Tunable carrier signal generation based on spectral shaping using polarization interference

A novel approach to generate frequency and pulse-width adjustable carrier signals using all-fiber components is proposed and demonstrated. The technique is using an all-fiber spectrum shaper which is consisted of a variable differential group delay (DGD) element and a bandwidth-tunable optical filter, to produce required optical power spectrum. Due to the frequency-to-time conversion in a dispersive fiber, the frequency and pulse-width of the obtained carrier signals can be user-defined by modifying the optical spectrum shape. The proposed approach is verified by experiments.