Power division multiplexing scheme for diverse-origin, dual polarization optical communication links

We numerically simulate and experimentally demonstrate a power division multiplexing scheme for asynchronous, dual polarization signaling in a digital coherent receiver. This shared spectrum scheme supports a secondary signal with a bounded, adjustable bandwidth that can be inserted at any point along a transport fiber from a completely independent source—with distinct polarization, carrier frequency, and phase—successfully enabling recovery of both signals. Successive interference cancellation enables recovery of both signals through inversion of the demodulation chain, and the accumulated chromatic dispersion provides an estimated insertion location. We analyze how the insertion location, polarization alignment, baud rate, and power ratio impact system performance and discuss strategies to optimize this flexible scheme under practical constraints.