Impact of physical layer impairments on multi-degree CDC ROADM-based optical networks

Cost, power consumption and performance analysis in SDM ROADM architectures for uncoupled spatial channels

“…The baseline architecture is a special case of the spatial-wavelength granularity architecture, by considering 𝑀 = 1. The derived expressions of the baseline scenario have been validated and are in agreement with the expressions presented in Table 4.1 of [10].…”

“…These power leakages are the interfering terms that will impair the selected signal. In this work, we only consider the in-band crosstalk, that occurs when the interfering signals have the same nominal wavelength of the selected signal [10]. The first step to study the in-band crosstalk is to obtain the number of interfering terms in the SDM architectures.…”

A framework for analyzing in-band crosstalk accumulation in ROADM-based optical networks

“…( 1) is that this equation remains valid if a R&S architecture is considered instead of the B&S architecture considered in this work [19]. Despite the number of interfering terms 𝑁 𝑥 remaining the same, the order of the interferers would change, in particular for the R&S architecture some of the interfering terms are of second order instead of first order, as happens for the B&S architecture, which makes the R&S architecture more robust to crosstalk [19].…”

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

“…So, the total number of in-band interferers in the 1 st ROADM node is 2(R−1). When the signal is expressed in the ROADM node, the number of in-band interferers is R−2, from the ROADM inputs and more R−2 interferers from the add section, giving a total of 2(R−2) in-band interferers [30]. Note that the in-band interferers from the ROADM inputs with a R&S architecture are second order interferers, since they are blocked twice by the WSSs at the ROADM input and output.…”

“…Hence, they are statistically independent of the primary signal, and have a random phase difference and a time misalignment in relation to the primary signal. The time misalignment is modelled as a uniformly distributed random variable between zero and the symbol period, and the phase difference has also a uniform distribution within the interval [0,2π[ [30]. In each iteration of the MC simulation, a sample function of each one of the interfering signals 𝑋 𝑖,(𝑖𝑛𝑗 or 𝑎𝑑𝑑𝑗) shown in Fig.…”