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Seminar - An Overview of Communications Technologies


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Module 5 - SONET, WDM, DWDM and B-ISDN Technologies                                                             Slide 19 of 76 _________________                                                                                  __________

                                 Next-Generation Light Source

 

 

 

                                        Solitons 

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A light wave pulse traveling through a glass media becomes distorted and after a certain distance a repeater is required to restore the pulse to it's original shape. Solitons are solitary pulses that can propagate over a distance without appreciable deformation. Solitons are proving the key to repeaterless transoceanic optical fiber cables.

Solitary wave phenomenon was observed by a Scotsman, J. Scott Russell, in 1884. Solitons, solitary waves maintain their pulse width and spectrum over thousands of kilometers. Solitons can propagate without distortion through silicon glass. Solitary waves of larger amplitude can pass through the one of smaller amplitude while maintaining their original shapes.

The propagation velocity of solitons depends on their amplitude. The velocity increases with the amplitude. The pulse width decreases as the amplitude increases.