All-fiber Mode-division-multiplexed Recirculating-loop Transmission System with Ultralow-cost MIMO Algorithm

We experimentally demonstrate an all-fiber few-mode recirculating loop system (AF-FMRLS) with the ultralow-cost transfer-learning multi-input and multi-output (TL-MIMO) equalizers. 20 round trips were tested with the training-cost reduction up to 66.7% to 100%.