Optimum-Transmission Free-Space Optical Communications
Optics
2026-04-28 v1 Quantum Physics
Abstract
Slepian developed the Prolate Spheroidal Wavefunction (PSW) spatial-mode basis, which forms the normal modes of the Fresnel-propagation kernel of a free-space optical communications channel bookended by hard-circular apertures. The zero-th order PSW mode has the highest power-transfer eigenvalue, exciting which on the transmitter side therefore maximizes the transmissivity for single-spatial-mode communications. We show that the transmissivity performance of this fundamental PSW mode can be obtained by an aperture-truncated Gaussian beam of an optimized beam waist, despite the two mode shapes deviating from one another in the near-field regime.
Cite
@article{arxiv.2604.23417,
title = {Optimum-Transmission Free-Space Optical Communications},
author = {Prajit Dhara and Babak N. Saif and Jeffrey H. Shapiro and Saikat Guha},
journal= {arXiv preprint arXiv:2604.23417},
year = {2026}
}
Comments
Main paper, plus three Appendices; 17 pages, 10 figures