A reconfigurable optoelectronic wavelength converter based on an integrated electroabsorption modulated laser array

Optical wavelength conversion or wavelength adaptation is a desired functionality for evolving WDM network architectures. The ability to perform routing and switching as a function of wavelength in a network can be achieved through wavelength conversion. The one feature necessary for all wavelength converters is the ability to provide a new wavelength which complies with the specified wavelengths in the system. We describe an optoelectronic wavelength converter in which the new wavelength is provided by an integrated electroabsorption modulated laser (EML) array suitable for low-chirp long haul transmission. The converter consists of a photodiode which converts the input optical signal to an electrical signal. This signal is amplified to drive an EA modulator which is integrated with a DFB laser array, passive optical power combiner and optical amplifier. Each laser in the array has a different grating and thus lases at a different wavelength in the 1550 to 1560 nm region. The transmitter can be configured to provide either selected fixed wavelength output or to switch between output wavelengths as determined by network control. We demonstrate the operation of the wavelength converter at 2.5 Gbits/s. The output wavelength is switched between compliant wavelengths spaced by 200 GHz through software control and bit-error-rate (BER) performance is measured.