Fast automatic multilevel thresholding method

which was 100% where G,,,= l0dB and G,,,,=20 dB. Therefore, the gain flatness with the hybrid telluritc/silica Raman amplifier was significantly better than with the simde tellurite Raman amdifier. We measured &e bit error rates (BER) in an IM-DD transmission system with the hybrid FRA to conh the applicability of the amplifier to WDM transmission systems. We installed the hybrid FRA as a pre- amplifier downstream of an 80 km standard SMF. Eight signal channels were arranged on the ITU

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