Growing impact of optical filtering in future WDM networks

CDC ROADM design tradeoffs due to physical layer impairments in optical networks

“…In the literature, there have been several studies along the past several years that evaluate the impact of the referred PLIs, i.e. ASE noise accumulation, in-band crosstalk, filtering effects and fiber nonlinear effects, in some specific ROADM-based network scenarios, [12][13][14][15][16][17][18][19][20][21].…”

“…In [12][13][14][15], the impact of optical filtering and ASE noise in a cascade of ROADMs is assessed for several channel widths, e.g. 37.5 GHz, 50 GHz and 75 GHz, and WSS shapes.…”

“…In the referred work, the authors study the influence of several design parameters, such as the WSS shape and the signal roll-off factor, in the optical filtering impact. In a recent work, [15], the impact of optical filtering on a R&S ROADM-based network is assessed considering QPSK, 8QAM, 16QAM, and 32 QAM modulation formats signals with symbol rates faster than 60 GBaud transported on 75 GHz channels.…”

“…We would like to note that MC simulation, the method that we choose to obtain our results, is a method commonly used to study the performance of ROADMbased optical networks, e.g. [12,15,18,20], since it allows to study in a controlled environment the influence of each one of the PLIs in each of the ROADM-based scenarios considered.…”

Cross-layer static resource provisioning for dynamic traffic in flexible grid optical networks

“…A clever network control system may place latency insensitive sub-channels at the outer edges of the spectrum, in case a re-transmission is necessary. For networks catering to broadband single-carrier signals, signal processing may be used to correct the signal distortion caused by spectral overlap or over-filtering, as was suggested in [19].…”