11-02-2013, 04:43 PM
Evolution of Optical Fiber Transmission Systems
Evolution of Optical Fiber.ppt (Size: 7.38 MB / Downloads: 228)
Faculty Development Program
Introduction to Transmission Systems
Evolution of transmission systems
PDH
SDH
WDM
DWDM
All Optical Networking
Evolution of Transmission Media
Copper Cable
Co-axial Cable
Wireless - Microwave, Satellite
Copper/Coaxial Cable with PCM
Optical Fiber Cable
WHAT ARE OPTICAL FIBERS ?
Optical Fibers are thins long (km) strands of ultra pure glass (silica) or plastic that can to transmit light from one end to another without much attenuation or loss.
The glass used to make Optical Fibers is so pure that if the Pacific Ocean was filled with this glass then we would be able to see the ocean bottom form the surface….!!!!
This is to be believed as repeater distances on long haul routes for optical fibers vary from 50 to 150 km.
Working of Optical fibers
The light source (LASER) at the transmitting (Tx) end is modulated by the electrical signal and this modulated light energy is fed into the Optical Fiber.
At the receiving end (Rx) this light energy is made incident on photo-sensors which convert this light signal back to electrical signal.