NEW ADVANCES ON OPTICAL-COMPONENTS NEEDED FOR FDM OPTICAL NETWORKS

Two critical components, needed for optical networks based on frequenc y division multiplexing and frequency reuse technologies, are presente d. One is a fast tunable laser, yielding 24 discrete frequencies regul arly spaced by 40 GHz around 1.53 mum. The laser can be switched rando mly in less than 8 ns among these frequencies. Frequency routing of a 3 Gb/s bit stream in 10 ns-packets between 10 different destinations h as been demonstrated with this laser. The second component is a broadb and wavelength shifter capable of switching multigigabit data between optical frequencies in the 1.5-mum region. The device is tunable, casc adable, provides conversion gain and is nearly polarization insensitiv e. Data degradation after wavelength shifting is negligible. Such a de vice provides the means of reusing the limited set of frequencies give n by the lasers and thus of realizing large size networks.