Primary referenced DWDM frequency comb generator

A practical technique for realising a bank of laser sources for generating a primary-referenced frequency comb in the 1535-1565 nm window is presented. The technique uses a WDM coupler-based wavelength meter that is periodically calibrated to a primary frequency reference. The technique enables the frequency of a laser to be locked to any value within its tunable range and is able to stabilise the frequencies of dense WDM carriers with arbitrary channel spacings. The scheme satisfies the ITU recommendations for optical transmitters for use in DWDM systems