Performance Evaluation of Optical OFDM Systems with Nonlinear Clipping Distortion

This paper investigates the effects of nonlinear biasing and clipping (BAC) on a random optical orthogonal frequency-division multiplexing (OFDM) signal with direct detection. We look at the problem of theoretical performance evaluation of such a system. Specifically, we derive an approximation for the symbol error rate (SER). The nonlinear BAC process is modeled as a linear deterministic gain plus a random additive clipping noise. The total effective SNR is presented as a function of biasing power, modulation constellation and receiver SNR. Analytical results are in good agreement with simulations in various cases.