Linear and nonlinear impairments when adding and dropping superchannels in an elastic optical network

Abstract

We investigate through simulation simultaneous linear and nonlinear impairments using a realistic reconfigurable optical add drop multiplexer (ROADM) model while considering optical filtering and in-band coherent crosstalk at each ROADM and the nonlinear interfering effects from neighbor superchannels with the QPSK or 16QAM modulation format.

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 [16][17][18][19][20][21], the in-band crosstalk effect in a cascade of ROADMs is also studied in the performance analysis, alongside the filtering effects and ASE noise, and various channels widths and WSS shapes are analyzed, as well as some specific ROADM architectures scenarios. In [16], the impact of both filtering and crosstalk is assessed considering a cascade of WSSs with different filter shapes, and 28 GBaud QPSK signals transported in 50 GHz channels.…”

“…In [19], a similar performance analysis to [18] is performed, but in this work, the influence of a frequency offset between the signal and crosstalk is also analyzed. In [20], a model for a B&S ROADM architecture with a colorless A/D structure is proposed and the impact of optical filtering, ASE noise and in-band crosstalk are studied in a cascade of ROADMs for a super channel scenario, considering 16QAM signals with 32 GBaud in 50 GHz channels. The nonlinear cross phase modulation effect is also assessed in [20].…”

“…From all the above mentioned works [12][13][14][15][16][17][18][19][20], and to the authors' understanding, the aforementioned PLIs, ASE noise, filtering effects and in-band crosstalk, have not been evaluated thoroughly and comparatively in network scenarios with several ROADMs architectures (B&S and R&S) and A/D structures (MCS and WSS-based) combinations for the 37.5 GHz channel scenario. Moreover, the referred studies [12][13][14][15][16][17][18][19][20] have not considered CDC ROADMs, only colorless or colorless and directionless ROADMs have been analyzed. Recently, in [21], we have performed an analysis of CDC ROADM-based networks, but only for the 50 GHz channel scenario and considering some simplifications in the A/D structures.…”

“…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.…”