Using precoding technique to reduce the BER penalty of an M-QAM channel in hybrid AM-VSB/M-QAM subcarrier multiplexed lightwave systems

We propose and verify through computer simulations the use of a precoding technique to eliminate the nonlinear distortions in an M-QAM channel, which is transported along with multiple AM-VSB channels by a laser diode. We show that the precoding technique can completely remove the clipping-induced bit-error-rate (BER) floor at a cost of a 3-dB signal-to-noise ratio reduction.