31-07-2012, 01:08 PM
DENSE WAVELENGTH DIVISION MULTIPLEXING
DENSE WAVELENGTH .pptx (Size: 416.68 KB / Downloads: 46)
WHY DWDM
From both technical and economic perspectives, the ability to provide
potentially unlimited transmission capacity is the most obvious
advantage of DWDM technology.
What is dwdm
Dense wavelength division multiplexing (DWDM) is a
technology that uses more than eight multiplexed signals
to transmit many wavelengths of light simultaneously
over a single optical fiber .
TRANSMISSION CHALLENGES
Attenuation—decay of signal strength, or loss of light power, as the signal propagates through the fibre.
• Chromatic dispersion—spreading of light pulses as they travel down the fibre.
• Nonlinearities—cumulative effects from the interaction of light with the material through which it travels, resulting in changes in the lightwave and interactions between lightwaves .
VALUE OF DWDM IN METROPOLITAN AREA
It was first deployed on long-haul routes in a time of fiber scarcity.
Then the equipment savings made it the solution of choice for new
long-haul routes, even when ample fiber was available. Alternatives
for capacity enhancement exist, such as pulling new cable and SONET
overlays, but DWDM can do more.