internal reflection with help of ray diagram (3)
Ch 2 : Optical Sources, Detectors, Splicing techniques, & Optical Connectors
( Weightage : 24 )
S-2010
 Draw a labeled diagram of a butt connector. Describe its construction. (4)
 Draw and describe the construction of ruby LASER (4)
 Explain the process of Avalanche multiplication in Avalanche photo diode (4)
 State the factors to be considered while selecting a splice type (4)
 Give the structure of surface emitter LED and describe its construction (4)
 Draw and describe V-groove splice (6)
W-2010
 Compare between PIN diode and avalanche photo diode (4)
 Explain the structure of LED with its working principles. Write ant two advantages (4)
 Explain the working principle of construction of Avalanche photo diode (4)
 What is meant by splicing of an optical fiber? What are the various methods of
splicing technique (4)
 What is LASER ? What are different types of LASER ? Explain (6)
 Describe different types of connectors used for optical fiber communication system (4)
S-2011
 List basic requirements the optical detectors must satisfy (4)
 Explain construction of semiconductor laser with neat diagram (4)
 List advantages associated with mechanical splicing. Explain V-groove method of
mechanical splicing (4)
Optical Fibre & Mobile Communication (OMC)
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Draw neat sketch and explain tapered sleeve connectors used for fiber optic
connection (4)
Give basic structure of avalanche photo diode. Write its working (4)
Draw neat sketch showing constructional details of surface emitting LED and explain (6)
Describe any four factors to be considered while deciding the light source in optical
fiber communication system (4)
W-2011
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 Compare LED and ILD (4)
 Draw and explain Biconical ferrule connector (6)
 List different optical sources and detectors used in fiber optic communication (4)
 Explain the working principle of LED (4)
 Draw constructional diagram of avalanche photo diode and state it’s principle (4)
 Explain the absorption of energy packets in LASER (4)
 Write APD advantages and characteristics (4)
W-2013
 Draw and describe construction of PIN photodiode (4)
 Draw and describe structure and working of Ruby laser (6)
 Compare LED and LASER (4)
 Draw and describe the basic ferrule connector (4)
 Describe the fusion splice method with diagram (4)
 Draw and describe the Biconical ferrule connector (4)
 Draw and describe the injection laser diode (4)
 State the requirements of good FOC connector (4)
S-2013
 Describe working of PIN diode with the help of constructional diagram (4)
 Compare fusion splice with V-groove splice (4)
 Describe V-groove splice with the help of suitable diagram (4)
 State types of fiber connectors. Specify applications of each type (4)
 Draw construction of Injection Laser Diode (ILD) and explain principle of light
amplification (4)
 Draw suitable diagram for Biconical Ferrule connector and explain (4)
 Compare ILD with Edge emitting LED (3)
 Draw construction of Avalanche photo diode. How carrier multiplication takes place?
Explain (3)
Optical Fibre & Mobile Communication (OMC)
( 12289 )
Ch 3 : Synchronous Optical Network ( Weightage : 10 )
S-2010
 Describe STS-1 frame structure of SONET with neat diagram (4)
 State the function of payload pointer and transport overload in SONET (4)
W-2010
 Explain the concept of optical networking (4)
S-2011
 Describe layered structure of SONET with neat diagram (4)
W-2011
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 Draw and explain SONET frames (6)
 State function of SONET layer with diagram (4)
W-2013
 Draw SONET Architecture (4)
 Describe the function of each SONET layer with diagram (6)
 Describe the need of SONET (4)
S-2013
 Describe SONET architecture with help of diagram (4)
 Describe a simple network using SONET devices (4)
 Describe SONET frame format with help of diagram (4)
Ch 4 : Introduction to Mobile Communication ( Weightage : 20 )
S-2010
 What is cell splitting? Support your answer with neat labeled diagram (4)
 Explain how the value of cluster N has a major effect on the capacity of cellular
system (4)
 Explain the landline to mobile call procedure with neat diagram (4)
 Explain the terms Roaming and call handoff (6)
 With the help of neat diagram explain the concept of cellular frequency reuse. State
mathematical formula which gives the total number of cellular channels available in
cluster (4)
W-2010
 State and explain the steps for call processing from mobile to landline (4)
 Explain the concept of cellular frequency reuse with the help of diagram (4)
Optical Fibre & Mobile Communication (OMC)
( 12289 )
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Compare between Mobile communication system and Wireless communication
system (any 4 points) (4)
What is handoff system? Give its types and explain any one (6)
What is co-channel interference? Support your answer with neat labeled diagram (4)
S-2011
 What is cell splitting and why it is required? (4)
 Explain the concept of cellular frequency reuse (4)
 Describe the term co-channel interference and adjacent channel interference with
reference to mobile communication system (4)
 Explain why and how cell splitting technique is used in cellular system (4)
 Describe the steps for call processing from mobile to mobile (6)
 What is hand off and explain in brief delayed hand off with neat sketch (4)
W-2011
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 State the cell splitting in detail (4)
 Write function of MSC, OMC (4)
 Explain hand off concept in detail (4)
 Draw the signal flow diagram for mobile call origination (4)
 Write function of VLR, HLR (4)
 Explain mobile to landline call processing (4)
 Explain frequency reuse concept with diagram (6)
 Draw the basic cellular system architecture and explain (4)
 Define co-channel interference, adjacent channel interference. How will you reduce
adjacent channel interference (4)
W-2013
 Describe evolution of cellular telephone (4)
 Describe the cell splitting concept with diagram and write its advantages (4)
 Describe the following call processing : (6)
o Mobile to land line
o Mobile to mobile
 Compare cell sectorization with cell splitting (4)
 What is co-channel interference in mobile communication ? Explain the adjacent
channel interference with diagram (4)
 Describe the Handoff process in cellular system with diagram (4)
S-2013
 What is cell? Why hexagonal shape is preferred over any other shape? (4)
Optical Fibre & Mobile Communication (OMC)
( 12289 )
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Draw 7 cell cluster of frequency reuse pattern. State the formula used to calculate the distance
between two repeating cells. State the trade off between distance and cluster size (4)
Describe mobile to mobile call procedure. State the control signals involved in it (4)
State various interferences present in cellular system. How to reduce them? (4)
What is hand off? Describe the process of hand off with help of suitable diagram (4)
Compare cell splitting with sectoring (4)
Ch 5 : G.S.M. ( Weightage : 20 )
S-2010
 State any 8 air interface parameters of GSM (4)
 State the function of following block in GSM architecture : (4)
o Mobile switching center (MSC)
o Operational support subsystem (OSS)
 Describe 3 value added services of GSM (6)
 Why GSM is preferred worldwide? (4)
W-2010
 Draw the block diagram of GSM system (4)
 State any eight air interface parameters (4)
 State the function of following block in GSM architecture (4)
o HLR
o NSS
 What are different services and features of GSM system (6)
S-2011
 Draw neat diagram showing GSM architecture (4)
 Explain typical value added services provided by GSM (any four) (4)
 State functions of following blocks in GSM (6)
o Mobile switching center
o Authentication center
o Base station controller
o Visited location register
o Home location register
o Equipment identity register
W-2011
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 What are different services provided by GSM (4)
 Draw GSM architecture diagram and write use of BTS, BSC, MS (6)
 List the algorithm names for authentication and encryption. Show diagrammatically
any one (4)
 List the specification of GSM (4)
Optical Fibre & Mobile Communication (OMC)
( 12289 )
W-2013
 Classify the GSM channels (4)
 Describe security aspect in GSM (4)
 Describe the concept of frequency reuse and roaming in GSM (4)
 Describe the authentication and encryption in GSM (4)
 Draw GSM architecture and state the role of OMC (4)
 State the function of following GSM components : (6)
o BSC
o VLR
o HLR
 Describe the use of traffic channel in GSM (4)
 List the GSM services (4)
S-2013
 Describe location updating in GSM with the help of diagram. Why is it required? (4)
 List the specifications of GSM
 How does authentication process takes place in GSM? (4)
 State GSM radio parameters ( Eight ) (4)
 Draw and explain GSM system architecture (4)
 Describe Logical control channels in GSM (4)
 Describe various GSM services (4)
 Describe how security is provided in GSM (4)