Modulated Grating Y-Structure Tunable Laser for $\lambda$ -Routed Networks and Optical Access

A fast tunable laser based on a modulated grating Y-structure (MG-Y) is demonstrated in direct burst-mode modulation at 2.5 Gb/s. Two transmission scenarios have been evaluated, and a characterization of its wavelength tuning performances in terms of wavelength switching rate and interference has been carried out. The minimum wavelength switching time was found to be 400 ps, and an optical loss budget of 26.7 dB is compatible for the use in optical transmission networks, covering distances up to 50 km while transmitting bursts at alternating wavelengths. Finally, an application in passive optical access networks allowing direct communication between the user terminals without traffic aggregation, and more important, without electrical-optical-electrical conversion or protocol-dependent termination at the premises of the service operator is presented. First results show its feasibility in hybrid wavelength division multiplexing/time division multiplexing networks that give service up to 64 users per tree.