Randomly-Coupled Multi-Core Fiber Technology

Randomly-coupled multi-core fiber (MCF) technology has come to attract lots of attention because its strong applicability long-haul transmission systems. Compared with weakly-coupled MCFs independent cores, it can simultaneously realize higher spatial channel density and ultralow loss using existing ultralow-loss single-mode (SMF) core designs. The mode coupling characteristics randomly-coupled provide favorable optical properties, such as suppressed accumulation modal dispersion (MD), mode-dependent (MDL), nonlinear impairments. This article gives an overview MCF advancements. First, we describe the classification design explain what are how they designed. State-of-the-art accommodate four, seven, or 12 cores in a standard 125- $\mu \text{m}$ cladding while achieving and/or small MD, which very promising for media. Next, present methods characterize properties difference compared conventional SMF measurements. We also show low-loss low-MDL connectivity this type cabling that suppress MD. A field-deployed cable testbed is presented, confirmed after deployment. Then, amplifier technologies briefly summarized, finally, discuss performance improvements transmissions over suitable application areas.