Experimental Demonstration of a Petabit per Second SDM Network Node

This paper extends a recent demonstration of a hierarchical spatial division network architecture testbed for petabit per second throughput. A spatial cross-connect is implemented to handle 1.08 Pb/s per line side. The spatial cross-connect is based on a low loss 44 × 44 MEMS switch, which enables switching up to 22 spatial channels, each carrying 202-channel, 24.5 GBaud polarization-multiplexed 64-ary quadrature amplitude modulated signals. Transmission is performed using a 22-core homogeneous multicore fiber. The demonstration includes spatial bypass and spatial add and drop scenarios as well as optical bypass and optical add and drop scenarios. The latter uses wavelength cross-connects implemented using conventional wavelength selective switches. A network scenario implementing 1 + 1 spatial multiplex section protection is also demonstrated using three 7-core joint spatial switches to protect 21 spatial channels. Finally, the use of hybrid spatial division multiplexing networks with multi-core and few-mode fibers is addressed, showing that skew between spatial channels may be the most significant obstacle to the implementation of such networks. This work concludes with an analysis of the inter-core skew introduced by the 22-core multicore fiber and its impact on a potential implementation of a hierarchical spatial division network.