Numerical research on partially coherent flat-topped beam propagation through atmospheric turbulence along a slant path.

Abstract

In this paper, we investigate the propagation of partially coherent flat-topped (PCFT) beams through atmospheric turbulence along a slant path. Using wave optics simulation (WOS), we calculated the on-axis intensity of PCFT beams in both vacuum and turbulence links, finding that PCFT beams will self-focus during propagation and that the beam coherence length has a significant impact on this focusing phenomenon. The effects of the zenith angle and the source coherence length on the scintillation index and mean signal-to-noise ratio (SNR) are analyzed. Furthermore, taking into consideration the limitation of available devices, we examined the impacts of source coherence time and detector integration time on the performance of PCFT beams in slant links. WOS results indicate as much as an extra 2 dB SNR gain from PCFT beams in short links in comparison with Gaussian Schell-model beams.