Reconfigurable Channel Slicing and Stitching for an Optical Signal to Enable Fragmented Bandwidth Allocation Using Nonlinear Wave Mixing and an Optical Frequency Comb

A scheme for reconfigurable channel slicing and stitching is proposed and experimentally demonstrated. By employing optical nonlinear wave mixing and a coherent frequency comb, a single channel spectrum is sliced and redistributed into fragmented frequency slots, which can be stitched together to recover the original channel at the receiver. This approach is verified through a single channel experiment with the modulation formats of quadrature phase-shift keying and 16 quadrature amplitude modulation. The system exhibits less than 1.5% error-vector-magnitude deterioration and no more than 2-dB optical signal-to-noise ratio penalty, compared to a back-to-back baseline. To demonstrate robustness of the scheme, different parameters of the channel slices are varied, such as relative phase offset, relative amplitude, and the number of slices. A 10-km transmission experiment is also conducted and the additional system penalty is negligible. This scheme is used to experimentally demonstrate fragmented channel bandwidth allocation in a dense 6-channel wavelength-division-multiplexing system. The incoming 20-Gbaud optical channel is successfully reallocated into two fragmented frequency slots and reconstructed at the receiver.