Fractal, Diffraction-encoded Space-Division Multiplexing for FSO with Misalignment-Robust, Roaming Transceivers

With free space optical (FSO) communication systems, information is generally transmitted to minimize diffraction. Here, we demonstrate an alternate paradigm, "diffractal space-division multiplexing" (DSDM), in which the diffraction of fractals enable a wider cone for reception to support roaming transceiver. As a result, DSDM is robust to misalignment over longer-distance links. We examine the consequence of mid-field, non-far-field propagation and the result on kernel bit error rates. The sparse and redundant encoding of information in DSDM may be relevant to other FSO acquisition, pointing, and tracking.

Effects of Mode Dispersion on Cross-phase modulation on Mode Division Multiplexed Optical Fibers

<div>The concept of mode division multiplexing also known as space division multiplexing was introduced as an alternative to combat the approaching capacity crunch in single mode fibers. Just like single mode fibers, space division multiplexed fibers will experience non-linearity at a different level and studies have shown that some linear effects can be beneficial in combating the nonlinear interference. This study aims to identify the benefits accrued when these linear effects are implemented by exploring the already existing models defined in the literature.</div>

Effects of Mode Dispersion on Cross-phase modulation on Mode Division Multiplexed Optical Fibers

<div>The concept of mode division multiplexing also known as space division multiplexing was introduced as an alternative to combat the approaching capacity crunch in single mode fibers. Just like single mode fibers, space division multiplexed fibers will experience non-linearity at a different level and studies have shown that some linear effects can be beneficial in combating the nonlinear interference. This study aims to identify the benefits accrued when these linear effects are implemented by exploring the already existing models defined in the literature.</div>

Cognitive Control-Loop for Elastic Optical Networks with Space-Division Multiplexing

This paper introduces a new solution to improve network performance by decreasing spectrum fragmentation, crosstalk interference, blocking of virtual networks, cost, and link load imbalance. These problems degrade the performance of Elastic Optical Networks with Space-Division Multiplexing. The proposed solution, called Cognitive control loop (CO-OP), is capable of identifying a set of problems and creating plans to mitigate these problems. The CO-OP comprises four functions that employ learning algorithms to identify problems and plan a series of actions to reduce or eliminate them. The results show that the CO-OP can effectively decrease up to 30% the blocking of requests and up to 50% the crosstalk occurrence compared to existing algorithms.

OAM Modes in Optical Fibers for Next Generation Space Division Multiplexing (SDM) Systems

Due to the renewed demand on data bandwidth imposed by the upcoming capacity crunch, optical communication (research and industry) community has oriented their effort to space division multiplexing (SDM) and particularly to mode division multiplexing (MDM). This is based on separate/independent and orthogonal spatial modes of optical fiber as data carriers along optical fiber. Orbital Angular Momentum (OAM) is one of the variants of MDM that showed promising features including the efficient enhancement of capacity transmission from Tbit to Pbit and substantial improvement of spectral efficiency up to hundreds (bs-1 Hz-1). In this chapter, we review the potentials of harnessing SDM as a promising solution for next generation global communications systems. We focus on different SDM approaches and we address specifically the MDM (different modes in optical fiber). Finally, we highlight the recent main works and achievements that have been conducted (in last decade) in OAM-MDM over optical fibers. We focus on main R&D activities incorporating specialty fibers that have been proposed, designed and demonstrating in order to handle appropriates OAM modes.