High-Capacity Single-Sideband Suppressed-Carrier Modulation with Integrated Optical Filter in Silicon-on-Insulator Technology

A 5 Gbit/s single-sideband suppressed-carrier (SSB-SC) modulated signal is generated using a phase modulator (PM) and an integrated optical filter implemented with a third-order distributed feedback resonator (DFBR) in a silicon nanowire strip waveguide. Small in-band variations of the integrated filter group delay response have been measured. The moderate impact of the filter phase on the generated SSB-SC signal is also assessed by transmission over 60 km of standard single mode fiber, indicating an additional power penalty of about 1 dB. A frequency shift of 20 GHz for the broadband modulated data is employed in this experimental demonstration. By filtering high-order harmonics from the PM and reinserting the optical carrier, the scheme can be potentially employed for generating SSB-modulated signals up to the mmwave band starting from a lower RF carrier. The proposed architecture is simple and stable, and suitable for realizing a photonic integrated circuit in silicon-on-insulator technology with minimized footprint by monolithic integration of the DFBR filter with the PM.