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

TL;DR

This paper demonstrates that homodyne detection is a robust and near-optimal method for binary phase-shift keyed optical communication in noisy environments, outperforming traditional receivers at high signal energies.

Contribution

The study provides both theoretical proof and experimental validation that homodyne detection approaches the Helstrom bound under phase diffusion noise, surpassing Kennedy receiver performance.

Findings

Homodyne detection is robust against phase diffusion noise.

Homodyne receiver outperforms Kennedy receiver at high signal energies.

Homodyne detection approaches the Helstrom bound in large noise limit.

Abstract

We address binary optical communication channels based on phase-shift keyed coherent signals in the presence of phase diffusion. We prove theoretically and demonstrate experimentally that a discrimination strategy based on homodyne detection is robust against this kind of noise for any value of the channel energy. Moreover, we find that homodyne receiver beats the performance of Kennedy receiver as the signal energy increases, and achieves the Helstrom bound in the limit of large noise.