Error probabilities of coherent optical heterodyne OOK signals in a noncoherent detection system degraded by laser phase noise

An error probability analysis is performed for noncoherent detection of optical heterodyne on-off keying (OOK) signals corrupted by laser phase noise and additive white Gaussian noise. An analytic expression for the probability density function of the random variable that models the effect of laser phase noise on system performance is derived based on a high-user-bit-rate assumption. The system performance obtained with the high-bit-rate expression is compared with the system performance obtained with currently used empirically derived expressions. OOK system performance is obtained for different linewidth-to-bit-rate ratios, signal-to-noise ratios, and normalized decision thresholds. The optimum threshold is found to depend on both the signal-to-noise ratio and the linewidth-to-bit-rate ratio