Research on performance of convex partially coherent flat-topped beams in vertical atmospheric turbulent paths

Abstract

Previous studies on non-uniformly correlated (NUC) beams mainly focus on beams with Gaussian amplitude profiles. In this paper we research a new class of non-uniformly correlated flat-topped beams, which are called convex partially coherent flat-topped (CPCFT) beams. Using wave optics simulation (WOS), we investigate the propagation properties of such beams in vertical atmospheric turbulent paths in detail and calculated the mean signal-to-noise ratio (SNR) and bit-error rate (BER). It is found that CPCFT beams will self-focus during propagation, resulting in larger on-axis intensity than Gaussian Schell-model (GSM) and PCFT beams, and they also have smaller scintillation in most cases. These properties have made CPCFT beams effective for improving the mean SNR and reducing the mean BER. WOS results show that turbulence induced degradation can be dramatically reduced by using CPCFT beams under certain circumstances.