Simple formula for bit-error rate in optical heterodyne DPSK systems employing polarisation diversity

摘要

A simple bit-error rate (BER) formula for DPSK optical heterodyne systems employing polarisation diversity is presented. It is shown by this formula that the power penalty at BER=10/sup -9/ owing to the polarisation diversity is only 0.4 dB, showing good agreement with previous computer-simulation results. The effect of the laser phase noise can also be considered.