Hierarchical SDM/WDM ROADM with Any Core Access for Spatial Channel Ring Network

We demonstrate for the first time a hierarchical SDM/WDM reconfigurable optical add drop multiplexer with any-core-access functionality. This functionality is achieved by introducing a novel optical switch, core selector, together with a core selective switch.

I. Introduction

Research in the field of optical transport systems over the past 10 years has focused on exploring space as the only remaining physical dimension for signal multiplexing to accommodate the ever increasing amount of data traffic in a cost-effective manner [1]．A wide variety of fibers of new structures are being developed worldwide that support multiple guided spatial modes in a fiber. A multicore fiber (MCF) is one such space division multiplexing (SDM) fiber in which multiple single-mode cores are placed within a single fiber cladding [2]. Considerable research efforts have also been dedicated to developing mixed-layer larger-scale wavelength division multiplexing (WDM)/SDM crossconnects based on the joint switching of spatial superchannels [3] and a subsystem-modular wavelength cross-connect (WXC) architecture [4].