arXiv:1305.4201 · Physical Review A
Homodyne detection as a near-optimum receiver for phase-shift-keyed binary communication in the presence of phase diffusion
Stefano Olivares, S. Cialdi, F. Castelli, Matteo G. A. Paris
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 a homodyne receiver beats the performance of a Kennedy receiver as the signal energy increases and achieves the Helstrom bound in the limit of large noise.