Medium-density WDM system with Fabry-Perot laser diodes for subscriber loop applications

Abstract

Medium-density wavelength division multiplexing (WDM) systems with approximately four to eight wavelengths can provide an evolution path from near-term fiber-to-the-curb systems to a broadband passive optical network. The authors demonstrate that multilongitudinal-mode Fabry-Perot laser diodes can be used in such a system, with four 622 Mb/s channels in the 1.3- mu m window. This may provide a lower-cost alternative to the use of DFB lasers for such applications. Despite a channel spacing of only 15 nm, significant wavelength misalignments of the laser diodes relative to the WDM passbands can be tolerated before filter-induced mode-partition-noise penalties are observed. The potential for extending the data rate to 1.25 Gb/s is demonstrated.