Homodyne detection as a near-optimum receiver for phase-shift keyed binary communication in the presence of phase diffusion

摘要

We address binary optical communication channels based on phase-shift keyedcoherent signals in the presence of phase diffusion. We prove theoretically anddemonstrate experimentally that a discrimination strategy based on homodynedetection is robust against this kind of noise for any value of the channelenergy. Moreover, we find that homodyne receiver beats the performance ofKennedy receiver as the signal energy increases, and achieves the Helstrombound in the limit of large noise.