Q. 1. What are the different types of fibers depending on refractive index profile?
What are the differences between step index and graded index fibers?
Q 2. What are single mode and multimode fibers?
What are the differences between single mode and multimode fibers?
Q. 3. What are the advantages and disadvantages of multimode fibers over single mode fibers?
Q 4 What are the advantages and disadvantages of different types of single mode and multimode fibers?
Q. 5. What is signal attenuation in an optical fiber? What is the unit of attenuation?
Q. 6. Explain various types of losses in optical fiber cable.
With the help of suitable diagrams, explain in detail basic attenuation mechanisms.
Q. 12. Write a Note on Rayleigh scattering loss in optical fibers.
Describe linear scattering losses in optical fibers with regard to (i) Rayleigh scattering (ii) Mie scattering.
Problem 1. Calculate Transmission loss factor and Rayleigh scattering coefficient for a fiber having following parameters.
Problem 2. A graded index fiber has a core with a parabolic refractive index profile which
has a diameter of . The fiber has a numerical aperture of 0.2. Estimate the number of guided modes propagating in the fiber when it is operating at a wavelength
roblem 3. Calculate the refractive indices of the core and the cladding materials of an optical fiber whose NA = 0.35 and A = 0.01.
Problem 4. Determine the cut off wavelength for a step index fiber to exhibit single mode operation when the core refractive index and radius are 1.46 and 4.5 respectively with the relative index difference being 0.25%.
Problem 5. Calculate the cut off number and number of modes supported by the step index fiber with n1 = 1.53, n2 = 1.5 and with a core radius of 50gm operating at 1550 nm.