Single-Carrier 500Gb/s Unrepeatered Transmission over a Single 431km Span with Single Fiber Configuration

We demonstrate record single-carrier 500Gb/s unrepeatered transmission over a single span of 431km with single fiber configuration, using optimized high-order Raman pump, forward and backward ROPAs, and optimal modulation format while using the same single ultra low loss with large effective area fiber for both signal and pumps.