Variable gain equalizer using magneto-optics

The variable gain equalizer proposed operates based on varying the combined spectral shape of two filters. The spectral shape can be changed by a variable optical splitter based on magneto-optics. Experimental results show that spectral shape can be changed using the proposed variable gain equalizer set-up. The spectral tilt varied approximately +/-0.07 dB/nm within a driving current of 0 to 70 mA on the variable optical splitter. Simulation results show possible spectral output using different filter shapes (sinusoidal like). Flexibility in obtaining different spectral shapes can be attained by the proposed variable gain equalizer. The initial filters can be changed to attain an initial output spectrum and the variable optical splitter is used to vary the output spectrum to the desired final shape. Other advantages of this no-moving-parts design are reliability over those that rely on mechanical components and its ability to continuously and rapidly change the output spectrum.