Optical Communication

(b) What do you understand by the multiplexing and de-multiplexing of light?What is sub-carrier multiplexing?

Define the term:

iii. Snell's law

Define the term:

ii. Numerical Aperture

Define the term:

i. Acceptance Angle 

(e) How lincar scattering does contributes to increase in BER?

(a) Explain the Optical Access Network.

(c) What are the primary features of designing of an optical source?

(b) What does the transparent windows means? Specify three peak wavelengths for the transparent window in modern optical fibers.

(a) Describe the function of the core and cladding in optical fiber. Why their refractive are indexes different.

(b) Write detail note on Synchronous optical fiber networks (SUNET).

(a) Discuss the transport networks in optical communication.

(b) Discuss the various advantages of Optical Fiber. Compare Step and Graded index fibers.

(a) Why does an optical transmission section (Amplifier) layer exist at each WDM node and not just at the amplifier node?

(b) Derive an expression for optical power generated internally to the LED.

(a) Explain the various techniques used to couple light from an LED in an optical fiber. Discuss the LED emission pattern for surface emitting LED and edge emitting LED. 

(b) What is population inversion? What is mcant by optical and electrical confinement in LASER? How is it achieved? Explain. 

(a) The light output from the GaAs is coupled into a step index fiber with a numerical aperture of 0.2, a core refractive index of 1.4 and a diameter larger than the diameter of the device. Determine the coupling efficiency into the fiber and the optical loss relative to the power emitted from the LED.

(a) Differenitate between intermodal and intramodal dispersion. Explain the concept of dispersion shifted fiber.

(b) Determine the number of modes for a multimode fiber if core radius (a=20 ), wavelength   , n₁=1.475 and n₂=1.472. How many modes will propagate if is changed to 1.3

(a) List the three major causes of attenuation in an optical fiber and explain their mechanism. How these can be minimized.

(a) Draw a block diagram of an optical communication system showing its various components. Explain in brief the function of each component.