Demonstration of a 280  Gbit/s free-space space-division-multiplexing communications link utilizing plane-wave spatial multiplexing

Abstract

We demonstrate a 280-Gbit/s free-space SDM communications link incorporating a set of independent tilted truncated plane-waves, each generated by a single mode fiber placed at the back-focal plane of a spherical lens. Each of the 7 tilted plane-wave channels are encoded with a 40-Gbit/s 16-QAM signal. Our approach comprises two identical linear fiber-arrays placed approximately 5 m apart. As each fiber array is placed at the back-focal-plane of a spherical lens, each fiber array is effectively placed in a conjugate image plane of the other. A channel crosstalk less than 26 dB is shown, with a bit-error-rate below the FEC threshold of 3.8 × 10−3.

Degradation of light carrying orbital angular momentum by ballistic scattering

“…Such VLC schemes could potentially be enhanced through the addition of SDM [4,7]. Orbital angular momentum (OAM) multiplexing has become the SDM technique that many have chosen to explore [2,[8][9][10][11][12][13]. Although demonstrations of OAM multiplexing in an underwater communications channel have been achieved in a controlled environment, it is important to present an understanding of the channel characteristics that would occur in a practical optical link.…”

A space division multiplexed free-space-optical communication system that can auto-locate and fully self align with a remote transceiver

“…A bespoke algorithm has been developed for the transceiver capable of self aligning the system at 200 m in an urban environment with average single mode to few mode coupling losses below 16 dB, adequate for 1 Gbps error free-transmission with widely deployed commercial transceivers. The system can also be used in low-turbulence environments to support plane-wave division multiplexing 12 , where in a data centre environment a 4-channel system with error-free transmission at 1 Gbps per channel is demonstrated.…”

Implementation and Evaluation of a Gigabit Ethernet FSO Link for 'The Last Metre and Last Mile Access Network'

“…Commercial FSO systems typically operate at Rb of ≤ 10 Gbps and can reach a range of up to 1.5 km and 30 Gbps systems are beginning to appear in the market. A number of research works demonstrating the potential for Tbps transmission using space division multiplexing and orbital angular momentum schemes have been reported [5,6], which are costly and complex.…”