Feasibility of space-division-multiplexed transmission of IEEE 802.11 n/ac-compliant wireless MIMO signals over OM3 multimode fiber

In this paper, we have experimentally demonstrated the feasibility of space-division-multiplexed 3 × 3 multiple-input multiple-output (MIMO) transmission over a single OM3 multimode fiber (MMF) using commercial IEEE 802.11 n/ac access points. Throughput performance for different fiber length links under a range of fiber bending conditions was evaluated. To study the throughput improvement by MIMO technology, throughput performance of single-input single-output (SISO), 2 × 2 MIMO and 3 × 3 MIMO over separate SMF links was also measured for comparison. It is shown that, spatially-multiplexed MMF channel with 3 × 3 MIMO configuration could provide a significant throughput increase in comparison with SISO and 2 × 2 MIMO SMFs configurations, and present a comparable performance with 3 × 3 MIMO SMFs configuration. Meanwhile, the analyses of the impact of fiber bending indicate that, even under a tight fiber bending radius as low as 2 mm, the system performance could still keep at an acceptable level. With all fiber bending radii tested, within each 5-min measurement time, the fiber channel is found to be good enough to provide throughput greater than twice the average SISO value for more than 87.66% and 72.72% of the time, at the 2.4 and 5 GHz bands, respectively. These results together point out a very simple and cost-saving solution for future in-building DASs to distribute wireless MIMO signals using commercially-available MMF infrastructure by space division multiplexing technique, even though it may encounter tight bending conditions.