Grid Job Routing Algorithms - Phosphorus

Grid Job Routing Algorithms⎢ PavgN ≤ ⎢⎢⎣2huB0 ( G −1)nspSNRmin⎥⎥⎥⎦(5)A more generalized ASE noise constraint can be expressed as⎢ P ⎥− ≤ ⎢ ⎥⎣⎦Navgnsp.j( G, j 1)j=1 2huB0SNRmin∑ (7)to account for different fiber losses and different types of optical amplifiers.Chromatic Dispersion (CD)Chromatic dispersion or group velocity dispersion (GVD) has been considered for many years the most seriouslinear impairment for systems operating at bit rates from 2.5 Gbps to 10 Gbps and is causing differentfrequencies of light to travel at different speeds. This linear process causes broadening of the optical pulses,resulting in inter-symbol interference which impairs system performance. In this respect, chromatic dispersionimposes the limitation of the maximum transmission distance.Chromatic Dispersion arises for two reasons. The first is the dependence of the optical fibre’s index on theoptical wavelength (material dispersion) and the second is due to waveguide dispersion where the powerdistribution of a mode between the core and the cladding of the fiber is a function of the wavelength.In order to minimize the chromatic dispersion, various dispersion compensation techniques, which use adispersion compensation fiber (DCF), have been studied [Breuer95, Rothnie96, Hayee97], and the dispersionshifted fibers (DSF) have been deployed. It is noteworthy that the effect of GVD combined with fibernonlinearities, such as self- and cross-phase modulation (SPM/XPM) and four wave mixing (FWM), is muchmore complicated since GVD can increase or alleviate the effects of fiber nonlinearities.For this reason, for part of the simulation studies, presented in this deliverable, we handle chromatic dispersionsemi-analytically together with Self Phase Modulation (SPM) and evaluate an eye closure penalty induced fromthe combination of the two impairments.Also in another part of the simulations, the chromatic dispersion has been considered as an upper bound onthe maximum length of an M-link segment depending on the bit rate B, the chromatic dispersion D cd and themodulation format use under the following formula:dM∑ DCD , ldl