Assessment of the performance of DPSK optical direct detection receivers impaired by in-band crosstalk - analytical formulation validation

In-band crosstalk is a major physical impairment in optical networks. Due to its robustness to in-band crosstalk differential phase-shift keying (DPSK) has surged as an attractive modulation scheme to be used in such environments. In this paper a stochastic simulation based on the Monte Carlo (MC) method that permits to assess the impact of in-band crosstalk on a direct detection DPSK receiver with imperfections is developed. The main objective of the MC simulator is to validate a theoretical work proposed in the literature to assess the performance of direct detection balanced DPSK optical receivers in presence of in-band crosstalk with arbitrary optical and electrical filters. This is accomplished by evaluating the probability density function of the receiver decision variable and the system bit error probability for those receivers.