Networking Benefits of Advanced DSP Techniques

We show how Digital Signal Processing (DSP) techniques can provide substantial network benefits in translucent optical networks. Given a DSP technique delivering a reduction in required OSNR, we check how many opto-electro-optic (OEO) regenerators can be removed from the topology by selectively upgrade transceivers. We study two topologies: a PanEuropean and a USNET network. Results show that, in the Pan-European network, with a reduction in requested OSNR of 1.5 dB, it is possible to remove 43% of the OEOs at the cost of improving 478 pairs of transmitters and receivers out of a total number of 1864 required before the upgrade. In the USNET network, instead, a gain of 0.9 dB makes the network fully transparent by upgrading 29 transmitters and receivers out of a total number of 581 required before the upgrade. Then, we consider the use of digital back propagation (DBP) and probabilistic shaping (PS), which are capable to provide a gain of 0.6 dB and 0.7 dB respectively. Outcomes show that, on the Pan-European network, we can remove 22% of the OEOs, improving about 240 transmitter-receiver pairs. On the USNET network, those DSP techniques can remove about 80% of the OEOs by upgrading on 23-24 transmitters and receivers.