eahaidar said:
Thank you my friend do u have any papers concerning FWM that would be great also thank you
Eahaidar,
You have asked about “FWM”. This abbreviation might stand for “Four Wave Mixing”, or something else.
But I guess you meant “FWHM”. This abbreviation stands for “full width at half maximum” and appears in
Section Two of the paper “Stimulated Brillouin Scattering: An Overview of Measurements, System Impairments, and Applications” referenced above.
If my guess is correct, you need to learn exactly what the term means, because it is commonly used in many areas of science. One place to begin is Wikipedia:
“Full width at half maximum (FWHM) is an expression of the extent of a function, given by the difference between the two extreme values of the independent variable at which the dependent variable is equal to half of its maximum value.
FWHM is applied to such phenomena as the duration of pulse waveforms and the spectral width of sources used for optical communications...”
http://en.wikipedia.org/wiki/Full_width_at_half_maximum
These two sites also explain “FWHM”:
http://www.noao.edu/wiyn/images/fwhm.html
http://ned.ipac.caltech.edu/level5/Leo/Stats2_3.html
Finally, here’s another paper that gives an excellent overview of your topic:
"NONLINEAR SCATTERING EFFECTS IN OPTICAL FIBERS
S. P. Singh, R. Gangwar, and N. Singh
Department of Electronics and Communication
University of Allahabad
Allahabad-211002, India
Abstract—The nonlinear scattering effects in optical fiber occur due
to inelastic-scattering of a photon to a lower energy photon. This
paper describes stimulated Brillouin scattering and stimulated Raman
scattering processes. Their thresholds, reduction in power penalty and
applications along with comparative study of these effects are also
presented."
http://jpier.org/PIER/pier74/23.07051102.Singh.GS.pdf
Cheers, Bobbywhy