Time-frequency-varying multicarrier generation using dynamic recirculating frequency shifter

A time-frequency-varying multicarrier generation scheme based on dynamic single-sideband recirculating frequency shifter is proposed and experimentally demonstrated. Through the use of two time-domain sinusoidal signals with stationary phase shift provided by a phase control module, multicarriers with flexible frequency intervals are obtained without carrier-to-noise ratio and flatness loss. We have experimentally attained multicarriers with 10-/12.5-/15-GHz carrier intervals in 3-nm bandwidth, and carriers with arbitrary intervals can be achieved when using the proposed scheme combined with a flexible wavelength selective switch.