Concatenated fiber grating optical monitor

A new optical wavelength-division-multiplexed (WDM) wavelength monitor comprised of concatenated fiber Bragg gratings and an InGaAsP electroabsorption optical modulator is described. Input WDM signals were modulated at 10 kHz with 15-ns-width pulses and the signals reflected from the gratings were detected with an InGaAs p-i-n photodiode and displayed on an oscilloscope as a series of pulses corresponding to each wavelength component.