Fiber Capacity Limits With Optimized Ring Constellations

In this letter, we calculate theoretical limits to fiber-optic transport capacity under the constraint of requiring the use of concentric multiring modulation alphabets. Subject to these conditions, we vary ring amplitude ratios and occupation probabilities to determine the capacity-optimized ring constellations. The technique used for fiber transmission calculations accurately captures all fiber nonlinear effects, with the accuracy limited by the noise and signal statistical properties only.