Evaluation of Device Cost, Power Consumption and Network Performance in Spatially and Spectrally Flexible SDM Optical Networks

To keep pace with the rapidly increasing network traffic demand anticipated in the coming years, space-division multiplexing (SDM) has become a promising technology for overcoming the limitations of the current wavelength-division multiplexing (WDM)-based optical networks. The key advantage of SDM-based optical transmission is that it increases the network capacity by extending the available spatial dimensions. In this context, several innovative technologies have been proposed to support spatially and spectrally flexible all-optical transmission. One typical technology of this kind is called spatial and spectral super-channel (Spa & Spe SpCh) transmission. Newly designed Spa & Spe SpCh transceivers can support high-speed transmission with excellent spectral efficiency by allowing the optical carriers to be flexibly distributed in both the spatial and spectral domains without guardbands. In addition, SDM-based reconfigurable optical add/drop multiplexers (ROADMs) with varying spatial switching granularities and add/drop ports have been developed to support super-channel transmission (e.g., routing and add/drop). Moreover, ROADMs with spatial lane change support, which can further improve the routing flexibility in the network layer, have also been proposed in recent years. Different modes of implementation of the aforementioned technologies have distinct advantages and disadvantages. These technologies can be combined in various ways to support different types of SDM transmission, leading to variable network performance. In this paper, we evaluate the device cost, power consumption and network performance of SDM transmission systems based on different implementations of these technologies to serve as a reference for future research.