Design of adaptive optical equalizers for fiber optic communication systems

An efficient optical adaptive equalizer has been developed for the optical processing of guided lightwave signal waveforms corrupted by time-varying dispersion and attenuation effects. The optical equalizer is based upon a tapped delay line filter built by laser ablative chemical etching. The least-mean-square algorithm is used to adapt an equalizer''s weights in real-time as the optical channel varies. The equalizer is designed for incoherent lightwave systems carrying binary, on/off keyed, digital data.