All-Optical Signal Processing Techniques for Flexible Networks

1. Optical signal processing could add tunable and reconfigurable functions in physical layer that can enhance network flexibility 2. Flexible conversion between different levels of modulations formats without O/E/O conversions enable transparent gateways between optical networks and efficient use of fiber spectral resources 3. Reconfigurable bandwidth allocation in flex-grid optical network can improve spectral efficiency by fragmentation and overlapping optical channels. 4. Phase sensitive amplification could be beneficial for in-line optical signal regeneration. Raman assistant further enhances the parametric amplification in a phase-sensitive amplifier.