Experimental Observation of Propagation Direction Dependent Performance of Single-Mode Multi-Core and Few-Mode Fiber Links

Spatial division multiplexing (SDM) systems have been extensively researched due to the potential to achieve sufficiently high throughputs to support ever increasing capacity demands [1]. Multiple types of SDM fibers, such as single-mode multi-core fibers (MCFs) and single-core few-mode fibers (FMFs), have been proposed in the literature. Hence, it is possible to envision future network scenarios where optical signals are required to propagate along different types of SDM fibers. This work addresses the particular case of hybrid MCF and FMF links. It is shown that crosstalk induced within MCF segments following FMF segments may degrade the ability of the multiple input-multiple output (MIMO) sub-system at the receiver to process the signal. However, the same does not occur as strongly when MCF segments precede FMF segments. As a consequence, the performance of such links will be conditioned by the propagation direction.