This download link is referred from the post: GTU BE/B.Tech 2019 Winter Question Papers || Gujarat Technological University
Firstranker's choice
FirstRanker.com
--- Content provided by FirstRanker.com ---
Overview - Fiber Optics- What is optical Fiber
- How optical fiber is better than coaxial copper cable (i.e. advantages of using optical fibers) - more data carrying capacity (band width, band width is proportional to frequency of carrier wave), more security, least electromagnetic interference (EMI).
- Principle of working - Total Internal Reflection
- Explain Total Internal Reflection
- Composition/structure of optical fiber (discuss three layers core, clad and protective sheath along with materials i.e. glass or plastic)
- How light propagates through fiber - Explain qualitatively and show with the help of diagram.
- Define acceptance angle, acceptance cone and numerical aperture. Find their mathematical expression/relation. Give physical significance of each.
- What is A - fractional change in refractive index and express numerical aperture in terms of A.
- What is mode?
- Classification of optical fibers :
- Based on Index Profile of core -Step Index (SI) and Graded Index (GRIN). Plot the respective index profiles.
- Based on number of modes - Single Mode Fiber (SMF) and Multimode Fiber (MMF)
--- Content provided by FirstRanker.com ---
- What is V-no of fiber - V:@, where.a is core radius, A is wavelength of carrier wave; N.A. is numerical aperture of fiber. Cut off value of V is 2.405, if V<2.405, fiber is SMF and if V>2.405, fiber is MMF. Note that V-no of fiber is also known as Normalized frequency.
- Various losses through fiber - absorption, scattering, material, bending, coupling loss etc.
- Attenuation coefficient: α = (10/L)log(Pin/Pout), where L is length of fiber in km, Pin is input power launched into fiber and Pout is output power from the fiber. Units of α are dB/km.
- Joints in optical fibers - (i) Splice - permanent joint to increase the length of fiber - two types: mechanical splice n fusion splice (ii) Connector - semi-permanent/temporary joint to connect fiber with transmitter and/or receiver - can be of two types - mechanical (ferrule type) and extended beam connectors (iii) Coupler: device to split and/or combine optical signal from one port to many ports or many to one.
- Applications of optical fibers - communication system, sensors.
- Disadvantages of using optical fibers
--- Content provided by FirstRanker.com ---
--- Content provided by FirstRanker.com ---
--- Content provided by FirstRanker.com ---
This download link is referred from the post: GTU BE/B.Tech 2019 Winter Question Papers || Gujarat Technological University