NEW
Font size
WorksheetsOFC UNIT II
Total questions: 20
Worksheet time: 10mins
Which of the following statements best explain the concept of material absorption?
A loss mechanism related to the material composition and fabrication of fiber
A transmission loss for optical fibers
Results in attenuation of transmitted light
Causes of transfer of optical power
How many mechanisms are there which causes absorption?
One
Three
Two
Four
Absorption losses due to atomic defects mainly include ___________
Radiation
Missing molecules, oxygen defects in glass
Impurities in fiber material
Interaction with other components of core
The effects of intrinsic absorption can be minimized by ___________
Ionization
Radiation
Suitable choice of core and cladding components
Melting
Optical fibers suffer radiation losses at bends or curves on their paths.
True
False
How the potential macro bending losses can be reduced in case of multimode fiber?
By designing fibers with large relative refractive ind
By maintaining direction of propagation
By reducing the bend
By operating at larger wavelengths
Sharp bends or micro bends causes significant losses in fiber.
True
False
Rayleigh scattering and Mie scattering are the types of _____________
a) Linear scattering losses
b) Non-linear scattering losses
c) Fiber bends losses
d) Splicing losses
Dominant intrinsic loss mechanism in low absorption window between ultraviolet and infrared absorption tails is ___________
a) Mie scattering
b) Rayleigh scattering
c) Stimulated Raman scattering
d) Stimulated Brillouin scattering
The scattering resulting from fiber imperfections like core-cladding RI differences, diameter fluctuations, strains, and bubbles is?
a) Rayleigh scattering
b) Mie scattering
c) Stimulated Brillouin scattering
d) Stimulated Raman scattering
What is dispersion in optical fiber communication?
a) Compression of light pulses
b) Broadening of transmitted light pulses along the channel
c) Overlapping of light pulses on compression
d) Absorption of light pulses
What does ISI stand for in optical fiber communication?
a) Invisible size interference
b) Infrared size interference
c) Inter-symbol interference
d) Inter-shape interference
3dB optical bandwidth is always ___________ the 3dB electrical bandwidth.
a) Smaller than
b) Larger than
c) Negligible than
d) Equal to
Chromatic dispersion is also called as intermodal dispersion.
a) True
b) False
In waveguide dispersion, refractive index is independent of ______________
a) Bit rate
b) Index difference
c) Velocity of medium
d) Wavelength
Intermodal dispersion occurring in a large amount in multimode step index fiber results in ____________
a) Propagation of the fiber
b) Propagating through the fiber
c) Pulse broadening at output
d) Attenuation of waves
Intermodal dispersion in multimode fibers is minimized with the use of step-index fibers.
a) True
b) False
a) True
b) False
For many applications that involve optical fiber transmission, an intensity modulation optical source is not required.
a) True
b) False
Disturbance along the fiber such as vibrations, discontinuities, connectors, splices, source/detectors coupling result in __________
a) Modal noise
b) Inter-symbol interference
c) Infrared interference
d) Pulse broadening
The modal noise can be reduced by __________
a) Decreasing width of signal longitudinal mode
b) Increasing coherence time
c) Decreasing number of longitudinal modes
d) Using fiber with large numerical aperture
